Publications

Abstract

Twin studies indicate that dyscalculia (or mathematical disability) is caused partly by a genetic component, which is yet to be understood at the molecular level. Recently, a coding variant (rs133885) in the myosin-18B gene was shown to be associated with mathematical abilities with a specific effect among children with dyslexia. This association represents one of the most significant genetic associations reported to date for mathematical abilities and the only one reaching genome-wide statistical significance.

We conducted a replication study in different cohorts to assess the effect of rs133885 maths-related measures. The study was conducted primarily using the Avon Longitudinal Study of Parents and Children (ALSPAC), (N = 3819). We tested additional cohorts including the York Cohort, the Specific Language Impairment Consortium (SLIC) cohort and the Raine Cohort, and stratified them for a definition of dyslexia whenever possible.

We did not observe any associations between rs133885 in myosin-18B and mathematical abilities among individuals with dyslexia or in the general population. Our results suggest that the myosin-18B variant is unlikely to be a main factor contributing to mathematical abilities.

Abstract

Language production involves the retrieval of information from memory, the planning of an articulatory program, and executive control and self-monitoring. These processes can be related to the domains of long-term memory, motor control, and executive control. Here, we argue that studying neuronal oscillations provides an important opportunity to understand how general neuronal computational principles support language production, also helping elucidate relationships between language and other domains of cognition. For each relevant domain, we provide a brief review of the findings in the literature with respect to neuronal oscillations. Then, we show how similar patterns are found in the domain of language production, both through review of previous literature and novel findings. We conclude that neurophysiological mechanisms, as reflected in modulations of neuronal oscillations, may act as a fundamental basis for bringing together and enriching the fields of language and cognition.

Abstract

Two major components form the basis of spoken word production: the access of conceptual and lexical/phonological information in long-term memory, and motor preparation and execution of an articulatory program. Whereas the motor aspects of word production have been well characterized as reflected in alpha-beta desynchronization, the memory aspects have remained poorly understood. Using magnetoencephalography, we investigated the neurophysiological signature of not only motor but also memory aspects of spoken-word production. Participants named or judged pictures after reading sentences. To probe the involvement of the memory component, we manipulated sentence context. Sentence contexts were either constraining or nonconstraining toward the final word, presented as a picture. In the judgment task, participants indicated with a left-hand button press whether the picture was expected given the sentence. In the naming task, they named the picture. Naming and judgment were faster with constraining than nonconstraining contexts. Alpha-beta desynchronization was found for constraining relative to nonconstraining contexts pre-picture presentation. For the judgment task, beta desynchronization was observed in left posterior brain areas associated with conceptual processing and in right motor cortex. For the naming task, in addition to the same left posterior brain areas, beta desynchronization was found in left anterior and posterior temporal cortex (associated with memory aspects), left inferior frontal cortex, and bilateral ventral premotor cortex (associated with motor aspects). These results suggest that memory and motor components of spoken word production are reflected in overlapping brain oscillations in the beta band.

Abstract

Previous dual-task studies examining the locus of semantic interference of distractor words in picture naming have obtained diverging results. In these studies, participants manually responded to tones and named pictures while ignoring distractor words (picture-word interference, PWI) with varying stimulus onset asynchrony (SOA) between tone and PWI stimulus. Whereas some studies observed no semantic interference at short SOAs, other studies observed effects of similar magnitude at short and long SOAs. The absence of semantic interference in some studies may perhaps be due to better reading skill of participants in these than in the other studies. According to such a reading-ability account, participants' reading skill should be predictive of the magnitude of their interference effect at short SOAs. To test this account, we conducted a dual-task study with tone discrimination and PWI tasks and measured participants' reading ability. The semantic interference effect was of similar magnitude at both short and long SOAs. Participants' reading ability was predictive of their naming speed but not of their semantic interference effect, contrary to the reading ability account. We conclude that the magnitude of semantic interference in picture naming during dual-task performance does not depend on reading skill.

Abstract

Visual stimuli quickly activate a broad network of brain areas that often show reciprocal structural connections between them. Activity at short latencies (<100 ms) is thought to represent a feed-forward activation of widespread cortical areas, but fast activation combined with reciprocal connectivity between areas in principle allows for two-way, recurrent interactions to occur at short latencies after stimulus onset. Here we combined EEG source-imaging and Granger-causal modeling with high temporal resolution to investigate whether recurrent and top-down interactions between visual and attentional brain areas can be identified and distinguished at short latencies in humans. We investigated the directed interactions between widespread occipital, parietal and frontal areas that we localized within participants using fMRI. The connectivity results showed two-way interactions between area MT and V1 already at short latencies. In addition, the results suggested a large role for lateral parietal cortex in coordinating visual activity that may be understood as an ongoing top-down allocation of attentional resources. Our results support the notion that indirect pathways allow early, evoked driving from MT to V1 to highlight spatial locations of motion transients, while influence from parietal areas is continuously exerted around stimulus onset, presumably reflecting task-related attentional processes.

Abstract

To investigate the structure of the bilingual mental lexicon, researchers in the field of bilingualism often use words that exist in multiple languages: cognates (which have the same meaning) and interlingual homographs (which have a different meaning). A high proportion of these studies have investigated language processing in Dutch–English bilinguals. Despite the abundance of research using such materials, few studies exist that have validated such materials. We conducted two rating experiments in which Dutch–English bilinguals rated the meaning, spelling and pronunciation similarity of pairs of Dutch and English words. On the basis of these results, we present a new database of Dutch–English identical cognates (e.g. “wolf”–“wolf”; n = 58), non-identical cognates (e.g. “kat”–“cat”; n = 74), interlingual homographs (e.g. “angel”–“angel”; n = 72) and translation equivalents (e.g. “wortel”–“carrot”; n = 78). The database can be accessed at http://osf.io/tcdxb/.

Abstract

Cognates and interlingual homographs are words that exist in multiple languages. Cognates, like “wolf” in Dutch and English, also carry the same meaning. Interlingual homographs do not: the word “angel” in English refers to a spiritual being, but in Dutch to the sting of a bee. The six experiments included in this thesis examined how these words are represented in the bilingual mental lexicon. Experiment 1 and 2 investigated the issue of task effects on the processing of cognates. Bilinguals often process cognates more quickly than single-language control words (like “carrot”, which exists in English but not Dutch). These experiments showed that the size of this cognate facilitation effect depends on the other types of stimuli included in the task. These task effects were most likely due to response competition, indicating that cognates are subject to processes of facilitation and inhibition both within the lexicon and at the level of decision making. Experiment 3 and 4 examined whether seeing a cognate or interlingual homograph in one’s native language affects subsequent processing in one’s second language. This method was used to determine whether non-identical cognates share a form representation. These experiments were inconclusive: they revealed no effect of cross-lingual long-term priming. Most likely this was because a lexical decision task was used to probe an effect that is largely semantic in nature. Given these caveats to using lexical decision tasks, two final experiments used a semantic relatedness task instead. Both experiments revealed evidence for an interlingual homograph inhibition effect but no cognate facilitation effect. Furthermore, the second experiment found evidence for a small effect of cross-lingual long-term priming. After comparing these findings to the monolingual literature on semantic ambiguity resolution, this thesis concludes that it is necessary to explore the viability of a distributed connectionist account of the bilingual mental lexicon.

Abstract

Background

Current models of how bilinguals process cognates (e.g., “wolf”, which has the same meaning in Dutch and English) and interlingual homographs (e.g., “angel”, meaning “insect’s sting” in Dutch) are based primarily on data from lexical decision tasks. A major drawback of such tasks is that it is difficult—if not impossible—to separate processes that occur during decision making (e.g., response competition) from processes that take place in the lexicon (e.g., lateral inhibition). Instead, we conducted two English semantic relatedness judgement experiments.
Methods

In Experiment 1, highly proficient Dutch–English bilinguals (N = 29) and English monolinguals (N = 30) judged the semantic relatedness of word pairs that included a cognate (e.g., “wolf”–“howl”; n = 50), an interlingual homograph (e.g., “angel”–“heaven”; n = 50) or an English control word (e.g., “carrot”–“vegetable”; n = 50). In Experiment 2, another group of highly proficient Dutch–English bilinguals (N = 101) read sentences in Dutch that contained one of those cognates, interlingual homographs or the Dutch translation of one of the English control words (e.g., “wortel” for “carrot”) approximately 15 minutes prior to completing the English semantic relatedness task.
Results

In Experiment 1, there was an interlingual homograph inhibition effect of 39 ms only for the bilinguals, but no evidence for a cognate facilitation effect. Experiment 2 replicated these findings and also revealed that cross-lingual long-term priming had an opposite effect on the cognates and interlingual homographs: recent experience with a cognate in Dutch speeded processing of those items 15 minutes later in English but slowed processing of interlingual homographs. However, these priming effects were smaller than previously observed using a lexical decision task.
Conclusion

After comparing our results to studies in both the bilingual and monolingual domain, we argue that bilinguals appear to process cognates and interlingual homographs as monolinguals process polysemes and homonyms, respectively. In the monolingual domain, processing of such words is best modelled using distributed connectionist frameworks. We conclude that it is necessary to explore the viability of such a model for the bilingual case.

Abstract

Objective

Resting-state functional magnetic resonance imaging (fMRI) is promising for Alzheimer’s disease (AD). This study aimed to examine short-term reliability of the default-mode network (DMN), one of the main haemodynamic patterns of the brain.
Materials and methods

Using a 1.5 T Philips Achieva scanner, two consecutive resting-state fMRI runs were acquired on 69 healthy adults, 62 patients with mild cognitive impairment (MCI) due to AD, and 28 patients with AD dementia. The anterior and posterior DMN and, as control, the visual-processing network (VPN) were computed using two different methodologies: connectivity of predetermined seeds (theory-driven) and dual regression (data-driven). Divergence and convergence in network strength and topography were calculated with paired t tests, global correlation coefficients, voxel-based correlation maps, and indices of reliability.
Results

No topographical differences were found in any of the networks. High correlations and reliability were found in the posterior DMN of healthy adults and MCI patients. Lower reliability was found in the anterior DMN and in the VPN, and in the posterior DMN of dementia patients.
Discussion

Strength and topography of the posterior DMN appear relatively stable and reliable over a short-term period of acquisition but with some degree of variability across clinical samples.

Abstract

Peer behaviour plays an important role in the development of social adjustment, though little is known about its genetic architecture. We conducted a twin study combined with a genome-wide complex trait analysis (GCTA) and a genome-wide screen to characterise genetic influences on problematic peer behaviour during childhood and adolescence. This included a series of longitudinal measures (parent-reported Strengths-and-Difficulties Questionnaire) from a UK population-based birth-cohort (ALSPAC, 4–17 years), and a UK twin sample (TEDS, 4–11 years). Longitudinal twin analysis (TEDS; N ≤ 7,366 twin pairs) showed that peer problems in childhood are heritable (4–11 years, 0.60 < twin-h 2 ≤ 0.71) but genetically heterogeneous from age to age (4–11 years, twin-r g = 0.30). GCTA (ALSPAC: N ≤ 5,608, TEDS: N ≤ 2,691) provided furthermore little support for the contribution of measured common genetic variants during childhood (4–12 years, 0.02 < GCTA-h 2(Meta) ≤ 0.11) though these influences become stronger in adolescence (13–17 years, 0.14 < GCTA-h 2(ALSPAC) ≤ 0.27). A subsequent cross-sectional genome-wide screen in ALSPAC (N ≤ 6,000) focussed on peer problems with the highest GCTA-heritability (10, 13 and 17 years, 0.0002 < GCTA-P ≤ 0.03). Single variant signals (P ≤ 10−5) were followed up in TEDS (N ≤ 2835, 9 and 11 years) and, in search for autism quantitative trait loci, explored within two autism samples (AGRE: N Pedigrees = 793; ACC: N Cases = 1,453/N Controls = 7,070). There was, however, no evidence for association in TEDS and little evidence for an overlap with the autistic continuum. In summary, our findings suggest that problematic peer relationships are heritable but genetically complex and heterogeneous from age to age, with an increase in common measurable genetic variation during adolescence.

Abstract

Gesture–speech synchrony re-stabilizes when hand movement or speech is disrupted by a delayed
feedback manipulation, suggesting strong bidirectional coupling between gesture and speech. Yet it
has also been argued from case studies in perceptual–motor pathology that hand gestures are a special
kind of action that does not require closed-loop re-afferent feedback to maintain synchrony with
speech. In the current pre-registered within-subject study, we used motion tracking to conceptually
replicate McNeill’s (1992) classic study on gesture–speech synchrony under normal and 150 ms
delayed auditory feedback of speech conditions (NO DAF vs. DAF). Consistent with, and extending
McNeill’s original results, we obtain evidence that (a) gesture-speech synchrony is more stable
under DAF versus NO DAF (i.e., increased coupling effect), (b) that gesture and speech variably
entrain to the external auditory delay as indicated by a consistent shift in gesture-speech synchrony
offsets (i.e., entrainment effect), and (c) that the coupling effect and the entrainment effect are codependent.
We suggest, therefore, that gesture–speech synchrony provides a way for the cognitive
system to stabilize rhythmic activity under interfering conditions.

Abstract

Spontaneously occurring speech is often seamlessly accompanied by hand gestures. Detailed
observations of video data suggest that speech and gesture are tightly synchronized in time,
consistent with a dynamic interplay between body and mind. However, spontaneous gesturespeech
synchrony has rarely been objectively quantified beyond analyses of video data, which
do not allow for identification of kinematic properties of gestures. Consequently, the point in
gesture which is held to couple with speech, the so-called moment of “maximum effort”, has
been variably equated with the peak velocity, peak acceleration, peak deceleration, or the onset
of the gesture. In the current exploratory report, we provide novel evidence from motiontracking
and acoustic data that peak velocity is closely aligned, and shortly leads, the peak pitch
(F0) of speech

Abstract

The split-attention effect entails that learning from spatially separated, but mutually referring information
sources (e.g., text and picture), is less effective than learning from the equivalent spatially integrated
sources. According to cognitive load theory, impaired learning is caused by the working memory load
imposed by the need to distribute attention between the information sources and mentally integrate them.
In this study, we directly tested whether the split-attention effect is caused by spatial separation per se.
Spatial distance was varied in basic cognitive tasks involving pictures (Experiment 1) and text–picture
combinations (Experiment 2; preregistered study), and in more ecologically valid learning materials
(Experiment 3). Experiment 1 showed that having to integrate two pictorial stimuli at greater distances
diminished performance on a secondary visual working memory task, but did not lead to slower
integration. When participants had to integrate a picture and written text in Experiment 2, a greater
distance led to slower integration of the stimuli, but not to diminished performance on the secondary task.
Experiment 3 showed that presenting spatially separated (compared with integrated) textual and pictorial
information yielded fewer integrative eye movements, but this was not further exacerbated when
increasing spatial distance even further. This effect on learning processes did not lead to differences in
learning outcomes between conditions. In conclusion, we provide evidence that larger distances between
spatially separated information sources influence learning processes, but that spatial separation on its
own is not likely to be the only, nor a sufficient, condition for impacting learning outcomes.

Abstract

This article aims to explore the scope of a Situated and Embodied Social Psychology (ESP). At first sight, social cognition seems embodied cognition par excellence. Social cognition is first and foremost a supra-individual, interactive, and dynamic process (Semin & Smith, 2013). Radical approaches in Situated/Embodied Cognitive Science (Enactivism) claim that social cognition consists in an emergent pattern of interaction between a continuously coupled organism and the (social) environment; it rejects representationalist accounts of cognition (Hutto & Myin, 2013). However, mainstream ESP (Barsalou, 1999, 2008) still takes a rather representation-friendly approach that construes embodiment in terms of specific bodily formatted representations used (activated) in social cognition. We argue that mainstream ESP suffers from vestiges of theoretical solipsism, which may be resolved by going beyond internalistic spirit that haunts mainstream ESP today.

Abstract

The present study investigated whether speech-related spectral information benefits from initially predominant right or left hemisphere processing. Normal hearing individuals categorized speech sounds composed of an ambiguous base (perceptually intermediate between /ga/ and /da/), presented to one ear, and a disambiguating low or high F3 chirp presented to the other ear. Shorter response times were found when the chirp was presented to the left ear than to the right ear (inducing initially right-hemisphere chirp processing), but no between-ear differences in strength of overall integration. The results are in line with the assumptions of a right hemispheric dominance for spectral processing.

Abstract

The field of psycholinguistics is currently experiencing an explosion of interest in the analysis of neural oscillations—rhythmic brain activity synchronized at different temporal and spatial levels. Given that language comprehension relies on a myriad of processes, which are carried out in parallel in distributed brain networks, there is hope that this methodology might bring the field closer to understanding some of the more basic (spatially and temporally distributed, yet at the same time often overlapping) neural computations that support language function. In this review, we discuss existing proposals linking oscillatory dynamics in different frequency bands to basic neural computations and review relevant theories suggesting associations between band-specific oscillations and higher-level cognitive processes. More or less consistent patterns of oscillatory activity related to certain types of linguistic processing can already be derived from the evidence that has accumulated over the past few decades. The centerpiece of the current review is a synthesis of such patterns grouped by linguistic phenomenon. We restrict our review to evidence linking measures of oscillatory
power to the comprehension of sentences, as well as linguistically (and/or pragmatically) more complex structures. For each grouping, we provide a brief summary and a table of associated oscillatory signatures that a psycholinguist might expect to find when employing a particular linguistic task. Summarizing across different paradigms, we conclude that a handful of basic neural oscillatory mechanisms are likely recruited in different ways and at different times for carrying out a variety of linguistic computations.

Abstract

Symbolic play has long been considered a fertile context for communicative development (Bruner, 1983, Child's talk: Learning to use language, Oxford University Press, Oxford; Vygotsky, 1962, Thought and language, MIT Press, Cambridge, MA; Vygotsky, 1978, Mind in society: The development of higher psychological processes. Harvard University Press, Cambridge, MA). In the current study, we examined caregiver–infant interaction during symbolic play and compared it to interaction in a comparable but non‐symbolic context (i.e., ‘functional’ play). Fifty‐four (N = 54) caregivers and their 18‐month‐old infants were observed engaging in 20 min of play (symbolic, functional). Play interactions were coded and compared across play conditions for joint attention (JA) and gesture use. Compared with functional play, symbolic play was characterized by greater frequency and duration of JA and greater gesture use, particularly the use of iconic gestures with an object in hand. The results suggest that symbolic play provides a rich context for the exchange and negotiation of meaning, and thus may contribute to the development of important skills underlying communicative development.

Abstract

Phosphoglucomutase 1 (PGM1) encodes the metabolic enzyme that interconverts glucose-6-P and glucose-1-P. Mutations in PGM1 cause impairment in glycogen metabolism and glycosylation, the latter manifesting as a congenital disorder of glycosylation (CDG). This unique metabolic defect leads to abnormal N-glycan synthesis in the endoplasmic reticulum (ER) and the Golgi apparatus (GA). On the basis of the decreased galactosylation in glycan chains, galactose was administered to individuals with PGM1-CDG and was shown to markedly reverse most disease-related laboratory abnormalities. The disease and treatment mechanisms, however, have remained largely elusive. Here, we confirm the clinical benefit of galactose supplementation in PGM1-CDG-affected individuals and obtain significant insights into the functional and biochemical regulation of glycosylation. We report here that, by using tracer-based metabolomics, we found that galactose treatment of PGM1-CDG fibroblasts metabolically re-wires their sugar metabolism, and as such replenishes the depleted levels of galactose-1-P, as well as the levels of UDP-glucose and UDP-galactose, the nucleotide sugars that are required for ER- and GA-linked glycosylation, respectively. To this end, we further show that the galactose in UDP-galactose is incorporated into mature, de novo glycans. Our results also allude to the potential of monosaccharide therapy for several other CDG.

Abstract

Automatic word count estimation (WCE) from audio recordings can be used to quantify the amount of verbal communication in a recording environment. One key application of WCE is to measure language input heard by infants and toddlers in their natural environments, as captured by daylong recordings from microphones worn by the infants. Although WCE is nearly trivial for high-quality signals in high-resource languages, daylong recordings are substantially more challenging due to the unconstrained acoustic environments and the presence of near- and far-field speech. Moreover, many use cases of interest involve languages for which reliable ASR systems or even well-defined lexicons are not available. A good WCE system should also perform similarly for low- and high-resource languages in order to enable unbiased comparisons across different cultures and environments. Unfortunately, the current state-of-the-art solution, the LENA system, is based on proprietary software and has only been optimized for American English, limiting its applicability. In this paper, we build on existing work on WCE and present the steps we have taken towards a freely available system for WCE that can be adapted to different languages or dialects with a limited amount of orthographically transcribed speech data. Our system is based on language-independent syllabification of speech, followed by a language-dependent mapping from syllable counts (and a number of other acoustic features) to the corresponding word count estimates. We evaluate our system on samples from daylong infant recordings from six different corpora consisting of several languages and socioeconomic environments, all manually annotated with the same protocol to allow direct comparison. We compare a number of alternative techniques for the two key components in our system: speech activity detection and automatic syllabification of speech. As a result, we show that our system can reach relatively consistent WCE accuracy across multiple corpora and languages (with some limitations). In addition, the system outperforms LENA on three of the four corpora consisting of different varieties of English. We also demonstrate how an automatic neural network-based syllabifier, when trained on multiple languages, generalizes well to novel languages beyond the training data, outperforming two previously proposed unsupervised syllabifiers as a feature extractor for WCE.

Abstract

In response to: How to learn about teaching: An evolutionary framework for the study of teaching behavior in humans and other animals

Arguments about the nature of teaching have depended principally on naturalistic observation and some experimental work. Additional measurement tools, and physiological variations and manipulations can provide insights on the intrinsic structure and state of the participants better than verbal descriptions alone: namely, time-series analysis, and examination of the role of hormones and neuromodulators on the behaviors of teacher and pupil.

Abstract

Time is one crucial dimension conveying information in animal communication. Evolution has shaped animals’ nervous systems to produce signals with temporal properties fitting their socio-ecological niches. Many quantitative models of mechanisms underlying rhythmic behaviour exist, spanning insects, crustaceans, birds, amphibians, and mammals. However, these computational and mathematical models are often presented in isolation. Here, we provide an overview of the main mathematical models employed in the study of animal rhythmic communication among conspecifics. After presenting basic definitions and mathematical formalisms, we discuss each individual model. These computational models are then compared using simulated data to uncover similarities and key differences in the underlying mechanisms found across species. Our review of the empirical literature is admittedly limited. We stress the need of using comparative computer simulations – both before and after animal experiments – to better understand animal timing in interaction. We hope this article will serve as a potential first step towards a common computational framework to describe temporal interactions in animals, including humans.

Abstract

Comparative pattern learning experiments investigate how different species find regularities in sensory input, providing insights into cognitive processing in humans and other animals. Past research has focused either on one species’ ability to process pattern classes or different species’ performance in recognizing the same pattern, with little attention to individual and species-specific heuristics and decision strategies. We trained and tested two bird species, pigeons (Columba livia) and kea (Nestor notabilis, a parrot species), on visual patterns using touch-screen technology. Patterns were composed of several abstract elements and had varying degrees of structural complexity. We developed a model selection paradigm, based on regular expressions, that allowed us to reconstruct the specific decision strategies and cognitive heuristics adopted by a given individual in our task. Individual birds showed considerable differences in the number, type and heterogeneity of heuristic strategies adopted. Birds’ choices also exhibited consistent species-level differences. Kea adopted effective heuristic strategies, based on matching learned bigrams to stimulus edges. Individual pigeons, in contrast, adopted an idiosyncratic mix of strategies that included local transition probabilities and global string similarity. Although performance was above chance and quite high for kea, no individual of either species provided clear evidence of learning exactly the rule used to generate the training stimuli. Our results show that similar behavioral outcomes can be achieved using dramatically different strategies and highlight the dangers of combining multiple individuals in a group analysis. These findings, and our general approach, have implications for the design of future pattern learning experiments, and the interpretation of comparative cognition research more generally.

Abstract

The study of human language is progressively moving toward comparative and interactive frameworks, extending the concept of turn‐taking to animal communication. While such an endeavor will help us understand the interactive origins of language, any theoretical account for cross‐species turn‐taking should consider three key points. First, animal turn‐taking must incorporate biological studies on animal chorusing, namely how different species coordinate their signals over time. Second, while concepts employed in human communication and turn‐taking, such as intentionality, are still debated in animal behavior, lower level mechanisms with clear neurobiological bases can explain much of animal interactive behavior. Third, social behavior, interactivity, and cooperation can be orthogonal, and the alternation of animal signals need not be cooperative. Considering turn‐taking a subset of chorusing in the rhythmic dimension may avoid overinterpretation and enhance the comparability of future empirical work.

Abstract

Puppyhood is a very active social and vocal period in a harbor seal's life Phoca vitulina. An important feature of vocalizations is their temporal and rhythmic structure, and understanding vocal timing and rhythms in harbor seals is critical to a cross-species hypothesis in evolutionary neuroscience that links vocal learning, rhythm perception, and synchronization. This study utilized analytical techniques that may best capture rhythmic structure in pup vocalizations with the goal of examining whether (1) harbor seal pups show rhythmic structure in their calls and (2) rhythms evolve over time. Calls of 3 wild-born seal pups were recorded daily over the course of 1-3 weeks; 3 temporal features were analyzed using 3 complementary techniques. We identified temporal and rhythmic structure in pup calls across different time windows. The calls of harbor seal pups exhibit some degree of temporal and rhythmic organization, which evolves over puppyhood and resembles that of other species' interactive communication. We suggest next steps for investigating call structure in harbor seal pups and propose comparative hypotheses to test in other pinniped species.

Abstract

Comparative research investigating how nonhuman animals generalize patterns of auditory stimuli often uses sequences of human speech syllables and reports limited generalization abilities in animals. Here, we reverse this logic, testing humans with stimulus sequences tailored to squirrel monkeys. When test stimuli are familiar (human voices), humans succeed in two types of generalization. However, when the same structural rule is instantiated over unfamiliar but perceivable sounds within squirrel monkeys’ optimal hearing frequency range, human participants master only one type of generalization. These findings have methodological implications for the design of comparative experiments, which should be fair towards all tested species’ proclivities and limitations.

Abstract

Animal communication and motoric behavior develop over time. Often, this temporal dimension has communicative relevance and is organized according to structural patterns. In other words, time is a crucial dimension for rhythm and synchrony in animal movement and communication. Rhythm is defined as temporal structure at a second-millisecond time scale (Kotz et al. 2018). Synchrony is defined as precise co-occurrence of 2 behaviors in time (Ravignani 2017).

Rhythm, synchrony, and other forms of temporal interaction are taking center stage in animal behavior and communication. Several critical questions include, among others: what species show which rhythmic predispositions? How does a species’ sensitivity for, or proclivity towards, rhythm arise? What are the species-specific functions of rhythm and synchrony, and are there functional trends across species? How did similar or different rhythmic behaviors evolved in different species? This Special Column aims at collecting and contrasting research from different species, perceptual modalities, and empirical methods. The focus is on timing, rhythm and synchrony in the second-millisecond range.

Three main approaches are commonly adopted to study animal rhythms, with a focus on: 1) spontaneous individual rhythm production, 2) group rhythms, or 3) synchronization experiments. I concisely introduce them below (see also Kotz et al. 2018; Ravignani et al. 2018).

Abstract

Why does human speech have rhythm? As we cannot travel back in time to witness how speech developed its rhythmic properties and why humans have the cognitive skills to process them, we rely on alternative methods to find out. One powerful tool is the comparative approach: studying the presence or absence of cognitive/behavioral traits in other species to determine which traits are shared between species and which are recent human inventions. Vocalizations of many species exhibit temporal structure, but little is known about how these rhythmic structures evolved, are perceived and produced, their biological and developmental bases, and communicative functions. We review the literature on rhythm in speech and animal vocalizations as a first step toward understanding similarities and differences across species. We extend this review to quantitative techniques that are useful for computing rhythmic structure in acoustic sequences and hence facilitate cross‐species research. We report links between vocal perception and motor coordination and the differentiation of rhythm based on hierarchical temporal structure. While still far from a complete cross‐species perspective of speech rhythm, our review puts some pieces of the puzzle together.

Abstract

Alternative mathematical models predict differences in how animals adjust the timing of their calls. Differences can be measured as the effect of the timing of a conspecific call on the rate and period of calling of a focal animal, and the lag between the two. Here, I test these alternative hypotheses by tapping into harbor seals’ (Phoca vitulina) mechanisms for spontaneous timing. Both socioecology and vocal behavior of harbor seals make them an interesting model species to study call rhythm and timing. Here, a wild-born seal pup was tested in controlled laboratory conditions. Based on previous recordings of her vocalizations and those of others, I designed playback experiments adapted to that specific animal. The call onsets of the animal were measured as a function of tempo, rhythmic regularity, and spectral properties of the playbacks. The pup adapted the timing of her calls in response to conspecifics’ calls. Rather than responding at a fixed time delay, the pup adjusted her calls’ onset to occur at a fraction of the playback tempo, showing a relative-phase antisynchrony. Experimental results were confirmed via computational modeling. This case study lends preliminary support to a classic mathematical model of animal behavior—Hamilton’s selfish herd—in the acoustic domain.

Abstract

Understanding worldwide patterns of language diversity has long been a goal for evolutionary scientists, linguists and philosophers. Research over the past decade has suggested that linguistic diversity may result from differences in the social environments in which languages evolve. Specifically, recent work found that languages spoken in larger communities typically have more systematic grammatical structures. However, in the real world, community size is confounded with other social factors such as network structure and the number of second languages learners in the community, and it is often assumed that linguistic simplification is driven by these factors instead. Here, we show that in contrast to previous assumptions, community size has a unique and important influence on linguistic structure. We experimentally examine the live formation of new languages created in the laboratory by small and larger groups, and find that larger groups of interacting participants develop more systematic languages over time, and do so faster and more consistently than small groups. Small groups also vary more in their linguistic behaviours, suggesting that small communities are more vulnerable to drift. These results show that community size predicts patterns of language diversity, and suggest that an increase in community size might have contributed to language evolution.

Abstract

Experimental work in the field of language evolution has shown that novel signal systems become more structured over time. In a recent paper, Kirby, Tamariz, Cornish, and Smith (2015) argued that compositional languages can emerge only when languages are transmitted across multiple generations. In the current paper, we show that compositional languages can emerge in a closed community within a single generation. We conducted a communication experiment in which we tested the emergence of linguistic structure in different micro-societies of four participants, who interacted in alternating dyads using an artificial language to refer to novel meanings. Importantly, the communication included two real-world aspects of language acquisition and use, which introduce compressibility pressures: (a) multiple interaction partners and (b) an expanding meaning space. Our results show that languages become significantly more structured over time, with participants converging on shared, stable, and compositional lexicons. These findings indicate that new learners are not necessary for the formation of linguistic structure within a community, and have implications for related fields such as developing sign languages and creoles.

Abstract

Recognizing that two elements within a sequence of variable length depend on each other is a key ability in understanding the structure of language and music. Perception of such interdependencies has previously been documented in chimpanzees in the visual domain and in human infants and common squirrel monkeys with auditory playback experiments, but it remains unclear whether it typifies primates in general. Here, we investigated the ability of common marmosets (Callithrix jacchus) to recognize and respond to such dependencies. We tested subjects in a familiarization-discrimination playback experiment using stimuli composed of pure tones that either conformed or did not conform to a grammatical rule. After familiarization to sequences with dependencies, marmosets spontaneously discriminated between sequences containing and lacking dependencies (‘consistent’ and ‘inconsistent’, respectively), independent of stimulus length. Marmosets looked more often to the sound source when hearing sequences consistent with the familiarization stimuli, as previously found in human infants. Crucially, looks were coded automatically by computer software, avoiding human bias. Our results support the hypothesis that the ability to perceive dependencies at variable distances was already present in the common ancestor of all anthropoid primates (Simiiformes).

Abstract

In our interactions with people and objects in the world around us, as well as in communicating our thoughts, we
rely on the use of conceptual knowledge stored in long-term memory. From a frame-theoretic point of view, a
concept is represented by a central node and recursive attribute-value structures further specifying the concept.
The present study explores whether and how the activation of an attribute within a frame might influence access
to the concept's name in language production, focussing on the colour attribute. Colour has been shown to
contribute to object recognition, naming, and memory retrieval, and there is evidence that colour plays a different
role in naming objects that have a typical colour (high colour-diagnostic objects such as tomatoes) than in
naming objects without a typical colour (low colour-diagnostic objects such as bicycles). We report two behavioural
experiments designed to reveal potential effects of the activation of an object's typical colour on naming
the object in a picture-word interference paradigm. This paradigm was used to investigate whether naming is
facilitated when typical colours are presented alongside the to-be-named picture (e.g., the word “red” superimposed
on the picture of a tomato), compared to atypical colours (such as “brown”), unrelated adjectives (such
as “fast”), or random letter strings. To further explore the time course of these potential effects, the words were
presented at different time points relative to the to-be-named picture (Exp. 1: −400 ms, Exp. 2: −200 ms, 0 ms,
and+200 ms). By including both high and low colour-diagnostic objects, it was possible to explore whether the
activation of a colour differentially affects naming of objects that have a strong association with a typical colour.
The results showed that (pre-)activation of the appropriate colour attribute facilitated naming compared to an
inappropriate colour. This was only the case for objects closely connected with a typical colour. Consequences of
these findings for frame-theoretic accounts of conceptual representation are discussed.

Abstract

The present study used event-related potentials to investigate whether the processing of grammatical gender agreement involving gender regular and irregular forms recruit the same or distinct neurocognitive mechanisms and whether different grammatical gender agreement conditions elicit the same or diverse ERP signals. Native speakers of Brazilian Portuguese read sentences containing congruent and incongruent grammatical gender agreement between a determiner and a regular or an irregular form (condition 1) and between a regular or an irregular form and an adjective (condition 2). However, in condition 2, trials with incongruent regular forms elicited more positive ongoing waveforms than trial with incongruent irregular forms. We found a biphasic LAN/P600 effect for gender agreement violation involving regular and irregular forms in both conditions. Our findings suggest that gender agreement between determiner and nouns recruits the same neurocognitive mechanisms regardless of the nouns’ form and that, depending on the grammatical class of the words involved in gender agreement, differences in ERP signals can emerge

Abstract

Thematic roles such as Agent and Instrument have a long-standing place in theories of event representation. Nonetheless, the structure of these categories has been difficult to determine. We investigated how instrumental events, such as someone slicing bread with a knife, are categorized in English. Speakers described a variety of typical and atypical instrumental events, and we determined the similarity structure of their descriptions using correspondence analysis. We found that events where the instrument is an extension of an intentional agent were most likely to elicit similar language, highlighting the importance of agency in structuring instrumental categories.

Abstract

The status of thematic roles such as Agent and Patient in cognitive science is highly controversial: To some they are universal components of core knowledge, to others they are scholarly fictions without psychological reality. We address this debate by posing two critical questions: to what extent do humans represent events in terms of abstract role categories, and to what extent are these categories shaped by universal cognitive biases? We review a range of literature that contributes answers to these questions: psycholinguistic and event cognition experiments with adults, children, and infants; typological studies grounded in cross-linguistic data; and studies of emerging sign languages. We pose these questions for a variety of roles and find that the answers depend on the role. For Agents and Patients, there is strong evidence for abstract role categories and a universal bias to distinguish the two roles. For Goals and Recipients, we find clear evidence for abstraction but mixed evidence as to whether there is a bias to encode Goals and Recipients as part of one or two distinct categories. Finally, we discuss the Instrumental role and do not find clear evidence for either abstraction or universal biases to structure instrumental categories.

Abstract

Cadherin-13 (CDH13), a unique glycosylphosphatidylinositol-anchored member of the cadherin family of cell adhesion molecules, has been identified as a risk gene for attention-deficit/hyperactivity disorder (ADHD) and various comorbid neurodevelopmental and psychiatric conditions, including depression, substance abuse, autism spectrum disorder and violent behavior, while the mechanism whereby CDH13 dysfunction influences pathogenesis of neuropsychiatric disorders remains elusive. Here we explored the potential role of CDH13 in the inhibitory modulation of brain activity by investigating synaptic function of GABAergic interneurons. Cellular and subcellular distribution of CDH13 was analyzed in the murine hippocampus and a mouse model with a targeted inactivation of Cdh13 was generated to evaluate how CDH13 modulates synaptic activity of hippocampal interneurons and behavioral domains related to psychopathologic (endo)phenotypes. We show that CDH13 expression in the cornu ammonis (CA) region of the hippocampus is confined to distinct classes of interneurons. Specifically, CDH13 is expressed by numerous parvalbumin and somatostatin-expressing interneurons located in the stratum oriens, where it localizes to both the soma and the presynaptic compartment. Cdh13−/− mice show an increase in basal inhibitory, but not excitatory, synaptic transmission in CA1 pyramidal neurons. Associated with these alterations in hippocampal function, Cdh13−/− mice display deficits in learning and memory. Taken together, our results indicate that CDH13 is a negative regulator of inhibitory synapses in the hippocampus, and provide insights into how CDH13 dysfunction may contribute to the excitatory/inhibitory imbalance observed in neurodevelopmental disorders, such as ADHD and autism.

Abstract

Talhelm et al. (2014) test the hypothesis that activities which require more intensive collaboration foster more collectivist cultures. They demonstrate that a measure of collectivism correlates with the proportion of cultivated land devoted to rice paddies, which require more work to grow and maintain than other grains. The data come from individual measures of provinces in China. While the data is analyzed carefully, one aspect that is not directly controlled for is the historical relations between these provinces. Spurious correlations can occur between cultural traits that are inherited from ancestor cultures or borrowed through contact, what is commonly known as Galton's problem (Roberts and Winters, 2013). Effectively, Talhelm et al. treat the measures of each province as independent samples, while in reality both farming practices (e.g., Renfrew, 1997; Diamond and Bellwood, 2003; Lee and Hasegawa, 2011) and cultural values (e.g., Currie et al., 2010; Bulbulia et al., 2013) can be inherited or borrowed. This means that the data may be composed of non-independent points, inflating the apparent correlation between rice growing and collectivism. The correlation between farming practices and collectivism may be robust, but this cannot be known without an empirical control for the relatedness of the samples. Talhelm et al. do discuss this problem in the supplementary materials of their paper. They acknowledge that a phylogenetic analysis could be used to control for relatedness, but that at the time of publication there were no genetic or linguistic trees of descent which are detailed enough to suit this purpose. In this commentary I would like to make two points. First, since the original publication, researchers have created new linguistic trees that can provide the needed resolution. For example, the Glottolog phylogeny (Hammarström et al., 2015) has at least three levels of classification for the relevant varieties, though this does not have branch lengths (see also “reference” trees produced in List et al., 2014). Another recently published phylogeny uses lexical data to construct a phylogenetic tree for many language varieties within China (List et al., 2014). In this commentary I use these lexical data to estimate cultural contact between different provinces, and test whether these measures explain variation in rice farming pracices. However, the second point is that Talhelm et al. focus on descent (vertical transmission), while it may be relevant to control for both descent and borrowing (horizontal transmission). In this case, all that is needed is some measure of cultural contact between groups, not necessarily a unified tree of descent. I use a second source of linguistic data to calculate simple distances between languages based directly on the lexicon. These distances reflect borrowing as well as descent.

Abstract

A previous study by Chen demonstrates a correlation between languages that grammatically mark future events and their speakers' propensity to save, even after controlling for numerous economic and demographic factors. The implication is that languages which grammatically distinguish the present and the future may bias their speakers to distinguish them psychologically, leading to less future-oriented decision making. However, Chen's original analysis assumed languages are independent. This neglects the fact that languages are related, causing correlations to appear stronger than is warranted (Galton's problem). In this paper, we test the robustness of Chen's correlations to corrections for the geographic and historical relatedness of languages. While the question seems simple, the answer is complex. In general, the statistical correlation between the two variables is weaker when controlling for relatedness. When applying the strictest tests for relatedness, and when data is not aggregated across individuals, the correlation is not significant. However, the correlation did remain reasonably robust under a number of tests. We argue that any claims of synchronic patterns between cultural variables should be tested for spurious correlations, with the kinds of approaches used in this paper. However, experiments or case-studies would be more fruitful avenues for future research on this specific topic, rather than further large-scale cross-cultural correlational studies.

Abstract

We suggest that it is now possible to conduct research on a topic which might be called evolutionary geophonetics. The main question is how the climate influences the evolution of language. This involves biological adaptations to the climate that may affect biases in production and perception; cultural evolutionary adaptations of the sounds of a language to climatic conditions; and influences of the climate on language diversity and contact. We discuss these ideas with special reference to a recent hypothesis that lexical tone is not adaptive in dry climates (Everett, Blasi & Roberts, 2015).

Abstract

The timing of turn taking in conversation is extremely rapid given the cognitive demands on speakers to comprehend, plan and execute turns in real time. Findings from psycholinguistics predict that the timing of turn taking is influenced by demands on processing, such as word frequency or syntactic complexity. An alternative view comes from the field of conversation analysis, which predicts that the rules of turn-taking and sequence organization may dictate the variation in gap durations (e.g. the functional role of each turn in communication). In this paper, we estimate the role of these two different kinds of factors in determining the speed of turn-taking in conversation. We use the Switchboard corpus of English telephone conversation, already richly annotated for syntactic structure speech act sequences, and segmental alignment. To this we add further information including Floor Transfer Offset (the amount of time between the end of one turn and the beginning of the next), word frequency, concreteness, and surprisal values. We then apply a novel statistical framework ('random forests') to show that these two dimensions are interwoven together with indexical properties of the speakers as explanatory factors determining the speed of response. We conclude that an explanation of the of the timing of turn taking will require insights from both processing and sequence organisation.

Abstract

Many psycholinguistic models of speech sequence planning make claims about the onset and offset times of planning units, such as words, syllables, and phonemes. These predictions typically go untested, however, since psycholinguists have assumed that the temporal dynamics of the speech signal is a poor index of the temporal dynamics of the underlying speech planning process. This article argues that this problem is tractable, and presents and validates two simple metrics that derive planning unit onset and offset times from the acoustic signal and articulatographic data.

Abstract

Background Bats are able to employ an astonishingly complex vocal repertoire for navigating their environment and conveying social information. A handful of species also show evidence for vocal learning, an extremely rare ability shared only with humans and few other animals. However, despite their potential for the study of vocal communication, bats remain severely understudied at a molecular level. To address this fundamental gap we performed the first transcriptome profiling and genetic interrogation of molecular networks in the brain of a highly vocal bat species, Phyllostomus discolor. Results Gene network analysis typically needs large sample sizes for correct clustering, this can be prohibitive where samples are limited, such as in this study. To overcome this, we developed a novel bioinformatics methodology for identifying robust co-expression gene networks using few samples (N=6). Using this approach, we identified tissue-specific functional gene networks from the bat PAG, a brain region fundamental for mammalian vocalisation. The most highly connected network identified represented a cluster of genes involved in glutamatergic synaptic transmission. Glutamatergic receptors play a significant role in vocalisation from the PAG, suggesting that this gene network may be mechanistically important for vocal-motor control in mammals. Conclusion We have developed an innovative approach to cluster co-expressing gene networks and show that it is highly effective in detecting robust functional gene networks with limited sample sizes. Moreover, this work represents the first gene network analysis performed in a bat brain and establishes bats as a novel, tractable model system for understanding the genetics of vocal mammalian communication.

Abstract

The origins of the Mayna language, formerly spoken in northwest Peruvian Amazonia, remain a mystery for most scholars. Several discussions on it took place in the end of the 19th century and the beginning of the 20th; however, none arrived at a consensus. Apart from an article written by Taylor & Descola (1981), suggesting a relationship with the Jivaroan language family, little to nothing has been said about it for the last half of the 20th century and the last decades. In the present article, a summary of the principal accounts on the language and its people between the 19th and the 20th century will be given, followed by a corpus analysis in which the materials available in Mayna and Kawapanan, mainly prayers collected by Hervás (1787) and Teza (1868), will be analysed and compared for the first time in light of recent analyses in the new-born field called Kawapanan linguistics (Barraza de García 2005a,b; Valenzuela-Bismarck 2011a,b , Valenzuela 2013; Rojas-Berscia 2013, 2014; Madalengoitia-Barúa 2013; Farfán-Reto 2012), in order to test its affiliation to the Kawapanan language family, as claimed by Beuchat & Rivet (1909) and account for its place in the dialectology of this language family.

Abstract

This paper deals with the Shawi nominalizing suffixes -su’~-ru’~-nu’ ‘general nominalizer’, -napi/-te’/-tun‘performer/agent nominalizer’, -pi’‘patient nominalizer’, and -nan ‘instrument nominalizer’. The goal of this article is to provide a description of nominalization in Shawi. Throughout this paper I apply the Generalized Scale Model (GSM) (Malchukov, 2006) to Shawi verbal nominalizations, with the intention of presenting a formal representation that will provide a basis for future areal and typological studies of nominalization. In addition, I dialogue with Shibatani’s model to see how the loss or gain of categories correlates with the lexical or grammatical nature of nominalizations. strong nominalization in Shawi correlates with lexical nominalization, whereas weak nominalizations correlate with grammatical nominalization. A typology which takes into account the productivity of the nominalizers is also discussed.

Abstract

During language comprehension, listeners often anticipate upcoming information. This can draw listeners’ overt attention to visually presented objects before the objects are referred to. We investigated to what extent the anticipatory mechanisms involved in such language-mediated attention rely on specific verbal factors and on processes shared with other domains of cognition. Participants listened to sentences ending in a highly predictable word (e.g., “In 1969 Neil Armstrong was the first man to set foot on the moon”) while viewing displays containing three unrelated distractor objects and a critical object, which was either the target object (e.g., a moon), or an object with a similar shape (e.g., a tomato), or an unrelated control object (e.g., rice). Language-mediated anticipatory eye movements to targets and shape competitors were observed. Importantly, looks to the shape competitor were systematically related to individual differences in anticipatory attention, as indexed by a spatial cueing task: Participants whose responses were most strongly facilitated by predictive arrow cues also showed the strongest effects of predictive language input on their eye movements. By contrast, looks to the target were related to individual differences in vocabulary size and verbal fluency. The results suggest that verbal and nonverbal factors contribute to different types of language-mediated eye movement. The findings are consistent with multiple-mechanism accounts of predictive language processing.

Abstract

In a number of languages, prosody is used to highlight new information (or focus). In Dutch, focus is marked by accentuation, whereby focal constituents are accented and post-focal constituents are de-accented. Even if pausing is not traditionally seen as a cue to focus in Dutch, several previous studies have pointed to a possible relationship between pausing and information structure. Considering that Dutch-speaking 4 to 5 year olds are not yet completely proficient in using accentuation for focus and that children generally pause more than adults, we asked whether pausing might be an available parameter for children to manipulate for focus. Sentences with varying focus structure were elicited from 10 Dutch-speaking 4 to 5 year olds and 9 Dutch-speaking adults by means of a picture-matching game. Comparing pause durations before focal and non-focal targets showed pre-target pauses to be significantly longer when the targets were focal than when they were not. Notably, the use of pausing was more robust in the children than in the adults, suggesting that children exploit pausing to mark focus more generally than adults do, at a stage where their mastery of the canonical cues to focus is still developing. © The Author(s) 2015

Abstract

This article describes the interactional patterns and linguistic structures associated with other-initiated repair, as observed in a corpus of video recorded conversation in the Italian language (Romance). The article reports findings specific to the Italian language from the comparative project that is the topic of this special issue. While giving an overview of all the major practices for other-initiation of repair found in this language, special attention is given to (i) the functional distinctions between different open strategies (interjection, question words, formulaic), and (ii) the role of intonation in discriminating alternative restricted strategies, with a focus on different contour types used to produce repetitions.

Abstract

Among the strategies used by people to request others to do things, there is a particular family defined as pre-requests. The typical function of a pre-request is to check whether some precondition obtains for a request to be successfully made. A form like the Italian interrogative hai x ‘do you have x’, for example, is used to ask if an object is available — a requirement for the object to be transferred or manipulated. But what does it mean exactly to make a pre-request? What difference does it make compared to issuing a request proper? In this article, I address these questions by examining the use of hai x ‘do you have x’ interrogatives in a corpus of informal Italian interaction. Drawing on methods from conversation analysis and linguistics, I show that the status of hai x as a pre-request is reflected in particular properties in the domains of preference and sequence organisation, specifically in the design of blocking responses to the pre-request, and in the use of go-ahead responses, which lead to the expansion of the request sequence. This study contributes to current research on requesting as well as on sequence organisation by demonstrating the response affordances of pre-requests and by furthering our understanding of the processes of sequence expansion.

Abstract

People across the world make requests every day. We constantly rely on others to get by in the small and big practicalities of everyday life, be it getting the salt, moving a sofa, or cooking a meal. It has long been noticed that when we ask others for help we use a wide range of forms drawing on various resources afforded by our language and body. To get another to pass the salt, for example, we may say ‘Pass the salt’, or ask ‘Can you pass me the salt?’, or simply point to the salt. What do different forms of requesting give us? The short answer is that they allow us to manage different social relations. But what kind of relations? While prior research has mostly emphasised the role of long-term asymmetries like people’s social distance and relative power, this thesis puts at centre stage social relations and dimensions emerging in the moment-by-moment flow of everyday interaction. These include how easy or hard the action requested is to anticipate for the requestee, whether the action requested contributes to a joint project or serves an individual one, whether the requestee may be unwilling to do it, and how obvious or equivocal it is that a certain person or another should be involved in the action. The study focuses on requests made in everyday informal interactions among speakers of Italian. It involves over 500 instances of requests sampled from a diverse corpus of video recordings, and draws on methods from conversation analysis, linguistics and multimodal analysis. A qualitative analysis of the data is supported by quantitative measures of the distribution of linguistic and interactional features, and by the use of inferential statistics to test the generalizability of some of the patterns observed. The thesis aims to contribute to our understanding of both language and social interaction by showing that forms of requesting constitute a system, organised by a set of recurrent social-interactional concerns.

Abstract

Despite the importance of effective pain communication, talking about pain represents a major challenge for patients and clinicians because pain is a private and subjective experience. Focusing primarily on acute pain, this article considers the limitations of current methods of obtaining information about the sensory characteristics of pain and suggests that spontaneously produced “co-speech hand gestures” may constitute an important source of information here. Although this is a relatively new area of research, we present recent empirical evidence that reveals that co-speech gestures contain important information about pain that can both add to and clarify speech. Following this, we discuss how these findings might eventually lead to a greater understanding of the sensory characteristics of pain, and to improvements in treatment and support for pain sufferers. We hope that this article will stimulate further research and discussion of this previously overlooked dimension of pain communication

Abstract

This study investigated the extent to which 3- and 4-year-old children may rely on associative memory representations to pass an unexpected-contents false-belief task. In Experiment 1, 4-year-olds performed at chance in both a standard Smarties task and a modified version highlighting the secrecy of the contents of the tube. These results were interpreted as evidence that having to infer the answer to a false-belief question (without relying on memory representations) is generally difficult for preschool children. In Experiments 2a, 2b, and 2c, 3-year-olds were tested at 3-month intervals during their first year of preschool and showed better performance in a narrative version of the Smarties task (chance level) than in the standard version (below-chance level). These children performed even better in an associative version of the narrative task (above-chance level) where they could form a memory representation associating the protagonist with the expected contents of a box. The results of a true-belief control suggest that some of these children may have relied on their memory of the protagonist’s preference for the original contents of the box (rather than their understanding of what the protagonist was expecting to find inside). This suggests that when 3-year-olds passed the associative unexpected-contents task, some may have been keeping track of the protagonist’s initial preference and not only (or not necessarily) of the protagonist’s false belief. These results are interpreted in the light of current accounts of Theory of Mind development and failed replications of verbal false-belief tasks.

Abstract

The Violation-of-Expectation paradigm is a widespread paradigm in infancy research that relies on looking time as an index of surprise. This methodological review aims to increase the reliability of future VoE studies by proposing to standardize reporting practices in this literature. I review 15 VoE studies on false-belief reasoning, which used a variety of experimental parameters. An analysis of the distribution of p-values across experiments suggests an absence of p-hacking. However, there are potential concerns with the accuracy of their measures of infants’ attention, as well as with the lack of a consensus on the parameters that should be used to set up VoE studies. I propose that (i) future VoE studies ought to report not only looking times (as a measure of attention) but also looking-away times (as an equally important measure of distraction); (ii) VoE studies must offer theoretical justification for the parameters they use, and (iii) when parameters are selected through piloting, pilot data must be reported in order to understand how parameters were selected. Future VoE studies ought to maximize the accuracy of their measures of infants’ attention since the reliability of their results and the validity of their conclusions both depend on the accuracy of their measures.

Abstract

There is an ongoing debate, both in philosophy and psychology, as to whether people are able to automatically infer what others may know, or whether they can only derive belief inferences by deploying cognitive resources. Evidence from laboratory tasks, often involving false beliefs or visual-perspective taking, has suggested that belief inferences are cognitively costly, controlled processes. Here we suggest that in everyday conversation, belief reasoning is pervasive and therefore potentially automatic in some cases. To test this hypothesis, we conducted two pre-registered self-paced reading experiments (N1 = 91, N2 = 89). The results of these experiments showed that participants slowed down when a stranger commented ‘That greasy food is bad for your ulcer’ relative to conditions where a stranger commented on their own ulcer or a friend made either comment – none of which violated participants’ common-ground expectations. We conclude that Theory of Mind models need to account for belief reasoning in conversation as it is at the center of everyday social interaction

Abstract

A pragmatic account of referential communication is developed which presents an alternative to traditional Gricean accounts by focusing on cooperativeness and efficiency, rather than informativity. The results of four language-production experiments support the view that speakers can be cooperative when producing redundant adjectives, doing so more often when color modification could facilitate the listener's search for the referent in the visual display (Experiment 1a). By contrast, when the listener knew which shape was the target, speakers did not produce redundant color adjectives (Experiment 1b). English speakers used redundant color adjectives more often than Spanish speakers, suggesting that speakers are sensitive to the differential efficiency of prenominal and postnominal modification (Experiment 2). Speakers were also cooperative when using redundant size adjectives (Experiment 3). Overall, these results show how discriminability affects a speaker's choice of referential expression above and beyond considerations of informativity, supporting the view that redundant speakers can be cooperative.

Abstract

In standard Relevance Theory, hyperbole and metaphor are categorized together as loose uses of language, on a continuum with approximations, category extensions and other cases of loosening/broadening of meaning. Specifically, it is claimed that there are no interesting differences (in either interpretation or processing) between hyperbolic and metaphorical uses (Sperber & Wilson, 2008). In recent work, we have set out to provide a more fine-grained articulation of the similarities and differences between hyperbolic and metaphorical uses and their relation to literal uses (Carston & Wearing, 2011, 2014). We have defended the view that hyperbolic use involves a shift of magnitude along a dimension which is intrinsic to the encoded meaning of the hyperbole vehicle, while metaphor involves a multi-dimensional qualitative shift away from the encoded meaning of the metaphor vehicle. In this article, we present three experiments designed to test the predictions of this analysis, using a variety of tasks (paraphrase elicitation, self-paced reading and sentence verification). The results of the study support the view that hyperbolic and metaphorical interpretations, despite their commonalities as loose uses of language, are significantly different.

Abstract

Two studies investigated whether speaking mode influences the way German speakers mark the information status of discourse referents in nuclear position. In Study 1, speakers produced narrations spontaneously on the basis of picture stories in which the information status of referents (new, accessible and given) was systematically varied. In Study 2, speakers saw the same pictures, but this time accompanied by text to be read out. Clear differences were found depending on speaking mode: In spontaneous speech, speakers always accented new referents. They did not use different pitch accent types to differentiate between new and accessible referents, nor did they always deaccent given referents. In addition, speakers often made use of low pitch accents in combination with high boundary tones to indicate continuity. In contrast to this, read speech was characterized by low boundary tones, consistent deaccentuation of given referents and the use of H+L* and H+!H* accents, for both new and accessible referents. The results are discussed in terms of the function of intonational features in communication. It is argued that reading intonation is not comparable to intonation in spontaneous speech, and that this has important consequences also for our choice of methodology in child language acquisition research

Abstract

We study how people attend to and memorize endings of events that differ in the degree to which objects in them are affected by an action: Resultative events show objects that undergo a visually salient change in state during the course of the event (peeling a potato), and non‐resultative events involve objects that undergo no, or only partial state change (stirring in a pan). We investigate general cognitive principles, and potential language‐specific influences, in verbal and nonverbal event encoding and memory, across two experiments with Dutch and Estonian participants. Estonian marks a viewer's perspective on an event's result obligatorily via grammatical case on direct object nouns: Objects undergoing a partial/full change in state in an event are marked with partitive/accusative case, respectively. Therefore, we hypothesized increased saliency of object states and event results in Estonian speakers, as compared to speakers of Dutch. Findings show (a) a general cognitive principle of attending carefully to endings of resultative events, implying cognitive saliency of object states in event processing; (b) a language‐specific boost on attention and memory of event results under verbal task demands in Estonian speakers. Results are discussed in relation to theories of event cognition, linguistic relativity, and thinking for speaking.

Abstract

Emotions are often expressed metaphorically, and both emotion and metaphor are ways through which abstract meaning can be grounded in language. Here we investigate specifically whether motion-related verbs when used metaphorically are differentially sensitive to a preceding emotional context, as compared to when they are used in a literal manner. Participants read stories that ended with ambiguous action/motion sentences (e.g., he got it), in which the action/motion could be interpreted metaphorically (he understood the idea) or literally (he caught the ball) depending on the preceding story. Orthogonal to the metaphorical manipulation, the stories were high or low in emotional content. The results showed that emotional context modulated the neural response in visual motion areas to the metaphorical interpretation of the sentences, but not to their literal interpretations. In addition, literal interpretations of the target sentences led to stronger activation in the visual motion areas as compared to metaphorical readings of the sentences. We interpret our results as suggesting that emotional context specifically modulates mental simulation during metaphor processing

Abstract

Languages have complex and varied means for representing points of view, including constructions that can express multiple perspectives on the same event. This paper presents data on two evidential constructions in the language Duna (Papua New Guinea) that imply features of both speaker and addressee knowledge simultaneously. I discuss how talking about an addressee’s knowledge can occur in contexts of both coercion and co-operation, and, while apparently empathetic, can provide a covert way to both manipulate the addressee’s attention and express speaker stance. I speculate that ultimately, however, these multiple perspective constructions may play a pro-social role in building or repairing the interlocutors’ common ground.

Abstract

To what extent does perceptual language reflect universals of experience and cognition, and to what extent is it shaped by particular cultural preoccupations? This paper investigates the universality~relativity of perceptual language by examining the use of basic perception terms in spontaneous conversation across 13 diverse languages and cultures. We analyze the frequency of perception words to test two universalist hypotheses: that sight is always a dominant sense, and that the relative ranking of the senses will be the same across different cultures. We find that references to sight outstrip references to the other senses, suggesting a pan-human preoccupation with visual phenomena. However, the relative frequency of the other senses was found to vary cross-linguistically. Cultural relativity was conspicuous as exemplified by the high ranking of smell in Semai, an Aslian language. Together these results suggest a place for both universal constraints and cultural shaping of the language of perception.

Abstract

Subcortical brain structures are integral to motion, consciousness, emotions and learning. We identified common genetic variation related to the volumes of the nucleus accumbens, amygdala, brainstem, caudate nucleus, globus pallidus, putamen and thalamus, using genome-wide association analyses in almost 40,000 individuals from CHARGE, ENIGMA and UK Biobank. We show that variability in subcortical volumes is heritable, and identify 48 significantly associated loci (40 novel at the time of analysis). Annotation of these loci by utilizing gene expression, methylation and neuropathological data identified 199 genes putatively implicated in neurodevelopment, synaptic signaling, axonal transport, apoptosis, inflammation/infection and susceptibility to neurological disorders. This set of genes is significantly enriched for Drosophila orthologs associated with neurodevelopmental phenotypes, suggesting evolutionarily conserved mechanisms. Our findings uncover novel biology and potential drug targets underlying brain development and disease.

Abstract

The epigenetic enzyme p300/CBP-associated factor (PCAF) belongs to the GCN5-related N-acetyltransferase (GNAT) family together with GCN5. Although its transcriptional and post-translational function is well characterized, little is known about its properties as regulator of cell metabolism. Here, we report the mitochondrial localization of PCAF conferred by an 85 aa mitochondrial targeting sequence (MTS) at the N-terminal region of the protein. In mitochondria, one of the PCAF targets is the isocitrate dehydrogenase 2 (IDH2) acetylated at lysine 180. This PCAF-regulated post-translational modification might reduce IDH2 affinity for isocitrate as a result of a conformational shift involving predictively the tyrosine at position 179. Site-directed mutagenesis and functional studies indicate that PCAF regulates IDH2, acting at dual level during myoblast differentiation: at a transcriptional level together with MyoD, and at a post-translational level by direct modification of lysine acetylation in mitochondria. The latter event determines a decrease in IDH2 function with negative consequences on muscle fiber formation in C2C12 cells. Indeed, a MTS-deprived PCAF does not localize into mitochondria, remains enriched into the nucleus, and contributes to a significant increase of muscle-specific gene expression enhancing muscle differentiation. The role of PCAF in mitochondria is a novel finding shedding light on metabolic processes relevant to early muscle precursor differentiation.—Savoia, M., Cencioni, C., Mori, M., Atlante, S., Zaccagnini, G., Devanna, P., Di Marcotullio, L., Botta, B., Martelli, F., Zeiher, A. M., Pontecorvi, A., Farsetti, A., Spallotta, F., Gaetano, C. P300/CBP-associated factor regulates transcription and function of isocitrate dehydrogenase 2 during muscle differentiation.

Abstract

Distributing the spoils of a joint enterprise on the basis of work contribution or relative productivity seems natural to the modern Western mind. But such notions of merit-based distributive justice may be culturally constructed norms that vary with the social and economic structure of a group. In the present research, we showed that children from three different cultures have very different ideas about distributive justice. Whereas children from a modern Western society distributed the spoils of a joint enterprise precisely in proportion to productivity, children from a gerontocratic pastoralist society in Africa did not take merit into account at all. Children from a partially hunter-gatherer, egalitarian African culture distributed the spoils more equally than did the other two cultures, with merit playing only a limited role. This pattern of results suggests that some basic notions of distributive justice are not universal intuitions of the human species but rather culturally constructed behavioral norms.

Abstract

This study examined the use of fricative noise information and coarticulatory cues for categorization of word-final fricatives [s] and [f] by younger and older Dutch listeners alike. Particularly, the effect of information loss in the higher frequencies on the use of these two cues for fricative categorization was investigated. If information in the higher frequencies is less strongly available, fricative identification may be impaired or listeners may learn to focus more on coarticulatory information. The present study investigates this second possibility. Phonetic categorization results showed that both younger and older Dutch listeners use the primary cue fricative noise and the secondary cue coarticulatory information to distinguish
word-final [f] from [s]. Individual hearing sensitivity in the older listeners modified the use of fricative noise information, but did not modify the use of coarticulatory information. When high-frequency information was filtered out from the speech signal, fricative noise could no longer be used by the younger and older adults. Crucially, they also did not learn to rely more on coarticulatory information as a compensatory cue for fricative categorization. This suggests that listeners do not readily show compensatory use of this secondary cue to fricative identity when fricative categorization becomes difficult.

Abstract

This study investigates two variables that may modify lexically-guided perceptual learning: individual hearing sensitivity and attentional abilities. Older Dutch listeners (aged 60+, varying from good hearing to mild-to-moderate high-frequency hearing loss) were tested on a lexically-guided perceptual learning task using the contrast [f]-[s]. This contrast mainly differentiates between the two consonants in the higher frequencies, and thus is supposedly challenging for listeners with hearing loss. The analyses showed that older listeners generally engage in lexically-guided perceptual learning. Hearing loss and selective attention did not modify perceptual learning in our participant sample, while attention-switching control did: listeners with poorer attention-switching control showed a stronger perceptual learning effect. We postulate that listeners with better attention-switching control may, in general, rely more strongly on bottom-up acoustic information compared to listeners with poorer attention-switching control, making them in turn less susceptible to lexically-guided perceptual learning effects. Our results, moreover, clearly show that lexically-guided perceptual learning is not lost when acoustic processing is less accurate.

Abstract

Exposure to traumatic stress increases the odds of developing a broad range of psychiatric conditions. Genetic studies targeting multiple stress-related quantitative phenotypes may shed light on mechanisms underlying vulnerability to psychopathology in the aftermath of stressful events. We applied a multivariate genome-wide association study (GWAS) to a unique military cohort (N = 583) in which we measured biochemical and behavioral phenotypes. The availability of pre- and post-deployment measurements allowed to capture changes in these phenotypes in response to stress. For genome-wide significant loci, we performed functional annotation, phenome-wide analysis and quasi-replication in PTSD case-control GWASs. We discovered one genetic variant reaching genome-wide significant association, surviving permutation and sensitivity analyses (rs10100651, p = 9.9 × 10−9). Functional annotation prioritized the genes INTS8 and TP53INP1. A phenome-wide scan revealed a significant association of these same genes with sleeping problems, hypertension and subjective well-being. Finally, a targeted lookup revealed nominally significant association of rs10100651 in a PTSD case-control GWAS in the UK Biobank (p = 0.02). We provide comprehensive evidence from multiple resources hinting at a role of the highlighted genetic variant in the human stress response, marking the power of multivariate genome-wide analysis of quantitative measures in stress research. Future genetic and functional studies can target this locus to further assess its effects on stress mediation and its possible role in psychopathology or resilience.

Abstract

This chapter describes how speakers access words from the mental lexicon. Lexical access is a crucial
component in the process of transforming thoughts into speech. Some theories consider lexical access to be
strictly serial and discrete, while others view this process as being cascading or even interactive, i.e. the different
sub-levels influence each other. We discuss some of the evidence in favour and against these viewpoints, and
also present arguments regarding the ongoing debate on how words are selected for production. Another important
issue concerns the access to morphologically complex words such as derived and inflected words, as well as
compounds. Are these accessed as whole entities from the mental lexicon or are the parts assembled online? This
chapter tries to provide an answer to that question as well.

Abstract

Object categorization is an important cognitive adaptation, quickly providing an animal with relevant and potentially life-saving information. It can be defined as the process whereby objects that are not the same, are nonetheless grouped together according to some defining feature(s) and responded to as if they were the same. In this way, knowledge about one object, behavior or situation can be extrapolated onto another without much cost and effort. Many vertebrates including humans, monkeys, birds and teleosts have been shown to be able to categorize, with abilities varying between species and tasks. This study assessed object categorization skills in the gray bamboo shark Chiloscyllium griseum. Sharks learned to distinguish between the two categories, 'fish' versus 'snail' independently of image features and image type, i.e., black and white drawings, photographs, comics or negative images. Transfer tests indicated that sharks predominantly focused on and categorized the positive stimulus, while disregarding the negative stimulus.

Abstract

Processing of semantic information in language comprehension has been suggested to be modulated by attentional resources. Consequently, cognitive load would be expected to reduce semantic priming, but studies have yielded inconsistent results. This study investigated whether cognitive load affects semantic activation in speech processing in older adults, and whether this is modulated by individual differences in cognitive and hearing abilities. Older adults participated in an auditory continuous lexical decision task in a low-load and high-load condition. The group analysis showed only a marginally significant reduction of semantic priming in the high-load condition compared to the low-load condition. The individual differences analysis showed that semantic priming was significantly reduced under increased load in participants with poorer attention-switching control. Hence, a resource-demanding secondary task may affect the integration of spoken words into a coherent semantic representation for listeners with poorer attentional skills.

Abstract

This paper addresses the role of the adverb in Dutch direct object scrambling constructions. We report four experiments in which we investigate whether the structural position and the scope sensitivity of the adverb affect acceptability judgments of scrambling constructions and native speakers' tendency to scramble definite objects. We conclude that the type of adverb plays a key role in Dutch word ordering preferences.

Abstract

This dataset, colloquially known as the Mother Of Unification Studies (MOUS) dataset, contains multimodal neuroimaging data that has been acquired from 204 healthy human subjects. The neuroimaging protocol consisted of magnetic resonance imaging (MRI) to derive information at high spatial resolution about brain anatomy and structural connections, and functional data during task, and at rest. In addition, magnetoencephalography (MEG) was used to obtain high temporal resolution electrophysiological measurements during task, and at rest. All subjects performed a language task, during which they processed linguistic utterances that either consisted of normal or scrambled sentences. Half of the subjects were reading the stimuli, the other half listened to the stimuli. The resting state measurements consisted of 5 minutes eyes-open for the MEG and 7 minutes eyes-closed for fMRI. The neuroimaging data, as well as the information about the experimental events are shared according to the Brain Imaging Data Structure (BIDS) format. This unprecedented neuroimaging language data collection allows for the investigation of various aspects of the neurobiological correlates of language.

Abstract

Speakers are influenced by the linguistic context: hearing one syntactic alternative leads to an increased chance that the speaker will repeat this structure in the subsequent utterance (i.e., syntactic priming, or structural persistence). Top-down influences, such as whether a conversation partner (or, interlocutor) is present, may modulate the degree to which syntactic priming occurs. In the current study, we indeed show that the magnitude of syntactic alignment increases when speakers are interacting with an interlocutor as opposed to doing the experiment alone. The structural persistence effect for passive sentences is stronger in the presence of an interlocutor than when no interlocutor is present (i.e., when the participant is primed by a recording). We did not find evidence, however, that a speaker’s syntactic priming magnitude is influenced by the degree of their conversation partner’s priming magnitude. Together, these results support a mediated account of syntactic priming, in which syntactic choices are not only affected by preceding linguistic input, but also by top-down influences, such as the speakers’ communicative intent.

Abstract

This article is reproduced from the previous edition, volume 22, pp. 14879–14882, © 2001, Elsevier Ltd.

Abstract

Speakers can adapt their speech and co-speech gestures for
addressees. Here, we investigate whether this ability is
modulated by age. Younger and older adults participated in a
comic narration task in which one participant (the speaker)
narrated six short comic stories to another participant (the
addressee). One half of each story was known to both participants, the other half only to the speaker. Younger but
not older speakers used more words and gestures when narrating novel story content as opposed to known content.
We discuss cognitive and pragmatic explanations of these findings and relate them to theories of gesture production.

Abstract

Speakers can adapt their speech and co-speech gestures based on knowledge shared with an addressee (common ground-based recipient design). Here, we investigate whether these adaptations are modulated by the speaker’s age and cognitive abilities. Younger and older participants narrated six short comic stories to a same-aged addressee. Half of each story was known to both participants, the other half only to the speaker. The two age groups did not differ in terms of the number of words and narrative events mentioned per narration, or in terms of gesture frequency, gesture rate, or percentage of events expressed multimodally. However, only the younger participants reduced the amount of verbal and gestural information when narrating mutually known as opposed to novel story content. Age-related differences in cognitive abilities did not predict these differences in common ground-based recipient design. The older participants’ communicative behaviour may therefore also reflect differences in social or pragmatic goals.

Abstract

Adaptation to altered auditory feedback has been shown to induce subsequent shifts in perception. However, it is uncertain whether these perceptual changes may generalize to other speech sounds. In this experiment, we tested whether exposing the production of a vowel to altered auditory feedback affects perceptual categorization of a consonant distinction. In two sessions, participants produced CVC words containing the vowel /i/, while intermittently categorizing stimuli drawn from a continuum between "see" and "she." In the first session feedback was unaltered, while in the second session the formants of the vowel were shifted 20% towards /u/. Adaptation to the altered vowel was found to reduce the proportion of perceived /S/ stimuli. We suggest that this reflects an alteration to the sensorimotor mapping that is shared between vowels and consonants.

Abstract

In different tasks involving action perception, performance has been found to be facilitated
when the presented stimuli were produced by the participants themselves rather than by
another participant. These results suggest that the same mental representations are
accessed during both production and perception. However, with regard to spoken word perception,
evidence also suggests that listeners’ representations for speech reflect the input
from their surrounding linguistic community rather than their own idiosyncratic productions.
Furthermore, speech perception is heavily influenced by indexical cues that may lead listeners
to frame their interpretations of incoming speech signals with regard to speaker identity.
In order to determine whether word recognition evinces similar self-advantages as found in
action perception, it was necessary to eliminate indexical cues from the speech signal. We therefore asked participants to identify noise-vocoded versions of Dutch words that were based on either their own recordings or those of a statistically average speaker. The majority of participants were more accurate for the average speaker than for themselves, even after taking into account differences in intelligibility. These results suggest that the speech
representations accessed during perception of noise-vocoded speech are more reflective
of the input of the speech community, and hence that speech perception is not necessarily based on representations of one’s own speech.

Abstract

We tested whether statistical averageness (SA) at the level of the individual speaker could predict a speaker’s intelligibility. 28 female and 21 male speakers of Dutch were recorded producing 336 sentences,
each containing two target nouns. Recordings were compared to those of all other same-sex speakers using dynamic time warping (DTW). For each sentence, the DTW distance constituted a metric
of phonetic distance from one speaker to all other speakers. SA comprised the average of these distances. Later, the same participants performed a word recognition task on the target nouns in the same sentences, under three degraded listening conditions. In all three conditions, accuracy increased with SA. This held even when participants listened to their own utterances. These findings suggest that listeners process speech with respect to the statistical
properties of the language spoken in their community, rather than using their own speech as a reference

Abstract

Background

Voluntary shifts of visuospatial attention are associated with a lateralization of parieto-occipital alpha power (7-13Hz), i.e. higher power in the hemisphere ipsilateral and lower power contralateral to the locus of attention. Recent noninvasive neuromodulation studies demonstrated that alpha power can be experimentally increased using transcranial alternating current stimulation (tACS).
Objective/Hypothesis

We hypothesized that tACS at alpha frequency over the left parietal cortex induces shifts of attention to the left hemifield. However, spatial attention shifts not only occur voluntarily (endogenous/ top-down), but also stimulus-driven (exogenous/ bottom-up). To study the task-specificity of the potential effects of tACS on attentional processes, we administered three conceptually different spatial attention tasks.
Methods

36 healthy volunteers were recruited from an academic environment. In two separate sessions, we applied either high-density tACS at 10Hz, or sham tACS, for 35–40 minutes to their left parietal cortex. We systematically compared performance on endogenous attention, exogenous attention, and stimulus detection tasks.
Results

In the endogenous attention task, a greater leftward bias in reaction times was induced during left parietal 10Hz tACS as compared to sham. There were no stimulation effects in either the exogenous attention or the stimulus detection task.
Conclusion

The study demonstrates that high-density tACS at 10Hz can be used to modulate visuospatial attention performance. The tACS effect is task-specific, indicating that not all forms of attention are equally susceptible to the stimulation.