Publications

Abstract

Human communication is inherently multimodal. Auditory speech, but also visual cues can be used to understand another talker. Most studies of audiovisual speech perception have focused on the perception of speech segments (i.e., speech sounds). However, less is known about the influence of visual information on the perception of suprasegmental aspects of speech like lexical stress. In two experiments, we investigated the influence of different visual cues (e.g., facial articulatory cues and beat gestures) on the audiovisual perception of lexical stress. We presented auditory lexical stress continua of disyllabic Dutch stress pairs together with videos of a speaker producing stress on the first or second syllable (e.g., articulating VOORnaam or voorNAAM). Moreover, we combined and fully crossed the face of the speaker producing lexical stress on either syllable with a gesturing body producing a beat gesture on either the first or second syllable. Results showed that people successfully used visual articulatory cues to stress in muted videos. However, in audiovisual conditions, we were not able to find an effect of visual articulatory cues. In contrast, we found that the temporal alignment of beat gestures with speech robustly influenced participants' perception of lexical stress. These results highlight the importance of considering suprasegmental aspects of language in multimodal contexts.

Abstract

Individual differences in using language are prevalent in our daily lives. Language skills are often assessed in vocational (predominantly written language) and diagnostic contexts. Not much is known, however, about individual differences in spoken language skills. The lack of research is in part due to the lack of suitable test instruments. We introduce the Individual Differences in Language Skills (IDLaS-NL) test battery, a set of 31 behavioural tests that can be used to capture variability in language and relevant general cognitive skills in adult speakers of Dutch. The battery was designed to measure word and sentence production and comprehension skills, linguistic knowledge, nonverbal processing speed, working memory, and nonverbal reasoning. The present article outlines the structure of the battery, describes the materials and procedure of each test, and evaluates the battery’s factor structure based on the results of a sample of 748 Dutch adults, aged between 18 and 30 years, most of them students. The analyses demonstrate that the battery has good construct validity and can be reliably administered both in the lab and via the internet. We therefore recommend the battery as a valuable new tool to assess individual differences in language knowledge and skills; this future work may include linking language skills to other aspects of human cognition and life outcomes.

Abstract

Experimental psychologists and psycholinguists increasingly turn to online research for data collection due to the ease of sampling many diverse participants in parallel. Online research has shown promising validity and consistency, but is it suitable for all paradigms? Specifically, is it reliable enough for individual differences research? The current paper reports performance on 15 tasks from a psycholinguistic individual differences battery, including timed and untimed assessments of linguistic abilities, as well as domain-general skills. From a demographically homogenous sample of young Dutch people, 149 participants participated in the lab study, and 515 participated online. Our results indicate that there is no reason to assume that participants tested online will underperform compared to lab-based testing, though they highlight the importance of motivation and the potential for external help (e.g., through looking up answers) online. Overall, we conclude that there is reason for optimism in the future of online research into individual differences.

Abstract

Speakers sometimes produce lexical errors, such as saying “salt” instead of “pepper.” This study aimed to better understand the origin of lexical errors by assessing whether they arise from a hasty selection and premature decision to speak (premature selection hypothesis) or from momentary attentional disengagement from the task (attentional lapse hypothesis). We analyzed data from a speeded picture naming task (Lampe et al., 2023) and investigated whether lexical errors are produced as fast as target (i.e., correct) responses, thus arising from premature selection, or whether they are produced more slowly than target responses, thus arising from lapses of attention. Using ex-Gaussian analyses, we found that lexical errors were slower than targets in the tail, but not in the normal part of the response time distribution, with the tail effect primarily resulting from errors that were not coordinates, that is, members of the target’s semantic category. Moreover, we compared the coordinate errors and target responses in terms of their word-intrinsic properties and found that they were overall more frequent, shorter, and acquired earlier than targets. Given the present findings, we conclude that coordinate errors occur due to a premature selection but in the context of intact attentional control, following the same lexical constraints as targets, while other errors, given the variability in their nature, may vary in their origin, with one potential source being lapses of attention.

Abstract

Many contemporary texts include shortcuts, such as cu or phones4u. The aim of this study was to investigate how the meanings of shortcuts are retrieved. A primed lexical decision paradigm was used with shortcuts and the corresponding words as primes. The target word was associatively related to the meaning of the whole prime (cu/see you – goodbye), to a component of the prime (cu/see you – look), or unrelated to the prime. In Experiment 1, primes were presented for 57 ms. For both word and shortcut primes, responses were faster to targets preceded by whole-related than by unrelated primes. No priming from component-related primes was found. In Experiment 2, the prime duration was 1000 ms. The priming effect seen in Experiment 1 was replicated. Additionally, there was priming from component-related word primes, but not from component-related shortcut primes. These results indicate that the meanings of shortcuts can be retrieved without translating them first into corresponding words.

Abstract

The human cerebellum plays an important role in language, amongst other cognitive and motor functions [1], but a unifying theoretical framework about cerebellar language function is lacking. In an established model of motor control, the cerebellum is seen as a predictive machine, making short-term estimations about the outcome of motor commands. This allows for flexible control, on-line correction, and coordination of movements [2]. The homogeneous cytoarchitecture of the cerebellar cortex suggests that similar computations occur throughout the structure, operating on different input signals and with different output targets [3]. Several authors have therefore argued that this ‘motor’ model may extend to cerebellar nonmotor functions [3], [4] and [5], and that the cerebellum may support prediction in language processing [6]. However, this hypothesis has never been directly tested. Here, we used the ‘Visual World’ paradigm [7], where on-line processing of spoken sentence content can be assessed by recording the latencies of listeners' eye movements towards objects mentioned. Repetitive transcranial magnetic stimulation (rTMS) was used to disrupt function in the right cerebellum, a region implicated in language [8]. After cerebellar rTMS, listeners showed delayed eye fixations to target objects predicted by sentence content, while there was no effect on eye fixations in sentences without predictable content. The prediction deficit was absent in two control groups. Our findings support the hypothesis that computational operations performed by the cerebellum may support prediction during both motor control and language processing.

Abstract

Earlier studies had shown that speakers naming several objects typically look at each object until they have retrieved the phonological form of its name and therefore look longer at objects with long names than at objects with shorter names. We examined whether this tight eye-to-speech coordination was maintained at different speech rates and after increasing amounts of practice. Participants named the same set of objects with monosyllabic or disyllabic names on up to 20 successive trials. In Experiment 1, they spoke as fast as they could, whereas in Experiment 2 they had to maintain a fixed moderate or faster speech rate. In both experiments, the durations of the gazes to the objects decreased with increasing speech rate, indicating that at higher speech rates, the speakers spent less time planning the object names. The eye-speech lag (the time interval between the shift of gaze away from an object and the onset of its name) was independent of the speech rate but became shorter with increasing practice. Consistent word length effects on the durations of the gazes to the objects and the eye speech lags were only found in Experiment 2. The results indicate that shifts of eye gaze are often linked to the completion of phonological encoding, but that speakers can deviate from this default coordination of eye gaze and speech, for instance when the descriptive task is easy and they aim to speak fast.

Abstract

First paragraph: The topic of the workshop from which this volume comes, “Individual Differences in Second Language Learning,” is timely and important for both practical and theoretical reasons. The practical reasons are obvious: While many people have some knowledge of a second or further language, there is enormous variability in how well they know these languages. Much of this variability is, of course, likely to be due to differences in the time spent studying or being immersed in the language, but even in similar learning environments learners differ greatly in how quickly they pick up a language and in their ultimate level of proficiency.

Abstract

We examined the contribution of executive control to individual differences in response time (RT) for naming objects and actions. Following Miyake, Friedman, Emerson, Witzki, Howerter, and Wager (2000), executive control was assumed to include updating, shifting, and inhibiting abilities, which were assessed using operation-span, task switching, and stop-signal tasks, respectively. Study 1 showed that updating ability was significantly correlated with the mean RT of action naming, but not of object naming. This finding was replicated in Study 2 using a larger stimulus set. Inhibiting ability was significantly correlated with the mean RT of both action and object naming, whereas shifting ability was not correlated with the mean naming RTs. Ex-Gaussian analyses of the RT distributions revealed that updating ability was correlated with the distribution tail of both action and object naming, whereas inhibiting ability was correlated with the leading edge of the distribution for action naming and the tail for object naming. Shifting ability provided no independent contribution. These results indicate that the executive control abilities of updating and inhibiting contribute to the speed of naming objects and actions, although there are differences in the way and extent these abilities are involved.

Abstract

In many tasks the effects of frequency and age of acquisition (AoA) on reaction latencies are similar in size. However, in picture naming the AoA-effect is often significantly larger than expected on the basis of the frequency-effect. Previous explanations of this frequency-independent AoA-effect have attributed it to the organisation of the semantic system or to the way phonological word forms are stored in the mental lexicon. Using a semantic blocking paradigm, we show that semantic context effects on naming latencies are more pronounced for late-acquired than for early-acquired words. This interaction between AoA and naming context is likely to arise during lexical-semantic encoding, which we put forward as the locus for the frequency-independent AoA-effect.

Abstract

In the cyclic semantic blocking paradigm participants repeatedly name sets of objects with semantically related names (homogeneous sets) or unrelated names (heterogeneous sets). The naming latencies are typically longer in related than in unrelated sets. In we replicated this semantic blocking effect and demonstrated that the effect only arose after all objects of a set had been shown and named once. In , the objects of a set were presented simultaneously (instead of on successive trials). Evidence for semantic blocking was found in the naming latencies and in the gaze durations for the objects, which were longer in homogeneous than in heterogeneous sets. For the gaze-to-speech lag between the offset of gaze on an object and the onset of the articulation of its name, a repetition priming effect was obtained but no blocking effect. showed that the blocking effect for speech onset latencies generalized to new, previously unnamed lexical items. We propose that the blocking effect is due to refractory behaviour in the semantic system.

Abstract

Most current theories of lexical access in speech production are designed to capture the behaviour of young adults - typically college students. However, young adults represent a minority of the world's speakers. For theories of speech production, the question arises of how the young adults' speech develops out of the quite different speech observed in children and adolescents and how the speech of young adults evolves into the speech observed in older persons. Though a model of adult speech production need not include a detailed account language development, it should be compatible with current knowledge about the development of language across the lifespan. In this sense, theories of young adults' speech production may be constrained by theories and findings concerning the development of language with age. Conversely, any model of language acquisition or language change in older adults should, of course, be compatible with existing theories of the "ideal" speech found in young speakers. For this SpecialIssue we elicited papers on the development of speech production in childhood, adult speech production, and changes in speech production in older adults. The structure of the Special Issue is roughly chronological, focusing in turn on the language production of children (papers by Behrens; Goffman, Heisler & Chakraborty; Vousden & Maylor), young adults (papers by Roelofs; Schiller, Jansma, Peters & Levelt; Finocchiaro & Caramazza; Hartsuiker & Barkhuysen; Bonin, Malardier, Meot & Fayol) and older adults (papers by Mortensen, Meyer & Humphreys; Spieler & Griffin; Altmann & Kemper). We hope that the work compiled here will encourage researchers in any of these areas to consider the theories and findings in the neighbouring fields.

Abstract

In 3 experiments, the authors investigated the extent to which objects that are about to be named are processed prior to fixation. Participants named pairs or triplets of objects. One of the objects, initially seen extrafoveally (the interloper), was replaced by a different object (the target) during the saccade toward it. The interloper-target pairs were identical or unrelated objects or visually and conceptually unrelated objects with homophonous names (e.g., animal-baseball bat). The mean latencies and gaze durations for the targets were shorter in the identity and homophone conditions than in the unrelated condition. This was true when participants viewed a fixation mark until the interloper appeared and when they fixated on another object and prepared to name it while viewing the interloper. These results imply that objects that are about to be named may undergo far-reaching processing, including access to their names, prior to fixation.