Publications

Abstract

-* indicates shared first authorship -
The present study investigated the effects of selective attention on the processing of morphosyntactic errors in unattended parts of speech. Two groups of German native (L1) speakers participated in the present study. Participants listened to sentences in which irregular verbs were manipulated in three different conditions (correct, incorrect but attested ablaut pattern, incorrect and crosslinguistically unattested ablaut pattern). In order to track fast dynamic neural reactions to the stimuli, electroencephalography was used. After each sentence, participants in Experiment 1 performed a semantic judgement task, which deliberately distracted the participants from the syntactic manipulations and directed their attention to the semantic content of the sentence. In Experiment 2, participants carried out a syntactic judgement task, which put their attention on the critical stimuli. The use of two different attentional tasks allowed for investigating the impact of selective attention on speech processing and whether morphosyntactic processing steps are performed automatically. In Experiment 2, the incorrect attested condition elicited a larger N400 component compared to the correct condition, whereas in Experiment 1 no differences between conditions were found. These results suggest that the processing of morphosyntactic violations in irregular verbs is not entirely automatic but seems to be strongly affected by selective attention.

Abstract

Background Thirty-two common variants associated with body mass index (BMI) have been identified in genome-wide association studies, explaining ∼1.45% of BMI variation in general population cohorts. We performed a genome-wide association study in a sample of young adults enriched for extremely overweight individuals. We aimed to identify new loci associated with BMI and to ascertain whether using an extreme sampling design would identify the variants known to be associated with BMI in general populations. Methodology/Principal Findings From two large Danish cohorts we selected all extremely overweight young men and women (n = 2,633), and equal numbers of population-based controls (n = 2,740, drawn randomly from the same populations as the extremes, representing ∼212,000 individuals). We followed up novel (at the time of the study) association signals (p<}0.001) from the discovery cohort in a genome-wide study of 5,846 Europeans, before attempting to replicate the most strongly associated 28 SNPs in an independent sample of Danish individuals (n = 20,917) and a population-based cohort of 15-year-old British adolescents (n = 2,418). Our discovery analysis identified SNPs at three loci known to be associated with BMI with genome-wide confidence (P{<}5×10−8; FTO, MC4R and FAIM2). We also found strong evidence of association at the known TMEM18, GNPDA2, SEC16B, TFAP2B, SH2B1 and KCTD15 loci (p{<}0.001), and nominal association (p{<0.05) at a further 8 loci known to be associated with BMI. However, meta-analyses of our discovery and replication cohorts identified no novel associations. Significance Our results indicate that the detectable genetic variation associated with extreme overweight is very similar to that previously found for general BMI. This suggests that population-based study designs with enriched sampling of individuals with the extreme phenotype may be an efficient method for identifying common variants that influence quantitative traits and a valid alternative to genotyping all individuals in large population-based studies, which may require tens of thousands of subjects to achieve similar power.

Abstract

Research into bilingual language production has identified a language control network that subserves control operations when bilinguals produce speech. Here we explore which brain areas are recruited for control purposes in bilingual language comprehension. In two experimental fMRI sessions, Dutch-English unbalanced bilinguals read words that differed in cross-linguistic form and meaning overlap across their two languages. The need for control operations was further manipulated by varying stimulus list composition across the two experimental sessions. We observed activation of the language control network in bilingual language comprehension as a function of both cross-linguistic form and meaning overlap and stimulus list composition. These findings suggest that the language control network is shared across bilingual language production and comprehension. We argue that activation of the language control network in language comprehension allows bilinguals to quickly and efficiently grasp the context-relevant meaning of words.

Abstract

This paper introduces virtual reality as an experimental method for the language sciences and provides a review of recent studies using the method to answer fundamental, psycholinguistic research questions. It is argued that virtual reality demonstrates that ecological validity and
experimental control should not be conceived of as two extremes on a continuum, but rather as two orthogonal factors. Benefits of using virtual reality as an experimental method include that in a virtual environment, as in the real world, there is no artificial spatial divide between participant and stimulus. Moreover, virtual reality experiments do not necessarily have to include a repetitive trial structure or an unnatural experimental task. Virtual agents outperform experimental confederates in terms of the consistency and replicability of their behaviour, allowing for reproducible science across participants and research labs. The main promise of virtual reality as a tool for the experimental language sciences, however, is that it shifts theoretical focus towards the interplay between different modalities (e.g., speech, gesture, eye gaze, facial expressions) in dynamic and communicative real-world environments, complementing studies that focus on one modality (e.g. speech) in isolation.

Abstract

A long‐standing question in child language research concerns how children achieve mature syntactic knowledge in the face of a complex linguistic environment. A widely accepted view is that this process involves extracting distributional regularities from the environment in a manner that is incidental and happens, for the most part, without the learner's awareness. In this way, the debate speaks to two associated but separate literatures in language acquisition: statistical learning and implicit learning. Both fields have explored this issue in some depth but, at present, neither the results from the infant studies used by the statistical learning literature nor the artificial grammar learning tasks studies from the implicit learning literature can be used to fully explain how children's syntax becomes adult‐like. In this work, we consider an alternative explanation—that children use error‐based learning to become mature syntax users. We discuss this proposal in the light of the behavioral findings from structural priming studies and the computational findings from Chang, Dell, and Bock's (2006) dual‐path model, which incorporates properties from both statistical and implicit learning, and offers an explanation for syntax learning and structural priming using a common error‐based learning mechanism. We then turn our attention to future directions for the field, here suggesting how structural priming might inform the statistical learning and implicit learning literature on the nature of the learning mechanism.

Abstract

It is becoming increasingly clear that the way that children acquire cognitive representations
depends critically on how their processing system is developing. In particular, recent studies
suggest that individual differences in language processing speed play an important role in explaining
the speed with which children acquire language. Inconsistencies across studies, however,
mean that it is not clear whether this relationship is causal or correlational, whether it is
present right across development, or whether it extends beyond word learning to affect other
aspects of language learning, like syntax acquisition. To address these issues, the current study
used the looking-while-listening paradigm devised by Fernald, Swingley, and Pinto (2001) to test
the speed with which a large longitudinal cohort of children (the Language 0–5 Project) processed
language at 19, 25, and 31 months of age, and took multiple measures of vocabulary (UKCDI,
Lincoln CDI, CDI-III) and syntax (Lincoln CDI) between 8 and 37 months of age. Processing
speed correlated with vocabulary size - though this relationship changed over time, and was
observed only when there was variation in how well the items used in the looking-while-listening
task were known. Fast processing speed was a positive predictor of subsequent vocabulary
growth, but only for children with smaller vocabularies. Faster processing speed did, however,
predict faster syntactic growth across the whole sample, even when controlling for concurrent
vocabulary. The results indicate a relatively direct relationship between processing speed and
syntactic development, but point to a more complex interaction between processing speed, vocabulary
size and subsequent vocabulary growth.

Abstract

Neste artigo fazemos uma revisão breve de investigações actuais com técnicas comportamentais e de neuroimagem funcional sobre a aprendizagem de uma linguagem artificial em crianças e adultos. Na secção final, discutimos uma possível associação entre dislexia e aprendizagem implícita. Resultados recentes sugerem que a presença de um défice ao nível da aprendizagem implícita pode contribuir para as dificuldades de leitura e escrita observadas em indivíduos disléxicos.

Abstract

Coarse-to-fine theories of vision propose that the coarse information carried by the low spatial frequencies (LSF) of visual input guides the integration of finer, high spatial frequency (HSF) detail. Whether and how LSF modulates HSF processing in naturalistic broad-band stimuli is still unclear. Here we used multivariate decoding of EEG signals to separate the respective contribution of LSF and HSF to the neural response evoked by broad-band images. Participants viewed images of human faces, monkey faces and phase-scrambled versions that were either broad-band or filtered to contain LSF or HSF. We trained classifiers on EEG scalp-patterns evoked by filtered scrambled stimuli and evaluated the derived models on broad-band scrambled and intact trials. We found reduced HSF contribution when LSF was informative towards image content, indicating that coarse information does guide the processing of fine detail, in line with coarse-to-fine theories. We discuss the potential cortical mechanisms underlying such coarse-to-fine feedback.

Abstract

Background

Noncoding RNA (ncRNA) has been recognized as an important regulator of gene expression networks in Bacteria and Eucaryota. Little is known about ncRNA in thermococcal archaea except for the eukaryotic-like C/D and H/ACA modification guide RNAs.
Results

Using a combination of in silico and experimental approaches, we identified and characterized novel P. abyssi ncRNAs transcribed from 12 intergenic regions, ten of which are conserved throughout the Thermococcales. Several of them accumulate in the late-exponential phase of growth. Analysis of the genomic context and sequence conservation amongst related thermococcal species revealed two novel P. abyssi ncRNA families. The CRISPR family is comprised of crRNAs expressed from two of the four P. abyssi CRISPR cassettes. The 5'UTR derived family includes four conserved ncRNAs, two of which have features similar to known bacterial riboswitches. Several of the novel ncRNAs have sequence similarities to orphan OrfB transposase elements. Based on RNA secondary structure predictions and experimental results, we show that three of the twelve ncRNAs include Kink-turn RNA motifs, arguing for a biological role of these ncRNAs in the cell. Furthermore, our results show that several of the ncRNAs are subjected to processing events by enzymes that remain to be identified and characterized.
Conclusions

This work proposes a revised annotation of CRISPR loci in P. abyssi and expands our knowledge of ncRNAs in the Thermococcales, thus providing a starting point for studies needed to elucidate their biological function.

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

Disagreement exists about whether lexical selection in word production is a competitive process. Competition predicts semanticinterference from distractor words in immediate but not in delayed picture naming. In contrast, Janssen, Schirm, Mahon, and Caramazza (2008) obtained semanticinterference in delayed picture naming when participants had to decide between picture naming and oral reading depending on the distractor word’s colour. We report three experiments that examined the role of such taskdecisions. In a single-task situation requiring picture naming only (Experiment 1), we obtained semanticinterference in immediate but not in delayednaming. In a task-decision situation (Experiments 2 and 3), no semantic effects were obtained in immediate and delayed picture naming and word reading using either the materials of Experiment 1 or the materials of Janssen et al. (2008). We present an attentional account in which taskdecisions may hide or reveal semanticinterference from lexical competition depending on the amount of parallelism between task-decision and picture–word processing.

Abstract

Defeasible inferences are inferences that can be revised in the light of new information. Although defeasible inferences are pervasive in everyday communication, little is known about how and when they are processed by the brain. This study examined the electrophysiological signature of defeasible reasoning using a modified version of the suppression task. Participants were presented with conditional inferences (of the type “if p, then q; p, therefore q”) that were preceded by a congruent or a disabling context. The disabling context contained a possible exception or precondition that prevented people from drawing the conclusion. Acceptability of the conclusion was indeed lower in the disabling condition compared to the congruent condition. Further, we found a large sustained negativity at the conclusion of the disabling condition relative to the congruent condition, which started around 250 msec and was persistent throughout the entire epoch. Possible accounts for the observed effect are discussed.

Abstract

Two groups of participants were trained to perceive an ambiguous sound [s/f] as either /s/ or /f/ based on lexical bias: One group heard the ambiguous fricative in /s/-final words, the other in /f/-final words. This kind of exposure leads to a recalibration of the /s/-/f/ contrast [e.g., 4]. In order to investigate when and how this recalibration emerges, test trials were interspersed among training and filler trials. The learning effect needed at least 10 clear training items to arise. Its emergence seemed to occur in a rather step-wise fashion. Learning did not improve much after it first appeared. It is likely, however, that the early test trials attracted participants' attention and therefore may have interfered with the learning process.

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

OBJECTIVE: There is overlap between an autistic and hyperactive-inattentive symptomatology when studied cross-sectionally. This study is the first to examine the longitudinal pattern of association between social-communication deficits and hyperactive-inattentive symptoms in the general population, from childhood through adolescence. We explored the interrelationship between trajectories of co-occurring symptoms, and sought evidence for shared prenatal/perinatal risk factors. METHOD: Study participants were 5,383 singletons of white ethnicity from the Avon Longitudinal Study of Parents and Children (ALSPAC). Multiple measurements of hyperactive-inattentive traits (Strengths and Difficulties Questionnaire) and autistic social-communication impairment (Social Communication Disorder Checklist) were obtained between 4 and 17 years. Both traits and their trajectories were modeled in parallel using latent class growth analysis (LCGA). Trajectory membership was subsequently investigated with respect to prenatal/perinatal risk factors. RESULTS: LCGA analysis revealed two distinct social-communication trajectories (persistently impaired versus low-risk) and four hyperactive-inattentive trait trajectories (persistently impaired, intermediate, childhood-limited and low-risk). Autistic symptoms were more stable than those of attention-deficit/hyperactivity disorder (ADHD) behaviors, which showed greater variability. Trajectories for both traits were strongly but not reciprocally interlinked, such that the majority of children with a persistent hyperactive-inattentive symptomatology also showed persistent social-communication deficits but not vice versa. Shared predictors, especially for trajectories of persistent impairment, were maternal smoking during the first trimester, which included familial effects, and a teenage pregnancy. CONCLUSIONS: Our longitudinal study reveals that a complex relationship exists between social-communication and hyperactive-inattentive traits. Patterns of association change over time, with corresponding implications for removing exclusivity criteria for ASD and ADHD, as proposed for DSM-5.

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

Objective—The vascular competence of human-derived hematopoietic progenitors for postnatal vascularization is still poorly characterized. It is unclear whether, in the absence of ischemia, hematopoietic progenitors participate in neovascularization and whether they play a role in new blood vessel formation by incorporating into developing vessels or by a paracrine action. Methods and Results—In the present study, human cord blood–derived CD34+ (hCD34+) cells were transplanted into pre- and postgastrulation zebrafish embryos and in an adult vascular regeneration model induced by caudal fin amputation. When injected before gastrulation, hCD34+ cells cosegregated with the presumptive zebrafish hemangioblasts, characterized by Scl and Gata2 expression, in the anterior and posterior lateral mesoderm and were involved in early development of the embryonic vasculature. These morphogenetic events occurred without apparent lineage reprogramming, as shown by CD45 expression. When transplanted postgastrulation, hCD34+ cells were recruited into developing vessels, where they exhibited a potent paracrine proangiogenic action. Finally, hCD34+ cells rescued vascular defects induced by Vegf-c in vivo targeting and enhanced vascular repair in the zebrafish fin amputation model. Conclusion—These results indicate an unexpected developmental ability of human-derived hematopoietic progenitors and support the hypothesis of an evolutionary conservation of molecular pathways involved in endothelial progenitor differentiation in vivo.

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

The current study examined the acquisition of relative clauses (RCs) in Persian-speaking children. Persian is a relatively unique data point in crosslinguistic research in acquisition because it is a head-final language with post-nominal RCs. Children (N = 51) aged 2 to 7 years completed a picture-selection task that tested their comprehension of subject-, object-, and genitive-RCs. The results showed that the children experienced greater difficulty processing object and genitive RCs when compared to subject RCs, suggesting that the children have particular difficulty processing sentences with non-canonical word order. The results are discussed with reference to a number of theoretical accounts proposed to account for sentence difficulty.

Abstract

Trilingual dictionary

Abstract

The authors determined the effects of changes in task demands on interpersonal and intrapersonal coordination. Participants performed a joint task in which one participant held a stick to which a circle was attached at the top (holding role), while the other held a pointer through the circle without touching its borders (pointing role). Experiment 1 investigated whether interpersonal and intrapersonal coordination varied depending on task difficulty. Results showed that interpersonal and intrapersonal coordination increased in degree and stability with increments in task difficulty. Experiment 2 explored the effects of individual constraints by increasing the balance demands of the task (one or both members of the pair stood in a less stable tandem stance). Results showed that interpersonal coordination increased in degree and stability as joint task demands increased and that coupling strength varied depending on joint and individual task constraints. In all, results suggest that interpersonal and intrapersonal coordination are affected by the nature of the task performed and the constraints it places on joint and individual performance.

Abstract

This paper identifies four reciprocal construction types in Khoekhoe (Central Khoisan). After a brief description of the morphosyntax of each construction, semantic factors governing their choice are explored. Besides lexical semantics, the number of participants, timing of symmetric subevents, and symmetric conceptualisation are shown to account for the distribution of the four partially competing reciprocal constructions.

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

Fetal akinesia refers to a broad spectrum of disorders in which the unifying feature is a reduction or lack of fetal movement. Fetal akinesias may be caused by defects at any point along the motor system pathway including the central and peripheral nervous system, the neuromuscular junction and the muscle, as well as by restrictive dermopathy or external restriction of the fetus in utero. The fetal akinesias are clinically and genetically heterogeneous, with causative mutations identified to date in a large number of genes encoding disparate parts of the motor system. However, for most patients, the molecular cause remains unidentified. One reason for this is because the tools are only now becoming available to efficiently and affordably identify mutations in a large panel of disease genes. Next-generation sequencing offers the promise, if sufficient cohorts of patients can be assembled, to identify the majority of the remaining genes on a research basis and facilitate efficient clinical molecular diagnosis. The benefits of identifying the causative mutation(s) for each individual patient or family include accurate genetic counselling and the options of prenatal diagnosis or preimplantation genetic diagnosis.

In this review, we summarise known single-gene disorders affecting the spinal cord, peripheral nerves, neuromuscular junction or skeletal muscles that result in fetal akinesia. This audit of these known molecular and pathophysiological mechanisms involved in fetal akinesia provides a basis for improved molecular diagnosis and completing disease gene discovery.

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

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

Several linkage analyses implicated the chromosome 9q22 region in attention deficit/hyperactivity disorder (ADHD), a neurodevelopmental disease with remarkable persistence into adulthood. This locus contains the brain-expressed GTP-binding RAS-like 2 gene (DIRAS2) thought to regulate neurogenesis. As DIRAS2 is a positional and functional ADHD candidate gene, we conducted an association study in 600 patients suffering from adult ADHD (aADHD) and 420 controls. Replication samples consisted of 1035 aADHD patients and 1381 controls, as well as 166 families with a child affected from childhood ADHD. Given the high degree of co-morbidity with ADHD, we also investigated patients suffering from bipolar disorder (BD) (n=336) or personality disorders (PDs) (n=622). Twelve single-nucleotide polymorphisms (SNPs) covering the structural gene and the transcriptional control region of DIRAS2 were analyzed. Four SNPs and two haplotype blocks showed evidence of association with ADHD, with nominal p-values ranging from p=0.006 to p=0.05. In the adult replication samples, we obtained a consistent effect of rs1412005 and of a risk haplotype containing the promoter region (p=0.026). Meta-analysis resulted in a significant common OR of 1.12 (p=0.04) for rs1412005 and confirmed association with the promoter risk haplotype (OR=1.45, p=0.0003). Subsequent analysis in nuclear families with childhood ADHD again showed an association of the promoter haplotype block (p=0.02). rs1412005 also increased risk toward BD (p=0.026) and cluster B PD (p=0.031). Additional SNPs showed association with personality scores (p=0.008–0.048). Converging lines of evidence implicate genetic variance in the promoter region of DIRAS2 in the etiology of ADHD and co-morbid impulsive disorders.

Abstract

An exposure-test paradigm was used to examine whether Dutch listeners can adapt their perception to non-canonical marking of lexical stress in Hungarian-accented Dutch. During exposure, one group of listeners heard only words with correct initial stress, while another group also heard examples of unstressed initial syllables that were marked by high pitch, a possible stress cue in Dutch. Subsequently, listeners’ eye movements to target-competitor pairs with segmental overlap but different stress patterns were tracked while hearing Hungarian-accented Dutch. Listeners who had heard non-canonically produced words previously distinguished target-competitor pairs faster than listeners who had only been exposed to canonical forms before. This suggests that listeners can adapt quickly to speaker-specific realizations of non-canonical lexical stress.

Abstract

Listeners can flexibly retune category boundaries of their native language to adapt to non-canonically produced phonemes. This only occurs, however, if the pronunciation peculiarities can be attributed to stable and not transient speaker-specific characteristics. Listening to someone speaking a second language, listeners could attribute non-canonical pronunciations either to the speaker or to the fact that she is modifying her categories in the second language. We investigated whether, following exposure to Dutch-accented English, Dutch listeners show effects of category retuning during test where they hear the same speaker speaking her native language, Dutch. Exposure was a lexical-decision task where either word-final [f] or [s] was replaced by an ambiguous sound. At test listeners categorized minimal word pairs ending in sounds along an [f]-[s] continuum. Following exposure to English words, Dutch listeners showed boundary shifts of a similar magnitude as following exposure to the same phoneme variants in their native language. This suggests that production patterns in a second language are deemed a stable characteristic. A second experiment suggests that category retuning also occurs when listeners are exposed to and tested with a native speaker of their second language. Listeners thus retune phoneme boundaries across languages.

Abstract

Three categorization experiments investigated whether the speaking rate of a preceding sentence influences durational cues to the perception of suprasegmental lexical-stress patterns. Dutch two-syllable word fragments had to be judged as coming from one of two longer words that matched the fragment segmentally but differed in lexical stress placement. Word pairs contrasted primary stress on either the first versus the second syllable or the first versus the third syllable. Duration of the initial or the second syllable of the fragments and rate of the preceding context (fast vs. slow) were manipulated. Listeners used speaking rate to decide about the degree of stress on initial syllables whether the syllables' absolute durations were informative about stress (Experiment 1a) or not (Experiment 1b). Rate effects on the second syllable were visible only when the initial syllable was ambiguous in duration with respect to the preceding rate context (Experiment 2). Absolute second syllable durations contributed little to stress perception (Experiment 3). These results suggest that speaking rate is used to disambiguate words and that rate-modulated stress cues are more important on initial than non-initial syllables. Speaking rate affects perception of suprasegmental information.

Abstract

A series of eye-tracking and categorization experiments investigated the use of speaking-rate information in the segmentation of Dutch ambiguous-word sequences. Juncture phonemes with ambiguous durations (e.g., [s] in 'eens (s)peer,' “once (s)pear,” [t] in 'nooit (t)rap,' “never staircase/quick”) were perceived as longer and hence more often as word-initial when following a fast than a slow context sentence. Listeners used speaking-rate information as soon as it became available. Rate information from a context proximal to the juncture phoneme and from a more distal context was used during on-line word recognition, as reflected in listeners' eye movements. Stronger effects of distal context, however, were observed in the categorization task, which measures the off-line results of the word-recognition process. In categorization, the amount of rate context had the greatest influence on the use of rate information, but in eye tracking, the rate information's proximal location was the most important. These findings constrain accounts of how speaking rate modulates the interpretation of durational cues during word recognition by suggesting that rate estimates are used to evaluate upcoming phonetic information continuously during prelexical speech processing.

Abstract

A aquisição de competências de leitura e de escrita pode ser vista como um processo formal de transmissão cultural, onde interagem factores neurobiológicos e culturais. O treino sistemático exigido pela aprendizagem da leitura e da escrita poderá produzir mudanças quantitativas e qualitativas tanto a nível cognitivo como ao nível da organização do cérebro. Estudar sujeitos iletrados e letrados representa, assim, uma oportunidade para investigar efeitos de uma aprendizagem específica no desenvolvimento cognitivo e suas bases cerebrais. Neste trabalho, revemos um conjunto de investigações comportamentais e com métodos de imagem cerebral que indicam que a literacia tem um impacto nas nossas funções cognitivas e na organização cerebral. Mais especificamente, discutiremos diferenças entre letrados e iletrados para domínios cognitivos verbais e não-verbais, sugestivas de que a arquitectura cognitiva é formatada, em parte, pela aprendizagem da leitura e da escrita. Os dados de neuroimagem funcionais e estruturais são também indicadores que a aquisição de uma ortografia alfabética interfere nos processos de organização e lateralização das funções cognitivas.

Abstract

Human societies are built on collaborative activities. Already from early childhood, human children are skillful and proficient collaborators. They recognize when they need help in solving a problem and actively recruit collaborators [ [1] and 2 F. Warneken, F. Chen and M. Tomasello, Cooperative activities in young children and chimpanzees. Child Dev., 77 (2006), pp. 640–663. | View Record in Scopus | [MPG-SFX] | | Full Text via CrossRef | Cited By in Scopus (56) [2] ]. The societies of other primates are also to some degree cooperative. Chimpanzees, for example, engage in a variety of cooperative activities such as border patrols, group hunting, and intra- and intergroup coalitionary behavior [ [3] , [4] and [5] ]. Recent studies have shown that chimpanzees possess many of the cognitive prerequisites necessary for human-like collaboration. Chimpanzees have been shown to recognize when they need help in solving a problem and to actively recruit good over bad collaborators [ [6] and [7] ]. However, cognitive abilities might not be all that differs between chimpanzees and humans when it comes to cooperation. Another factor might be the motivation to engage in a cooperative activity. Here, we hypothesized that a key difference between human and chimpanzee collaboration—and so potentially a key mechanism in the evolution of human cooperation—is a simple preference for collaborating (versus acting alone) to obtain food. Our results supported this hypothesis, finding that whereas children strongly prefer to work together with another to obtain food, chimpanzees show no such preference.

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

Aim and method: A comparison study of four six-year-old children attending a school with a play-based curriculum and a school with a traditionally structured classroom from low socioeconomic areas was conducted in Victoria, Australia. Children’s play, language and social skills were measured in February and again in August. At baseline assessment there was a combined sample of 31 children (mean age 5.5 years, SD 0.35 years; 13 females and 18 males). At follow-up there was a combined sample of 26 children (mean age 5.9 years, SD 0.35 years; 10 females, 16 males). Results: There was no significant difference between the school groups in play, language, social skills, age and sex at baseline assessment. Compared to norms on a standardised assessment, all the children were beginning school with delayed play ability. At follow-up assessment, children at the play-based curriculum school had made significant gains in all areas assessed (p values ranged from 0.000 to 0.05). Children at the school with the traditional structured classroom had made significant positive gains in use of symbols in play (p < 0.05) and semantic language (p < 0.05). At follow-up, there were significant differences between schools in elaborate play (p < 0.000), semantic language (p < 0.000), narrative language (p < 0.01) and social connection (p < 0.01), with children in the play-based curriculum school having significantly higher scores in play, narrative language and language and lower scores in social disconnection. Implications: Children from low SES areas begin school at risk of failure as skills in play, language and social skills are delayed. The school experience increases children’s skills, with children in the play-based curriculum showing significant improvements in all areas assessed. It is argued that a play-based curriculum meets children’s developmental and learning needs more effectively. More research is needed to replicate these results.

Abstract

The aim of this study was to examine the unique contribution of two aspects of emotion regulation (awareness and coping) to the development of internalizing problems in 11-year-old high-functioning children with an autism spectrum disorder (HFASD) and a control group, and the moderating effect of group membership on this. The results revealed overlap between the two groups, but also significant differences, suggesting a more fragmented emotion regulation pattern in children with HFASD, especially related to worry and rumination. Moreover, in children with HFASD, symptoms of depression were unrelated to positive mental coping strategies and the conviction that the emotion experience helps in dealing with the problem, suggesting that a positive approach to the problem and its subsequent emotion experience are less effective in the HFASD group.

Abstract

We present the perspective that interpersonal movement coordination results from establishing interpersonal synergies. Interpersonal synergies are higher-order control systems formed by coupling movement system degrees of freedom of two (or more) actors. Characteristic features of synergies identified in studies of intrapersonal coordination – dimensional compression and reciprocal compensation – are revealed in studies of interpersonal coordination that applied the uncontrolled manifold approach and principal component analysis to interpersonal movement tasks. Broader implications of the interpersonal synergy approach for movement science include an expanded notion of mechanism and an emphasis on interaction-dominant dynamics.

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

The annual conference of the European Second Language Association provides an opportunity for the presentation of second language research with a genuinely European flavour. The theoretical perspectives adopted are wide-ranging and may fall within traditions overlooked elsewhere. Moreover, the studies presented are largely multi-lingual and cross-cultural, as befits the make-up of modern-day Europe. At the same time, the work demonstrates sophisticated awareness of scholarly insights from around the world. The EUROSLA yearbook presents a selection each year of the very best research from the annual conference. Submissions are reviewed and professionally edited, and only those of the highest quality are selected. Contributions are in English.

Abstract

In this study, the influence of plausibility information on the real-time processing of locally ambiguous (“garden path”) sentences in a nonnative language is investigated. Using self-paced reading, we examined how advanced Greek-speaking learners of English and native speaker controls read sentences containing temporary subject–object ambiguities, with the ambiguous noun phrase being either semantically plausible or implausible as the direct object of the immediately preceding verb. Besides providing evidence for incremental interpretation in second language processing, our results indicate that the learners were more strongly influenced by plausibility information than the native speaker controls in their on-line processing of the experimental items. For the second language learners an initially plausible direct object interpretation lead to increased reanalysis difficulty in “weak” garden-path sentences where the required reanalysis did not interrupt the current thematic processing domain. No such evidence of on-line recovery was observed, in contrast, for “strong” garden-path sentences that required more substantial revisions of the representation built thus far, suggesting that comprehension breakdown was more likely here.

Abstract

This paper describes the syntax and semantics of reciprocity in the Central dialect of Rotokas, a non-Austronesian (Papuan) language spoken in Bougainville, Papua New Guinea. In Central Rotokas, there are three main reciprocal construction types, which differ formally according to where the reflexive/reciprocal marker (ora-) occurs in the clause: on the verb, on a pronominal argument or adjunct, or on a body part noun. The choice of construction type is determined by two considerations: the valency of the verb (i.e., whether it has one or two core arguments) and whether the reciprocal action is performed on a body part. The construction types are compatible with a wide range of the logical subtypes of reciprocity (strong, melee, chaining, etc.).

Abstract

Patients with Huntington’s Disease are impaired in the recognition of emotional signals. However, the nature and extent of the impairment is controversial: It has variously been argued to be disgust-specific (Sprengelmeyer et al., 1996; 1997), general for negative emotions (Snowden, et al., 2008), or a consequence of item difficulty (Milders, Crawford, Lamb, & Simpson, 2003). Yet no study to date has included more than one positive stimulus category in emotion recognition tasks. We present a study of 14 Huntington’s patients and 15 control participants performing a forced-choice task with a range of negative and positive non-verbal emotional vocalizations. Participants were found to be impaired in emotion recognition across the emotion categories, including positive emotions such as amusement and sensual pleasure, and negative emotions, such as anger, disgust, and fear. These data complement previous work by demonstrating that impairments are found in the recognition of positive, as well as negative, emotions in Huntington’s disease. Our results point to a global deficit in the recognition of emotional signals in Huntington’s Disease.

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

E. Dhooge and R. J. Hartsuiker (2010) reported experiments showing that picture naming takes longer with low- than high-frequency distractor words, replicating M. Miozzo and A. Caramazza (2003). In addition, they showed that this distractor-frequency effect disappears when distractors are masked or preexposed. These findings were taken to refute models like WEAVER++ (A. Roelofs, 2003) in which words are selected by competition. However, Dhooge and Hartsuiker do not take into account that according to this model, picture-word interference taps not only into word production but also into attentional processes. Here, the authors indicate that WEAVER++ contains an attentional mechanism that accounts for the distractor-frequency effect (A. Roelofs, 2005). Moreover, the authors demonstrate that the model accounts for the influence of masking and preexposure, and does so in a simpler way than the response exclusion through self-monitoring account advanced by Dhooge and Hartsuiker

Abstract

It has been argued that inhibition is a mechanism of attentional control in bilingual language performance. Evidence suggests that effects of inhibition are largest in the tail of a response time (RT) distribution in non-linguistic and monolingual performance domains. We examined this for bilingual performance by conducting delta-plot analyses of naming RTs. Dutch-English bilingual speakers named pictures using English while trying to ignore superimposed neutral Xs or Dutch distractor words that were semantically related, unrelated, or translations. The mean RTs revealed semantic, translation, and lexicality effects. The delta plots leveled off with increasing RT, more so when the mean distractor effect was smaller as compared with larger. This suggests that the influence of inhibition is largest toward the distribution tail, corresponding to what is observed in other performance domains. Moreover, the delta plots suggested that more inhibition was applied by high- than low-proficiency individuals in the unrelated than the other distractor conditions. These results support the view that inhibition is a domain-general mechanism that may be optionally engaged depending on the prevailing circumstances.

Abstract

E. Dhooge and R. J. Hartsuiker (2010) reported experiments showing that picture naming takes longer with low- than high-frequency distractor words, replicating M. Miozzo and A. Caramazza (2003). In addition, they showed that this distractor-frequency effect disappears when distractors are masked or preexposed. These findings were taken to refute models like WEAVER++ (A. Roelofs, 2003) in which words are selected by competition. However, Dhooge and Hartsuiker do not take into account that according to this model, picture-word interference taps not only into word production but also into attentional processes. Here, the authors indicate that WEAVER++ contains an attentional mechanism that accounts for the distractor-frequency effect (A. Roelofs, 2005). Moreover, the authors demonstrate that the model accounts for the influence of masking and preexposure, and does so in a simpler way than the response exclusion through self-monitoring account advanced by Dhooge and Hartsuiker

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

The present work investigated young children’s normative understanding of property rights using a novel methodology. Two- and 3-year-old children participated in situations in which an actor (1) took possession of an object for himself, and (2) attempted to throw it away. What varied was who owned the object: the actor himself, the child subject, or a third party. We found that while both 2- and 3-year-old children protested frequently when their own object was involved, only 3-year-old children protested more when a third party’s object was involved than when the actor was acting on his own object. This suggests that at the latest around 3 years of age young children begin to understand the normative dimensions of property rights.

Abstract

Spoken word recognition is achieved via competition between activated lexical candidates that match the incoming speech input. The competition is modulated by prelexical cues that are important for segmenting the auditory speech stream into linguistic units. One such prelexical cue that listeners rely on in spoken word recognition is phonotactics. Phonotactics defines possible combinations of phonemes within syllables or words in a given language. The present study aimed at investigating both temporal and topographical aspects of the neuronal correlates of phonotactic processing by simultaneously applying event-related brain potentials (ERPs) and functional near-infrared spectroscopy (fNIRS). Pseudowords, either phonotactically legal or illegal with respect to the participants' native language, were acoustically presented to passively listening adult native German speakers. ERPs showed a larger N400 effect for phonotactically legal compared to illegal pseudowords, suggesting stronger lexical activation mechanisms in phonotactically legal material. fNIRS revealed a left hemispheric network including fronto-temporal regions with greater response to phonotactically legal pseudowords than to illegal pseudowords. This confirms earlier hypotheses on a left hemispheric dominance of phonotactic processing most likely due to the fact that phonotactics is related to phonological processing and represents a segmental feature of language comprehension. These segmental linguistic properties of a stimulus are predominantly processed in the left hemisphere. Thus, our study provides first insights into temporal and topographical characteristics of phonotactic processing mechanisms in a passive listening task. Differential brain responses between known and unknown phonotactic rules thus supply evidence for an implicit use of phonotactic cues to guide lexical activation mechanisms.

Abstract

Research has demonstrated that young children quickly acquire knowledge of how the structure of their language encodes meaning. However, this work focused on structurally simple transitives. The present studies investigate childrens' comprehension of the double object dative (e.g., I gave him the box) and the prepositional dative (e.g., I gave the box to him). In Study 1, 3- and 4-year-olds correctly preferred a transfer event reading of prepositional datives with novel verbs (e.g., I'm glorping the rabbit to the duck) but were unable to interpret double object datives (e.g., I'm glorping the duck the rabbit). In Studies 2 and 3, they were able to interpret both dative types when the nouns referring to the theme and recipient were canonically marked (Study 2; I'm glorping the rabbit to Duck) and, to a lesser extent, when they were distinctively but noncanonically marked (Study 3: I'm glorping rabbit to the Duck). Overall, the results suggest that English children have some verb-general knowledge of how dative syntax encodes meaning by 3 years of age, but successful comprehension may require the presence of additional surface cues.

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 a data set of 291 spontaneous utterances from German 5-year-olds, 7-year-olds and adults, nuclear pitch contours were labeled manually using the GToBI annotation system. Ten different contour types were identified. The fundamental frequency (F0) of these contours was modeled using third-order orthogonal polynomials, following an approach similar to the one Grabe, Kochanski, and Coleman (2007) used for English. Statistical analyses showed that all but one contour pair differed significantly from each other in at least one of the four coefficients. This demonstrates that polynomial modeling can provide quantitative empirical support for phonological labels in unscripted speech, and for languages other than English. Furthermore, polynomial expressions can be used to derive the alignment of tonal targets relative to the syllable structure, making polynomial modeling more accessible to the phonological research community. Finally, within-contour comparisons of the three age groups showed that for children, the magnitude of the higher coefficients is lower, suggesting that they are not yet able to modulate their pitch as fast as adults.

Abstract

Background: A well-known test for measuring verbal adequacy (i.e., verbal effectiveness) in mildly impaired aphasic speakers is the Amsterdam-Nijmegen Everyday Language Test (ANELT; Blomert, Koster, & Kean, 1995). Aphasia therapy practitioners score verbal adequacy qualitatively when they administer the ANELT to their aphasic clients in clinical practice. Aims: The current study investigated whether the construct validity of the ANELT could be further improved by substituting the qualitative score by a quantitative one, which takes the number of essential information units into account. The new quantitative measure could have the following advantages: the ability to derive a quantitative score of verbal efficiency, as well as improved sensitivity to detect changes in functional communication over time. Methods & Procedures: The current study systematically compared a new quantitative measure of verbal effectiveness with the current ANELT Comprehensibility scale, which is based on qualitative judgements. A total of 30 speakers of Dutch participated: 20 non-aphasic speakers and 10 aphasic patients with predominantly expressive disturbances. Outcomes & Results: Although our findings need to be replicated in a larger group of aphasic speakers, the main results suggest that the new quantitative measure of verbal effectiveness is more sensitive to detect change in verbal effectiveness over time. What is more, it can be used to derive a measure of verbal efficiency. Conclusions: The fact that both verbal effectiveness and verbal efficiency can be reliably as well as validly measured in the ANELT is of relevance to clinicians. It allows them to obtain a more complete picture of aphasic speakers' functional communication skills.

Abstract

Two cross-linguistic experiments comparing musicians and non-musicians were performed in order to examine whether musicians have enhanced perception of specific acoustical features of speech in a second language (L2). These discrimination and identification experiments examined the perception of various speech features; namely, the timing and quality of Japanese consonants, and the quality of Dutch vowels. We found that musical experience was more strongly associated with discrimination performance rather than identification performance. The enhanced perception was observed not only with respect to L2, but also L1. It was most pronounced when tested with Japanese consonant timing. These findings suggest the following: 1) musicians exhibit enhanced early acoustical analysis of speech, 2) musical training does not equally enhance the perception of all acoustic features automatically, and 3) musicians may enjoy an advantage in the perception of acoustical features that are important in both language and music, such as pitch and timing. Research Highlights We compared the perception of L1 and L2 speech by musicians and non-musicians. Discrimination and identification experiments examined perception of consonant timing, quality of Japanese consonants and of Dutch vowels. We compared results for Japanese native musicians and non-musicians as well as, Dutch native musicians and non-musicians. Musicians demonstrated enhanced perception for both L1 and L2. Most pronounced effect was found for Japanese consonant timing.

Abstract

The current study reports the enhancing effect of a high variability training procedure in the learning of a Japanese geminate-singleton fricative contrast. Dutch natives took part in a five-day training procedure in which they identified geminate and singleton variants of the Japanese fricative /s/. They heard either many repetitions of a limited set of words recorded by a single speaker (simple training) or fewer repetitions of a more variable set of words recorded by multiple speakers (variable training). Pre-post identification evaluations and a transfer test indicated clear benefits of the variable training.

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

Three- and four-year-old children were asked predicate-focus questions ('What's X doing?') about a scene in which an agent performed an action on a patient. We varied: (i) whether (or not) the preceding discourse context, which established the patient as given information, was available for the questioner; and (ii) whether (or not) the patient was perceptually available to the questioner when she asked the question. The main finding in our study differs from those of previous studies since it suggests that children are sensitive to the perceptual context at an earlier age than they are to previous discourse context if they need to take the questioner's perspective into account. Our finding indicates that, while children are in principle sensitive to both factors, young children rely on perceptual availability when a conflict arises.

Abstract

Attention-deficit hyperactivity disorder (ADHD) is a common behavioral disorder affecting about 4–8% of children. ADHD persists into adulthood in around 65% of cases, either as the full condition or in partial remission with persistence of symptoms. Pharmacological, animal and molecular genetic studies support a role for genes of the dopaminergic system in ADHD due to its essential role in motor control, cognition, emotion, and reward. Based on these data, we analyzed two functional polymorphisms within the DRD4 gene (120 bp duplication in the promoter and 48 bp VNTR in exon 3) in a clinical sample of 1,608 adult ADHD patients and 2,352 controls of Caucasian origin from four European countries that had been recruited in the context of the International Multicentre persistent ADHD CollaboraTion (IMpACT). Single-marker analysis of the two polymorphisms did not reveal association with ADHD. In contrast, multiple-marker meta-analysis showed a nominal association (P  = 0.02) of the L-4R haplotype (dup120bp-48bpVNTR) with adulthood ADHD, especially with the combined clinical subtype. Since we previously described association between adulthood ADHD and the dopamine transporter SLC6A3 9R-6R haplotype (3′UTR VNTR-intron 8 VNTR) in the same dataset, we further tested for gene × gene interaction between DRD4 and SLC6A3. However, we detected no epistatic effects but our results rather suggest additive effects of the DRD4 risk haplotype and the SLC6A3 gene.

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.