Publications

Abstract

Rhythm and language-related traits are phenotypically correlated, but their genetic overlap is largely unknown. Here, we leveraged two large-scale genome-wide association studies performed to shed light on the shared genetics of rhythm (N=606,825) and dyslexia (N=1,138,870). Our results reveal an intricate shared genetic and neurobiological architecture, and lay groundwork for resolving longstanding debates about the potential co-evolution of human language and musical traits.

Abstract

Humans acquire word knowledge through producing and comprehending spoken and written language. Word learning continues into adulthood and knowledge accumulates across the lifespan. Therefore, receptive vocabulary size is often conceived of as a proxy for linguistic experience and plays a central role in assessing individuals’ language proficiency. There is currently no valid open access test available for assessing receptive vocabulary size in German-speaking adults. We addressed this gap and developed the German Auditory and Image Vocabulary Test (GAudI). In the GAudI, participants are presented with spoken test words and have to indicate their meanings by selecting the corresponding picture from a set of four alternatives. Here we describe the development of the test and provide evidence for its validity. Specifically, we report a study in which 168 German-speaking participants completed the GAudI and five other tests tapping into linguistic experience: one test measuring print exposure, two tests measuring productive vocabulary, one test assessing knowledge of book language grammar, and a test of receptive vocabulary that was normed in adolescents. The psychometric properties of the GAudI and its relationships to the other tests demonstrate that it is a suitable tool for measuring receptive vocabulary size. We offer an open-access digital test environment that can be used for research purposes, accessible via https://ems13.mpi.nl/bq4_customizable_de/researchers_welcome.php.

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

Studies of perception have long shown that the brain adds information to its sensory analysis of the physical environment. A touchstone example for humans is language use: to comprehend a physical signal like speech, the brain must add linguistic knowledge, including syntax. Yet, syntactic rules and representations are widely assumed to be atemporal (i.e., abstract and not bound by time), so they must be translated into time-varying signals for speech comprehension and production. Here, we test 3 different models of the temporal spell-out of syntactic structure against brain activity of people listening to Dutch stories: an integratory bottom-up parser, a predictive top-down parser, and a mildly predictive left-corner parser. These models build exactly the same structure but differ in when syntactic information is added by the brain—this difference is captured in the (temporal distribution of the) complexity metric “incremental node count.” Using temporal response function models with both acoustic and information-theoretic control predictors, node counts were regressed against source-reconstructed delta-band activity acquired with magnetoencephalography. Neural dynamics in left frontal and temporal regions most strongly reflect node counts derived by the top-down method, which postulates syntax early in time, suggesting that predictive structure building is an important component of Dutch sentence comprehension. The absence of strong effects of the left-corner model further suggests that its mildly predictive strategy does not represent Dutch language comprehension well, in contrast to what has been found for English. Understanding when the brain projects its knowledge of syntax onto speech, and whether this is done in language-specific ways, will inform and constrain the development of mechanistic models of syntactic structure building in the brain.

Abstract

When language abilities in aphasia are assessed in clinical and research settings, the standard practice is to examine each language of a multilingual person separately. But many multilingual individuals, with and without aphasia, mix their languages regularly when they communicate with other speakers who share their languages. We applied a novel approach to scoring language production of a multilingual person with aphasia. Our aim was to discover whether the assessment outcome would differ meaningfully when we count accurate responses in only the target language of the assessment session versus when we apply a translanguaging framework, that is, count all accurate responses, regardless of the language in which they were produced. The participant is a Farsi-German-English speaking woman with chronic moderate aphasia. We examined the participant’s performance on two picture-naming tasks, an answering wh-question task, and an elicited narrative task. The results demonstrated that scores in English, the participant’s third-learned and least-impaired language did not differ between the two scoring methods. Performance in German, the participant’s moderately impaired second language benefited from translanguaging-based scoring across the board. In Farsi, her weakest language post-CVA, the participant’s scores were higher under the translanguaging-based scoring approach in some but not all of the tasks. Our findings suggest that whether a translanguaging-based scoring makes a difference in the results obtained depends on relative language abilities and on pragmatic constraints, with additional influence of the linguistic distances between the languages in question.

Abstract

We examined the morphosyntactic prediction ability of child heritage speakers and the role of reading skills and language experience in predictive processing. Using visual world eye-tracking, we focused on predictive use of case-marking cues in Turkish with monolingual (N=49, Mage=83 months) and heritage children, who were early bilinguals of Turkish and Dutch (N=30, Mage=90 months). We found quantitative differences in magnitude of the prediction ability of monolingual and heritage children; however, their overall prediction ability was on par. The heritage speakers’ prediction ability was facilitated by their reading skills in Dutch, but not in Turkish as well as by their heritage language exposure, but not by engagement in literacy activities. These findings emphasize the facilitatory role of reading skills and spoken language experience in predictive processing. This study is the first to show that in a developing bilingual mind, effects of reading-on-prediction can take place across modalities and across languages.

Abstract

Acknowledging that the parent–child attachment is a dyadic relationship, we investigated differences between pairs of parents and preschool children based on gender configurations in the association between attachment and problem behavior. We looked at mother–daughter, mother–son, father–daughter, and father–son dyads, but also compared mothers and fathers, daughters and sons, and same versus different gender pairs. We employed multigroup structural equation modeling to explore moderation effects of gender in a sample of 446 independent pairs of parents and preschool children (2–5 years old) from the Netherlands. A stronger association between both secure and avoidant attachment and internalizing problems was found for father–son dyads compared to father–daughter dyads. A stronger association between both secure and avoidant attachment and externalizing problems was found for mother–son dyads compared to mother–daughter and father–daughter dyads. Sons showed a stronger negative association between secure attachment and externalizing problems, a stronger positive association between avoidant attachment and externalizing problems, and a stronger negative association between secure attachment and internalizing problems compared to daughters. These results provide evidence for gender moderation and demonstrate that a dyadic approach can reveal patterns of associations that would not be recognized if parent and child gender effects were assessed separately.

Abstract

*All authors contributed equally to this work
Meaningful gestures enhance degraded speech comprehension in neurotypical adults, but it is unknown whether this is the case for neurodivergent populations, such as autistic individuals. Previous research demonstrated atypical multisensory and speech-gesture integration in autistic individuals, suggesting that integrating speech and gestures may be more challenging and less beneficial for speech comprehension in adverse listening conditions in comparison to neurotypicals. Conversely, autistic individuals could also benefit from additional cues to comprehend speech in noise, as they encounter difficulties in filtering relevant information from noise. We here investigated whether gestural enhancement of degraded speech comprehension differs for neurotypical (n = 40, mean age = 24.1) compared to autistic (n = 40, mean age = 26.8) adults. Participants watched videos of an actress uttering a Dutch action verb in clear or degraded speech accompanied with or without a gesture, and completed a free-recall task. Gestural enhancement was observed for both autistic and neurotypical individuals, and did not differ between groups. In contrast to previous literature, our results demonstrate that autistic individuals do benefit from gestures during degraded speech comprehension, similar to neurotypicals. These findings provide relevant insights to improve communication practices with autistic individuals and to develop new interventions for speech comprehension.

Abstract

Speech is often accompanied by gestures. Since beat gestures—simple nonreferential up-and-down hand movements—frequently co-occur with prosodic prominence, they can indicate stress in a word and hence influence spoken-word recognition. However, little is known about the reverse influence of auditory speech on visual perception. The current study investigated whether lexical stress has an effect on the perceived timing of hand beats. We used videos in which a disyllabic word, embedded in a carrier sentence (Experiment 1) or in isolation (Experiment 2), was coupled with an up-and-down hand beat, while varying their degrees of asynchrony. Results from Experiment 1, a novel beat timing estimation task, revealed that gestures were estimated to occur closer in time to the pitch peak in a stressed syllable than their actual timing, hence reducing the perceived temporal distance between gestures and stress by around 60%. Using a forced-choice task, Experiment 2 further demonstrated that listeners tended to perceive a gesture, falling midway between two syllables, on the syllable receiving stronger cues to stress than the other, and this auditory effect was greater when gestural timing was most ambiguous. Our findings suggest that f0 and intensity are the driving force behind the temporal attraction effect of stress on perceived gestural timing. This study provides new evidence for auditory influences on visual perception, supporting bidirectionality in audiovisual interaction between speech-related signals that occur in everyday face-to-face communication.

Abstract

Background

The factors that contribute to language alternation by bilingual speakers with aphasia have been debated. Some studies suggest that atypical language mixing results from impairments in language control, while others posit that mixing is a way to enhance communicative effectiveness. To address this question, most prior research examined the appropriateness of language mixing in connected speech tasks.
Aims

The goal of this study was to provide new insight into the question whether language mixing in aphasia reflects a strategy to enhance verbal effectiveness or involuntary behaviour resulting from impaired language control.
Methods & procedures

Semi-structured web-based interviews with bilingual speakers with aphasia (N = 19) with varying language backgrounds were conducted. The interviews were transcribed and coded for: (1) Self-reports regarding language control and compensation, (2) instances of language mixing, and (3) in two cases, instances of repair initiation.
Outcomes & results

The results showed that several participants reported language control difficulties but that the knowledge of additional languages could also be recruited to compensate for lexical retrieval problems. Most participants showed no or very few instances of mixing and the observed mixes appeared to adhere to the pragmatic context and known functions of switching. Three participants exhibited more marked switching behaviour and reported corresponding difficulties with language control. Instances of atypical mixing did not coincide with clear problems initiating conversational repair.
Conclusions

Our study highlights the variability in language mixing patterns of bilingual speakers with aphasia. Furthermore, most of the individuals in the study appeared to be able to effectively control their languages, and to alternate between their languages for compensatory purposes. Control deficits resulting in atypical language mixing were observed in a small number of participants.

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

When talking, speakers naturally produce hand movements (co-speech gestures) that contribute to communication. Evidence in Dutch suggests that the timing of simple up-and-down, non-referential “beat” gestures influences spoken word recognition: the same auditory stimulus was perceived as CONtent (noun, capitalized letters indicate stressed syllables) when a beat gesture occurred on the first syllable, but as conTENT (adjective) when the gesture occurred on the second syllable. However, these findings were based on a small number of minimal pairs in Dutch, limiting the generalizability of the findings. We therefore tested this effect in Spanish, where lexical stress is highly relevant in the verb conjugation system, distinguishing bailo, “I dance” with word-initial stress from bailó, “she danced” with word-final stress. Testing a larger sample (N = 100), we also assessed whether individual differences in working memory capacity modulated how much individuals relied on the gestures in spoken word recognition. The results showed that, similar to Dutch, Spanish participants were biased to perceive lexical stress on the syllable that visually co-occurred with a beat gesture, with the effect being strongest when the acoustic stress cues were most ambiguous. No evidence was found for by-participant effect sizes to be influenced by individual differences in phonological or visuospatial working memory. These findings reveal gestural-speech coordination impacts lexical stress perception in a language where listeners are regularly confronted with such lexical stress contrasts, highlighting the impact of gestures’ timing on prominence perception and spoken word recognition.

Abstract

We argue that language learning occurs in triadic interactions, where caregivers and children engage not only with each other but also with objects, actions and non-verbal cues that shape language acquisition. We illustrate this using two studies on real-time interactions in spoken and signed language. The first examines shared book reading, showing how caregivers use speech, gestures and gaze coordination to establish joint attention, facilitating word-object associations. The second study explores joint attention in spoken and signed interactions, demonstrating that signing dyads rely on a wider range of multimodal behaviours – such as touch, vibrations and peripheral gaze – compared to speaking dyads. Our data highlight how different language modalities shape attentional strategies. We advocate for research that fully incorporates the dynamic interplay between language, attention and environment.

Abstract

In face-to-face conversation, people use speech and gesture to convey meaning. Seeing gestures alongside speech facilitates comprehenders’ language processing, but crucially, the mechanisms underlying this facilitation remain unclear. We investigated whether comprehenders use the semantic information in gestures, typically preceding related speech, to predict upcoming meaning. Dutch adults listened to questions asked by a virtual avatar. Questions were accompanied by an iconic gesture (e.g., typing) or meaningless control movement (e.g., arm scratch) followed by a short pause and target word (e.g., “type”). A Cloze experiment showed that gestures improved explicit predictions of upcoming target words. Moreover, an EEG experiment showed that gestures reduced alpha and beta power during the pause, indicating anticipation, and reduced N400 amplitudes, demonstrating facilitated semantic processing. Thus, comprehenders use iconic gestures to predict upcoming meaning. Theories of linguistic prediction should incorporate communicative bodily signals as predictive cues to capture how language is processed in face-to-face interaction.

Abstract

Do aesthetic preferences for images of neatly organized compositions (e.g., images collected on blogs like Things Organized Neatly©) generalize across cultures? In an earlier study, focusing on stimulus and personal properties related to order and complexity, Western participants indicated their preference for one of two simultaneously presented images (100 pairs). In the current study, we compared the data of the native Dutch-speaking participants from this earlier sample (N = 356) to newly collected data from a native Chinese-speaking sample (N = 220). Overall, aesthetic preferences were quite similar across cultures. When relating preferences for each sample to ratings of order, complexity, soothingness, and fascination collected from a Western, mainly Dutch-speaking sample, the results hint at a cross-culturally consistent preference for images that Western participants rate as more ordered, but a cross-culturally diverse relation between preferences and complexity.

Abstract

When we communicate with others, we often repeat aspects of each other's communicative behavior such as sentence structures and words. Such behavioral alignment has been mostly studied for speech or text. Yet, language use is mostly multimodal, flexibly using speech and gestures to convey messages. Here, we explore the use of alignment in speech (words) and co-speech gestures (iconic gestures) in a referential communication task aimed at finding labels for novel objects in interaction. In particular, we investigate how people flexibly use lexical and gestural alignment to create shared labels for novel objects and whether alignment in speech and gesture are related over time. The present study shows that interlocutors establish shared labels multimodally, and alignment in words and iconic gestures are used throughout the interaction. We also show that the amount of lexical alignment positively associates with the amount of gestural alignment over time, suggesting a close relationship between alignment in the vocal and manual modalities.

Abstract

Comparative neurobiology allows us to investigate relationships between phylogeny and the brain and understand the evolution of traits. Bats constitute an attractive group of mammalian species for comparative studies, given their large diversity in behavioural phenotypes, brain morphology, and array of specialised traits. Currently, the order Chiroptera contains over 1,450 species within 21 families and spans ca. 65 million years of evolution. To date, 194 Neotropical bat species (ca. 13% of the total number of species around the world) have been recorded in Central America. This study includes qualitative and quantitative macromorphological descriptions of the brains of 12 species from six families of Neotropical bats. These analyses, which include histological neuronal staining of two species from different families (Phyllostomus hastatus and Saccopteryx bilineata), show substantial diversity in brain macromorphology including brain shape and size, exposure of mesencephalic regions, and cortical and cerebellar fissure depth. Brain macromorphology can in part be explained by phylogeny as species within the same family are more similar to each other. However, macromorphology cannot be explained by evolutionary time alone as brain differences between some phyllostomid bats are larger than between species from the family Emballonuridae despite being of comparable diverging distances in the phylogenetic tree. This suggests that faster evolutionary changes in brain morphology occurred in phyllostomids — although a larger number of species needs to be studied to confirm this. Our results show the rich diversity in brain morphology that bats provide for comparative and evolutionary studies.

Abstract

We present a reference genome assembly from an individual male Rhynchonycteris naso (Chordata; Mammalia; Chiroptera; Emballonuridae). The genome sequence is 2.46 Gb in span. The majority of the assembly is scaffolded into 22 chromosomal pseudomolecules, with the Y sex chromosome assembled.

Abstract

Language is supported by a distributed network of brain regions with a particular contribution from the left hemisphere. A multi-level understanding of this network requires studying the genetic architecture of its functional connectivity and hemispheric asymmetry. We used resting state functional imaging data from 29,681 participants from the UK Biobank to measure functional connectivity between 18 left-hemisphere regions implicated in multimodal sentence-level processing, as well as their homotopic regions in the right-hemisphere, and interhemispheric connections. Multivariate genome-wide association analysis of this total network, based on common genetic variants (with population frequencies above 1%), identified 14 loci associated with network functional connectivity. Three of these loci were also associated with hemispheric differences of intrahemispheric connectivity. Polygenic dispositions to lower language-related abilities, dyslexia and left-handedness were associated with generally reduced leftward asymmetry of functional connectivity, but with some trait- and connection-specific exceptions. Exome-wide association analysis based on rare, protein-altering variants (frequencies < 1%) suggested 7 additional genes. These findings shed new light on the genetic contributions to language network connectivity and its asymmetry based on both common and rare genetic variants, and reveal genetic links to language-related traits and hemispheric dominance for hand preference.

Abstract

The observation that the neural correlates of reading are left-lateralized is ubiquitous in the cognitive neuroscience and neuropsychological literature. Still, reading is served by a constellation of neural units, and the extent to which these units are consistently left-lateralized is unclear. In this regard, the functional lateralization of the fusiform gyrus is of particular interest, by virtue of its hypothesized role as a “visual word form area”. A quantitative Activation Likelihood Estimation meta-analysis was conducted on activation foci from 35 experiments investigating silent reading, and both a whole-brain and a bayesian ROI-based approach were used to assess the lateralization of the data submitted to meta-analysis. Perirolandic areas showed the highest level of left-lateralization, the fusiform cortex and the parietal cortex exhibited only a moderate pattern of left-lateralization, while in the occipital, insular cortices and in the cerebellum the lateralization turned out to be the lowest observed. The relatively limited functional lateralization of the fusiform gyrus was further explored in a regression analysis on the lateralization profile of each study. The functional lateralization of the fusiform gyrus during reading was positively associated with the lateralization of the precentral and inferior occipital gyri and negatively associated with the lateralization of the triangular portion of the inferior frontal gyrus and of the temporal pole. Overall, the present data highlight how lateralization patterns differ within the reading network. Furthermore, the present data highlight how the functional lateralization of the fusiform gyrus during reading is related to the degree of functional lateralization of other language brain areas.

Abstract

While infants' sensitivity to visual speech cues and the benefit of these cues have been well-established by behavioural studies, there is little evidence on the effect of visual speech cues on infants' neural processing of continuous auditory speech. In this study, we investigated whether visual speech cues, such as the movements of the lips, jaw, and larynx, facilitate infants' neural speech tracking. Ten-month-old Dutch-learning infants watched videos of a speaker reciting passages in infant-directed speech while electroencephalography (EEG) was recorded. In the videos, either the full face of the speaker was displayed or the speaker's mouth and jaw were masked with a block, obstructing the visual speech cues. To assess neural tracking, speech-brain coherence (SBC) was calculated, focusing particularly on the stress and syllabic rates (1–1.75 and 2.5–3.5 Hz respectively in our stimuli). First, overall, SBC was compared to surrogate data, and then, differences in SBC in the two conditions were tested at the frequencies of interest. Our results indicated that infants show significant tracking at both stress and syllabic rates. However, no differences were identified between the two conditions, meaning that infants' neural tracking was not modulated further by the presence of visual speech cues. Furthermore, we demonstrated that infants' neural tracking of low-frequency information is related to their subsequent vocabulary development at 18 months. Overall, this study provides evidence that infants' neural tracking of speech is not necessarily impaired when visual speech cues are not fully visible and that neural tracking may be a potential mechanism in successful language acquisition.

Abstract

The environment in which infants learn language is multimodal and rich with social cues. Yet, the effects of such cues, such as eye contact, on early speech perception have not been closely examined. This study assessed the role of ostensive speech, signalled through the speaker's eye gaze direction, on infants’ word segmentation abilities. A familiarisation-then-test paradigm was used while electroencephalography (EEG) was recorded. Ten-month-old Dutch-learning infants were familiarised with audio-visual stories in which a speaker recited four sentences with one repeated target word. The speaker addressed them either with direct or with averted gaze while speaking. In the test phase following each story, infants heard familiar and novel words presented via audio-only. Infants’ familiarity with the words was assessed using event-related potentials (ERPs). As predicted, infants showed a negative-going ERP familiarity effect to the isolated familiarised words relative to the novel words over the left-frontal region of interest during the test phase. While the word familiarity effect did not differ as a function of the speaker's gaze over the left-frontal region of interest, there was also a (not predicted) positive-going early ERP familiarity effect over right fronto-central and central electrodes in the direct gaze condition only. This study provides electrophysiological evidence that infants can segment words from audio-visual speech, regardless of the ostensiveness of the speaker's communication. However, the speaker's gaze direction seems to influence the processing of familiar words.

Abstract

Human language offers a variety of ways to create meaning, one of which is referring to entities, objects, or events in the world. One such meaning maker is understanding to whom or to what a pronoun in a discourse refers to. To understand a pronoun, the brain must access matching entities or concepts that have been encoded in memory from previous linguistic context. Models of language processing propose that internally stored linguistic concepts, accessed via exogenous cues such as phonological input of a word, are represented as (a)synchronous activities across a population of neurons active at specific frequency bands. Converging evidence suggests that delta band activity (1–3 Hz) is involved in temporal and representational integration during sentence processing. Moreover, recent advances in the neurobiology of memory suggest that recollection engages neural dynamics similar to those which occurred during memory encoding. Integrating from these two research lines, we here tested the hypothesis that neural dynamic patterns, especially in delta frequency range, underlying referential meaning representation, would be reinstated during pronoun resolution. By leveraging neural decoding techniques (i.e., representational similarity analysis) on a magnetoencephalogram data set acquired during a naturalistic story-listening task, we provide evidence that delta-band activity underlies referential meaning representation. Our findings suggest that, during spoken language comprehension, endogenous linguistic representations such as referential concepts may be proactively retrieved and represented via activation of their underlying dynamic neural patterns.

Abstract

Harbor seals (Phoca vitulina) are more solitary than many other pinnipeds. Yet, they are capable of vocal learning, a form of social learning. Most extant literature examines social animals when investigating social learning, despite sociality not being a prerequisite. Here, we report two formerly silent harbor seals who initiated vocalizations, after having repeatedly observed a conspecific receiving food rewards for vocalizing. Our observations suggest both social and vocal learning in a group of captive harbor seals, a species that lives semi-solitarily in the wild. We propose that, in this case, social learning acted as a shortcut to acquiring food rewards compared to the comparatively costly asocial learning.

Abstract

Background

Which mammals show vocal learning abilities, e.g., can learn new sounds, or learn to use sounds in new contexts? Vocal usage and comprehension learning are submodules of vocal learning. Specifically, vocal usage learning is the ability to learn to use a vocalization in a new context; vocal comprehension learning is the ability to comprehend a vocalization in a new context. Among mammals, harbor seals (Phoca vitulina) are good candidates to investigate vocal learning. Here, we test whether harbor seals are capable of vocal usage and comprehension learning.

Results

We trained two harbor seals to (i) switch contexts from a visual to an auditory cue. In particular, the seals first produced two vocalization types in response to two hand signs; they then transitioned to producing these two vocalization types upon the presentation of two distinct sets of playbacks of their own vocalizations. We then (ii) exposed the seals to a combination of trained and novel vocalization stimuli. In a final experiment, (iii) we broadcasted only novel vocalizations of the two vocalization types to test whether seals could generalize from the trained set of stimuli to only novel items of a given vocal category. Both seals learned all tasks and took ≤ 16 sessions to succeed across all experiments. In particular, the seals showed contextual learning through switching the context from former visual to novel auditory cues, vocal matching and generalization. Finally, by responding to the played-back vocalizations with distinct vocalizations, the animals showed vocal comprehension learning.

Conclusions

It has been suggested that harbor seals are vocal learners; however, to date, these observations had not been confirmed in controlled experiments. Here, through three experiments, we could show that harbor seals are capable of both vocal usage and comprehension learning.

Abstract

Although there is a large body of research assessing whether exposure to narratives boosts social cognition immediately afterward, not much research has investigated the underlying mechanism of this putative effect. This experiment investigates the possibility that reading a narrative increases social curiosity directly afterward, which might explain the short-term boosts in social cognition reported by some others. We developed a novel measure of state social curiosity and collected data from participants (N = 222) who were randomly assigned to read an excerpt of narrative fiction or expository nonfiction. Contrary to our expectations, we found that those who read a narrative exhibited less social curiosity afterward than those who read an expository text. This result was not moderated by trait social curiosity. An exploratory analysis uncovered that the degree to which texts present readers with social targets predicted less social curiosity. Our experiment demonstrates that reading narratives, or possibly texts with social content in general, may engage and fatigue social-cognitive abilities, causing a temporary decrease in social curiosity. Such texts might also temporarily satisfy the need for social connection, temporarily reducing social curiosity. Both accounts are in line with theories describing how narratives result in better social cognition over the long term.

Abstract

Earlier work has explored spoken word production during irrelevant background speech such as intelligible and unintelligible word lists. The present study compared how different types of irrelevant background speech (word lists vs. sentences) influenced spoken word production relative to a quiet control condition, and whether the influence depended on the intelligibility of the background speech. Experiment 1 presented native Dutch speakers with Chinese word lists and sentences. Experiment 2 presented a similar group with Dutch word lists and sentences. In both experiments, the lexical selection demands in speech production were manipulated by varying name agreement (high vs. low) of the to-be-named pictures. Results showed that background speech, regardless of its intelligibility, disrupted spoken word production relative to a quiet condition, but no effects of word lists versus sentences in either language were found. Moreover, the disruption by intelligible background speech compared with the quiet condition was eliminated when planning low name agreement pictures. These findings suggest that any speech, even unintelligible speech, interferes with production, which implies that the disruption of spoken word production is mainly phonological in nature. The disruption by intelligible background speech can be reduced or eliminated via top–down attentional engagement.

Abstract

* Ole Goltermann and Gökberk Alagöz contributed equally.
Primate brain evolution has involved prominent expansions of the cerebral cortex, with largest effects observed in the human lineage. Such expansions were accompanied by fine-grained anatomical alterations, including increased cortical folding. However, the molecular bases of evolutionary alterations in human sulcal organization are not yet well understood. Here, we integrated data from recently completed large-scale neuroimaging genetic analyses with annotations of the human genome relevant to various periods and events in our evolutionary history. These analyses identified single-nucleotide polymorphism (SNP) heritability enrichments in fetal brain human-gained enhancer (HGE) elements for a number of sulcal structures, including the central sulcus, which is implicated in human hand dexterity. We zeroed in on a genomic region that harbors DNA variants associated with left central sulcus shape, an HGE element, and genetic loci involved in neurogenesis including ZIC4, to illustrate the value of this approach for probing the complex factors contributing to human sulcal evolution.

Abstract

Formants, or resonance frequencies of the upper vocal tract, are an essential part of acoustic communication. Articulatory gestures—such as jaw, tongue, lip, and soft palate movements—shape formant structure in human vocalizations, but little is known about how nonhuman mammals use those gestures to modify formant frequencies. Here, we report a case study with an adult male harbor seal trained to produce an arbitrary vocalization composed of multiple repetitions of the sound wa. We analyzed jaw movements frame-by-frame and matched them to the tracked formant modulation in the corresponding vocalizations. We found that the jaw opening angle was strongly correlated with the first (F1) and, to a lesser degree, with the second formant (F2). F2 variation was better explained by the jaw angle opening when the seal was lying on his back rather than on the belly, which might derive from soft tissue displacement due to gravity. These results show that harbor seals share some common articulatory traits with humans, where the F1 depends more on the jaw position than F2. We propose further in vivo investigations of seals to further test the role of the tongue on formant modulation in mammalian sound production.

Abstract

Common genetic variation has been associated with multiple symptoms in Autism Spectrum Disorder (ASD). However, our knowledge of shared genetic factor structures contributing to this highly heterogeneous neurodevelopmental condition is limited. Here, we developed a structural equation modelling framework to directly model genome-wide covariance across core and non-core ASD phenotypes, studying autistic individuals of European descent using a case-only design. We identified three independent genetic factors most strongly linked to language/cognition, behaviour and motor development, respectively, when studying a population-representative sample (N=5,331). These analyses revealed novel associations. For example, developmental delay in acquiring personal-social skills was inversely related to language, while developmental motor delay was linked to self-injurious behaviour. We largely confirmed the three-factorial structure in independent ASD-simplex families (N=1,946), but uncovered simplex-specific genetic overlap between behaviour and language phenotypes. Thus, the common genetic architecture in ASD is multi-dimensional and contributes, in combination with ascertainment-specific patterns, to phenotypic heterogeneity.

Abstract

To understand the neurocognitive mechanisms that underlie heterogeneity in cognitive ageing, recent scientific efforts have led to a growing public availability of imaging cohort data. The Advanced BRain Imaging on ageing and Memory (ABRIM) project aims to add to these existing datasets by taking an adult lifespan approach to provide a cross-sectional, normative database with a particular focus on connectivity, myelinization and iron content of the brain in concurrence with cognitive functioning, mechanisms of reserve, and sleep-wake rhythms. ABRIM freely shares MRI and behavioural data from 295 participants between 18–80 years, stratified by age decade and sex (median age 52, IQR 36–66, 53.20% females). The ABRIM MRI collection consists of both the raw and pre-processed structural and functional MRI data to facilitate data usage among both expert and non-expert users. The ABRIM behavioural collection includes measures of cognitive functioning (i.e., global cognition, processing speed, executive functions, and memory), proxy measures of cognitive reserve (e.g., educational attainment, verbal intelligence, and occupational complexity), and various self-reported questionnaires (e.g., on depressive symptoms, pain, and the use of memory strategies in daily life and during a memory task). In a sub-sample (n = 120), we recorded sleep-wake rhythms using an actigraphy device (Actiwatch 2, Philips Respironics) for a period of 7 consecutive days. Here, we provide an in-depth description of our study protocol, pre-processing pipelines, and data availability. ABRIM provides a cross-sectional database on healthy participants throughout the adult lifespan, including numerous parameters relevant to improve our understanding of cognitive ageing. Therefore, ABRIM enables researchers to model the advanced imaging parameters and cognitive topologies as a function of age, identify the normal range of values of such parameters, and to further investigate the diverse mechanisms of reserve and resilience.

Abstract

We investigated prediction skills of adult heritage speakers and the role of written and spoken language experience on predictive processing. Using visual world eye-tracking, we focused on predictive use of case-marking cues in verb-medial and verb-final sentences in Turkish with adult Turkish heritage speakers (N = 25) and Turkish monolingual speakers (N = 24). Heritage speakers predicted in verb-medial sentences (when verb-semantic and case-marking cues were available), but not in verb-final sentences (when only case-marking cues were available) while monolinguals predicted in both. Prediction skills of heritage speakers were modulated by their spoken language experience in Turkish and written language experience in both languages. Overall, these results strongly suggest that verb-semantic information is needed to scaffold the use of morphosyntactic cues for prediction in heritage speakers. The findings also support the notion that both spoken and written language experience play an important role in predictive spoken language processing.

Abstract

Expressing Left-Right relations is challenging for speaking-children. Yet, this challenge was absent for signing-children, possibly due to iconicity in the visual-spatial modality of expression. We investigate whether there is also a modality advantage when speaking-children’s co-speech gestures are considered. Eight-year-old child and adult hearing monolingual Turkish speakers and deaf signers of Turkish-Sign-Language described pictures of objects in various spatial relations. Descriptions were coded for informativeness in speech, sign, and speech-gesture combinations for encoding Left-Right relations. The use of co-speech gestures increased the informativeness of speakers’ spatial expressions compared to speech-only. This pattern was more prominent for children than adults. However, signing-adults and children were more informative than child and adult speakers even when co-speech gestures were considered. Thus, both speaking- and signing-children benefit from iconic expressions in visual modality. Finally, in each modality, children were less informative than adults, pointing to the challenge of this spatial domain in development.

Abstract

Multimodal rhythmic signalling abounds across animal taxa. Studying its mechanisms and functions can highlight adaptive components in highly complex rhythmic behaviours, like dance and music. Pinnipeds, such as the harbour seal, Phoca vitulina, are excellent comparative models to assess rhythmic capacities. Harbour seals engage in rhythmic percussive behaviours which, until now, have not been described in detail. In our study, eight zoo-housed harbour seals (two pups, two juveniles and four adults) were passively monitored by audio and video during their pupping/breeding season. All juvenile and adult animals performed percussive signalling with their fore flippers in agonistic conditions, both on land and in water. Flipper slap sequences produced on the ground or on the seals' bodies were often highly regular in their interval duration, that is, were quasi-isochronous, at a 200–600 beats/min pace. Three animals also showed significant lateralization in slapping. In contrast to slapping on land, display slapping in water, performed only by adult males, showed slower tempo by one order of magnitude, and a rather motivic temporal structure. Our work highlights that percussive communication is a significant part of harbour seals' behavioural repertoire. We hypothesize that its forms of rhythm production may reflect adaptive functions such as regulating internal states and advertising individual traits.

Abstract

We examined the extent to which cognate facilitation effects occurred in simultaneous bilingual children’s production and comprehension and how these were modulated by language dominance and language context. Bilingual Dutch-German children, ranging from Dutch-dominant to German-dominant, performed picture naming and auditory lexical decision tasks in single-language and dual-language contexts. Language context was manipulated with respect to the language of communication (with the experimenter and in instructional videos) and by means of proficiency tasks. Cognate facilitation effects emerged in both production and comprehension and interacted with both dominance and context. In a single-language context, stronger cognate facilitation effects were found for picture naming in children’s less dominant language, in line with previous studies on individual differences in lexical activation. In the dual-language context, this pattern was reversed, suggesting inhibition of the dominant language at the decision level. Similar effects were observed in lexical decision. These findings provide evidence for an integrated bilingual lexicon in simultaneous bilingual children and shed more light on the complex interplay between lexicon-internal and lexicon-external factors modulating the extent of lexical cross-linguistic influence more generally.

Abstract

In a between-language lexical priming study, we examined to what extent the two languages in a simultaneous bilingual child's lexicon interact, while taking individual differences in language exposure into account. Primary-school-aged Dutch–Greek bilinguals performed a primed picture selection task combined with eye-tracking. They matched pictures to auditorily presented Dutch target words preceded by Greek prime words. Their reaction times and eye movements were recorded. We tested for effects of between-language phonological priming, translation priming, and phonological priming through translation. Priming effects emerged in reaction times and eye movements in all three conditions, at different stages of processing, and unaffected by language exposure. These results extend previous findings for bilingual toddlers and bilingual adults. Processing similarities between these populations indicate that, across different stages of development, bilinguals have an integrated lexicon that is accessed in a language-nonselective way and is susceptible to interactions within and between different types of lexical representation.

Abstract

Classical galactosaemia (CG) is a hereditary disease in galactose metabolism that despite dietary treatment is characterized by a wide range of cognitive deficits, among which is language production. CG brain functioning has been studied with several neuroimaging techniques, which revealed both structural and functional atypicalities. In the present study, for the first time, we compared the oscillatory dynamics, especially the power spectrum and time–frequency representations (TFR), in the electroencephalography (EEG) of CG patients and healthy controls while they were performing a language production task. Twenty-one CG patients and 19 healthy controls described animated scenes, either in full sentences or in words, indicating two levels of complexity in syntactic planning. Based on previous work on the P300 event related potential (ERP) and its relation with theta frequency, we hypothesized that the oscillatory activity of patients and controls would differ in theta power and TFR. With regard to behavior, reaction times showed that patients are slower, reflecting the language deficit. In the power spectrum, we observed significant higher power in patients in delta (1–3 Hz), theta (4–7 Hz), beta (15–30 Hz) and gamma (30–70 Hz) frequencies, but not in alpha (8–12 Hz), suggesting an atypical oscillatory profile. The time-frequency analysis revealed significantly weaker event-related theta synchronization (ERS) and alpha desynchronization (ERD) in patients in the sentence condition. The data support the hypothesis that CG language difficulties relate to theta–alpha brain oscillations.

Abstract

Anecdotal evidence suggests that learning a new foreign language (FL) makes you forget previously learned FLs. To seek empirical evidence for this claim, we tested whether learning words in a previously unknown L3 hampers subsequent retrieval of their L2 translation equivalents. In two experiments, Dutch native speakers with knowledge of English (L2), but not Spanish (L3), first completed an English vocabulary test, based on which 46 participant-specific, known English words were chosen. Half of those were then learned in Spanish. Finally, participants’ memory for all 46 English words was probed again in a picture naming task. In Experiment 1, all tests took place within one session. In Experiment 2, we separated the English pre-test from Spanish learning by a day and manipulated the timing of the English post-test (immediately after learning vs. 1 day later). By separating the post-test from Spanish learning, we asked whether consolidation of the new Spanish words would increase their interference strength. We found significant main effects of interference in naming latencies and accuracy: Participants speeded up less and were less accurate to recall words in English for which they had learned Spanish translations, compared with words for which they had not. Consolidation time did not significantly affect these interference effects. Thus, learning a new language indeed comes at the cost of subsequent retrieval ability in other FLs. Such interference effects set in immediately after learning and do not need time to emerge, even when the other FL has been known for a long time.

Abstract

Background

Forced switching between languages poses demands on control abilities, which may be difficult to meet for bilinguals with aphasia. Freely choosing languages has been shown to increase naming efficiency in healthy bilinguals, and lexical accessibility was found to be a predictor for language choice. The overlap between bilingual language switching and other types of switching is yet unclear.

Aims

This study aimed to examine the benefits of free language choice for bilinguals with aphasia and to investigate the overlap of between- and within-language switching abilities.

Methods & Procedures

Seventeen bilinguals with aphasia completed a questionnaire and four web-based picture naming tasks: single-language naming in the first and second language separately; voluntary switching between languages; cued and predictable switching between languages; cued and predictable switching between phrase types in the first language. Accuracy and naming latencies were analysed using (generalised) linear mixed-effects models.

Outcomes & Results

The results showed higher accuracy and faster naming for the voluntary switching condition compared to single-language naming and cued switching. Both voluntary and cued language switching yielded switch costs, and voluntary switch costs were larger. Ease of lexical access was a reliable predictor for voluntary language choice. We obtained no statistical evidence for differences or associations between switch costs in between- and within-language switching.

Conclusions

Several results point to benefits of voluntary language switching for bilinguals with aphasia. Freely mixing languages improved naming accuracy and speed, and ease of lexical access affected language choice. There was no statistical evidence for overlap of between- and within-language switching abilities. This study highlights the benefits of free language choice for bilinguals with aphasia.

Abstract

Previous research examining the factors that determine language choice and voluntary switching mainly involved early bilinguals. Here, using picture naming, we investigated language choice and switching in late Dutch–English bilinguals. We found that naming was overall slower in cued than in voluntary switching, but switch costs occurred in both types of switching. The magnitude of switch costs differed depending on the task and language, and was moderated by L2 proficiency. Self-rated rather than objectively assessed proficiency predicted voluntary switching and ease of lexical access was associated with language choice. Between-language and within-language switch costs were not correlated. These results highlight self-rated proficiency as a reliable predictor of voluntary switching, with language modulating switch costs. As in early bilinguals, ease of lexical access was related to word-level language choice of late bilinguals.

Abstract

* These two authors contributed equally to this study
Statistical learning – the ability to extract distributional regularities from input – is suggested to be key to language acquisition. Yet, evidence for the human capacity for statistical learning comes mainly from studies conducted in carefully controlled settings without auditory distraction. While such conditions permit careful examination of learning, they do not reflect the naturalistic language learning experience, which is replete with auditory distraction – including competing talkers. Here, we examine how statistical language learning proceeds in a virtual cocktail party environment, where the to-be-learned input is presented alongside a competing speech stream with its own distributional regularities. During exposure, participants in the Dual Talker group concurrently heard two novel languages, one produced by a female talker and one by a male talker, with each talker virtually positioned at opposite sides of the listener (left/right) using binaural acoustic manipulations. Selective attention was manipulated by instructing participants to attend to only one of the two talkers. At test, participants were asked to distinguish words from part-words for both the attended and the unattended languages. Results indicated that participants’ accuracy was significantly higher for trials from the attended vs. unattended
language. Further, the performance of this Dual Talker group was no different compared to a control group who heard only one language from a single talker (Single Talker group). We thus conclude that statistical learning is modulated by selective attention, being relatively robust against the additional cognitive load provided by competing speech, emphasizing its efficiency in naturalistic language learning situations.

Abstract

Natural speech involves repair. These repairs are often highlighted through prosodic marking (Levelt & Cutler, 1983). Prosodic marking usually entails an increase in pitch, loudness, and/or duration that draws attention to the corrected word. While it is established that natural self-repairs typically elicit prosodic marking, the exact cause of this is unclear. This study investigates whether producing a prosodic marking emerges from an automatic correction process or has a communicative purpose. In the current study, we elicit corrections to test whether all self-corrections elicit prosodic marking. Participants carried out a picture-naming task in which they described two images presented on-screen. To prompt self-correction, the second image was altered in some cases, requiring participants to abandon their initial utterance and correct their description to match the new image. This manipulation was compared to a control condition in which only the orientation of the object would change, eliciting no self-correction while still presenting a visual change. We found that the replacement of the item did not elicit a prosodic marking, regardless of the type of change. Theoretical implications and research directions are discussed, in particular theories of prosodic planning.

Abstract

It has been shown that when speakers produce hand gestures, addressees are attentive towards these gestures, using them to facilitate speech processing. Even relatively simple “beat” gestures are taken into account to help process aspects of speech such as prosodic prominence. In fact, recent evidence suggests that the timing of a beat gesture can influence spoken word recognition. Termed the manual McGurk Effect, Dutch participants, when presented with lexical stress minimal pair continua in Dutch, were biased to hear lexical stress on the syllable that coincided with a beat gesture. However, little is known about how this manual McGurk effect would surface in languages other than Dutch, with different acoustic cues to prominence, and variable gestures. Therefore, this study tests the effect in Spanish where lexical stress is arguably even more important, being a contrastive cue in the regular verb conjugation system. Results from 24 participants corroborate the effect in Spanish, namely that when given the same auditory stimulus, participants were biased to perceive lexical stress on the syllable that visually co-occurred with a beat gesture. These findings extend the manual McGurk effect to a different language, emphasizing the impact of gestures' timing on prosody perception and spoken word recognition.

Abstract

Studies investigating language commonly isolate one modality or process, focusing on comprehension or production. Here, we present a framework for a paradigm that combines both: the Concise Language Paradigm (CLaP), tapping into comprehension and production within one trial. The trial structure is identical across conditions, presenting a sentence followed by a picture to be named. We tested 21 healthy speakers with EEG to examine three time periods during a trial (sentence, pre-picture interval, picture onset), yielding contrasts of sentence comprehension, contextually and visually guided word retrieval, object recognition, and naming. In the CLaP, sentences are presented auditorily (constrained, unconstrained, reversed), and pictures appear as normal (constrained, unconstrained, bare) or scrambled objects. Imaging results revealed different evoked responses after sentence onset for normal and time-reversed speech. Further, we replicated the context effect of alpha-beta power decreases before picture onset for constrained relative to unconstrained sentences, and could clarify that this effect arises from power decreases following constrained sentences. Brain responses locked to picture-onset differed as a function of sentence context and picture type (normal vs. scrambled), and naming times were fastest for pictures in constrained sentences, followed by scrambled picture naming, and equally fast for bare and unconstrained picture naming. Finally, we also discuss the potential of the CLaP to be adapted to different focuses, using different versions of the linguistic content and tasks, in combination with electrophysiology or other imaging methods. These first results of the CLaP indicate that this paradigm offers a promising framework to investigate the language system.

Abstract

Despite decades of study, we still know less than we would like about the association between joint attention (JA) and language acquisition. This is partly because of disagreements on how to operationalise JA. In this study, we examine the impact of applying two different, influential JA operationalisation schemes to the same dataset of child-caregiver interactions, to determine which yields a better fit to children's later vocabulary size. Two coding schemes— one defining JA in terms of gaze overlap and one in terms of social aspects of shared attention—were applied to video-recordings of dyadic naturalistic toy-play interactions (N=45). We found that JA was predictive of later production vocabulary when operationalised as shared focus (study 1), but also that its operationalisation as shared social awareness increased its predictive power (study 2). Our results emphasise the critical role of methodological choices in understanding how and why JA is associated with vocabulary size.

Abstract

Different talkers speak differently, even within the same homogeneous group. These differences lead to acoustic variability in speech, causing challenges for correct perception of the intended message. Because previous descriptions of this acoustic variability have focused mostly on segments, talker variability in prosodic structures is not yet well documented. The present study therefore examined acoustic between-talker variability in word stress in Dutch. We recorded 40 native Dutch talkers from a participant sample with minimal dialectal variation and balanced gender, producing segmentally overlapping words (e.g., VOORnaam vs. voorNAAM; ‘first name’ vs. ‘respectable’, capitalization indicates lexical stress), and measured different acoustic cues to stress. Each individual participant’s acoustic measurements were analyzed using Linear Discriminant Analyses, which provide coefficients for each cue, reflecting the strength of each cue in a talker’s productions. On average, talkers primarily used mean F0, intensity, and duration. Moreover, each participant also employed a unique combination of cues, illustrating large prosodic variability between talkers. In fact, classes of cue-weighting tendencies emerged, differing in which cue was used as the main cue. These results offer the most comprehensive acoustic description, to date, of word stress in Dutch, and illustrate that large prosodic variability is present between individual talkers.

Abstract

Talkers vary in how they speak, resulting in acoustic variability in segments and prosody. Previous studies showed that listeners deal with segmental variability through perceptual learning and that these learning effects are stable over time. The present study examined whether this is also true for lexical stress variability. Listeners heard Dutch minimal pairs (e.g., VOORnaam vs. voorNAAM, ‘first name’ vs. ‘respectable’) spoken by two talkers. Half of the participants heard Talker 1 using only F0 to signal lexical stress and Talker 2 using only intensity. The other half heard the reverse. After a learning phase, participants were tested on words spoken by these talkers with conflicting stress cues (‘mixed items’; e.g., Talker 1 saying voornaam with F0 signaling initial stress and intensity signaling final stress). We found that, despite the conflicting cues, listeners perceived these items following what they had learned. For example, participants hearing the example mixed item described above who had learned that Talker 1 used F0 perceived initial stress (VOORnaam) but those who had learned that Talker 1 used intensity perceived final stress (voorNAAM). Crucially, this result was still present in a delayed test phase, showing that talker-specific learning about lexical stress is stable over time.

Abstract

When we understand language, we recognize words and combine them into sentences. In this article, we explore the hypothesis that listeners use probabilistic information about words to build syntactic structure. Recent work has shown that lexical probability and syntactic structure both modulate the delta-band (<4 Hz) neural signal. Here, we investigated whether the neural encoding of syntactic structure changes as a function of the distributional properties of a word. To this end, we analyzed MEG data of 24 native speakers of Dutch who listened to three fairytales with a total duration of 49 min. Using temporal response functions and a cumulative model-comparison approach, we evaluated the contributions of syntactic and distributional features to the variance in the delta-band neural signal. This revealed that lexical surprisal values (a distributional feature), as well as bottom-up node counts (a syntactic feature) positively contributed to the model of the delta-band neural signal. Subsequently, we compared responses to the syntactic feature between words with high- and low-surprisal values. This revealed a delay in the response to the syntactic feature as a consequence of the surprisal value of the word: high-surprisal values were associated with a delayed response to the syntactic feature by 150–190 ms. The delay was not affected by word duration, and did not have a lexical origin. These findings suggest that the brain uses probabilistic information to infer syntactic structure, and highlight an importance for the role of time in this process.

Abstract

During face-to-face conversation, transitions between speaker turns are incredibly fast. These fast turn exchanges seem to involve next speakers predicting upcoming semantic information, such that next turn planning can begin before a current turn is complete. Given that face-to-face conversation also involves the use of communicative bodily signals, an important question is how bodily signals such as co-speech hand gestures play into these processes of prediction and fast responding. In this corpus study, we found that hand gestures that depict or refer to semantic information started before the corresponding information in speech, which held both for the onset of the gesture as a whole, as well as the onset of the stroke (the most meaningful part of the gesture). This early timing potentially allows listeners to use the gestural information to predict the corresponding semantic information to be conveyed in speech. Moreover, we provided further evidence that questions with gestures got faster responses than questions without gestures. However, we found no evidence for the idea that how much a gesture precedes its lexical affiliate (i.e., its predictive potential) relates to how fast responses were given. The findings presented here highlight the importance of the temporal relation between speech and gesture and help to illuminate the potential mechanisms underpinning multimodal language processing during face-to-face conversation.

Abstract

Most language use occurs in face-to-face conversation, which involves rapid turn-taking. Seeing communicative bodily signals in addition to hearing speech may facilitate such fast responding. We tested whether this holds for co-speech hand gestures by investigating whether these gestures speed up button press responses to questions. Sixty native speakers of Dutch viewed videos in which an actress asked yes/no-questions, either with or without a corresponding iconic hand gesture. Participants answered the questions as quickly and accurately as possible via button press. Gestures did not impact response accuracy, but crucially, gestures sped up responses, suggesting that response planning may be finished earlier when gestures are seen. How much gestures sped up responses was not related to their timing in the question or their timing with respect to the corresponding information in speech. Overall, these results are in line with the idea that multimodality may facilitate fast responding during face-to-face conversation.

Abstract

The typical pattern of alternating turns in conversation seems trivial at first sight. But a closer look quickly reveals the cognitive challenges involved, with much of it resulting from the fast-paced nature of conversation. One core ingredient to turn coordination is the anticipation of upcoming turn ends so as to be able to ready oneself for providing the next contribution. Across two experiments, we investigated two variables inherent to face-to-face conversation, the presence of visual bodily signals and preceding discourse context, in terms of their contribution to turn end anticipation. In a reaction time paradigm, participants anticipated conversational turn ends better when seeing the speaker and their visual bodily signals than when they did not, especially so for longer turns. Likewise, participants were better able to anticipate turn ends when they had access to the preceding discourse context than when they did not, and especially so for longer turns. Critically, the two variables did not interact, showing that visual bodily signals retain their influence even in the context of preceding discourse. In a pre-registered follow-up experiment, we manipulated the visibility of the speaker's head, eyes and upper body (i.e. torso + arms). Participants were better able to anticipate turn ends when the speaker's upper body was visible, suggesting a role for manual gestures in turn end anticipation. Together, these findings show that seeing the speaker during conversation may critically facilitate turn coordination in interaction.

Abstract

Bilinguals possess the ability of expressing themselves in more than one language, and typically do so in contextually rich and dynamic settings. Theories and models have indeed long considered context factors to affect bilingual language production in many ways. However, most experimental studies in this domain have failed to fully incorporate linguistic, social, or physical context aspects, let alone combine them in the same study. Indeed, most experimental psycholinguistic research has taken place in isolated and constrained lab settings with carefully selected words or sentences, rather than under rich and naturalistic conditions. We argue that the most influential experimental paradigms in the psycholinguistic study of bilingual language production fall short of capturing the effects of context on language processing and control presupposed by prominent models. This paper therefore aims to enrich the methodological basis for investigating context aspects in current experimental paradigms and thereby move the field of bilingual language production research forward theoretically. After considering extensions of existing paradigms proposed to address context effects, we present three far-ranging innovative proposals, focusing on virtual reality, dialog situations, and multimodality in the context of bilingual language production.

Abstract

Bilinguals, by definition, are capable of expressing themselves in more than one language. But which cognitive mechanisms allow them to switch from one language to another? Previous experimental research using the cued language-switching paradigm supports theoretical models that assume that both transient, reactive and sustained, proactive inhibitory mechanisms underlie bilinguals’ capacity to flexibly and efficiently control which language they use. Here we used immersive virtual reality to test the extent to which these inhibitory mechanisms may be active when unbalanced Dutch-English bilinguals i) produce full sentences rather than individual words, ii) to a life-size addressee rather than only into a microphone, iii) using a message that is relevant to that addressee rather than communicatively irrelevant, iv) in a rich visual environment rather than in front of a computer screen. We observed a reversed language dominance paired with switch costs for the L2 but not for the L1 when participants were stand owners in a virtual marketplace and informed their monolingual customers in full sentences about the price of their fruits and vegetables. These findings strongly suggest that the subtle balance between the application of reactive and proactive inhibitory mechanisms that support bilingual language control may be different in the everyday life of a bilingual compared to in the (traditional) psycholinguistic laboratory.

Abstract

The human brain deals with the infinite variability of speech through multiple mechanisms. Some of them rely solely on information in the speech input (i.e., signal-driven) whereas some rely on linguistic or real-world knowledge (i.e., knowledge-driven). Many signal-driven perceptual processes rely on the enhancement of acoustic differences between incoming speech sounds, producing contrastive adjustments. For instance, when an ambiguous voiceless fricative is preceded by a high fundamental frequency (f0) sentence, the fricative is perceived as having lower a spectral center of gravity (CoG). However, it is not clear whether knowledge of a talker’s typical f0 can lead to similar contrastive effects. This study investigated a possible talker f0 effect on fricative CoG perception. In the exposure phase, two groups of participants (N=16 each) heard the same talker at high or low f0 for 20 minutes. Later, in the test phase, participants rated fixed-f0 /?ɔk/ tokens as being /sɔk/ (i.e., high CoG) or /ʃɔk/ (i.e., low CoG), where /?/ represents a fricative from a 5-step /s/-/ʃ/ continuum. Surprisingly, the data revealed the opposite of our contrastive hypothesis, whereby hearing high f0 instead biased perception towards high CoG. Thus, we demonstrated that talker f0 information affects fricative CoG perception.

Abstract

How people communicate about motion events and how this is shaped by language typology are mostly studied with a focus on linguistic encoding in speech. Yet, human communication typically involves an interactional exchange of multimodal signals, such as hand gestures that have different affordances for representing event components. Here, we review recent empirical evidence on multimodal encoding of motion in speech and gesture to gain a deeper understanding of whether and how language typology shapes linguistic expressions in different modalities, and how this changes across different sensory modalities of input and interacts with other aspects of cognition. Empirical evidence strongly suggests that Talmy’s typology of event integration predicts multimodal event descriptions in speech and gesture and visual attention to event components prior to producing these descriptions. Furthermore, variability within the event itself, such as type and modality of stimuli, may override the influence of language typology, especially for expression of manner.

Abstract

Background

The number of words children produce (expressive vocabulary) and understand (receptive vocabulary) changes rapidly during early development, partially due to genetic factors. Here, we performed a meta–genome-wide association study of vocabulary acquisition and investigated polygenic overlap with literacy, cognition, developmental phenotypes, and neurodevelopmental conditions, including attention-deficit/hyperactivity disorder (ADHD).

Methods

We studied 37,913 parent-reported vocabulary size measures (English, Dutch, Danish) for 17,298 children of European descent. Meta-analyses were performed for early-phase expressive (infancy, 15–18 months), late-phase expressive (toddlerhood, 24–38 months), and late-phase receptive (toddlerhood, 24–38 months) vocabulary. Subsequently, we estimated single nucleotide polymorphism–based heritability (SNP-h2) and genetic correlations (rg) and modeled underlying factor structures with multivariate models.

Results

Early-life vocabulary size was modestly heritable (SNP-h2 = 0.08–0.24). Genetic overlap between infant expressive and toddler receptive vocabulary was negligible (rg = 0.07), although each measure was moderately related to toddler expressive vocabulary (rg = 0.69 and rg = 0.67, respectively), suggesting a multifactorial genetic architecture. Both infant and toddler expressive vocabulary were genetically linked to literacy (e.g., spelling: rg = 0.58 and rg = 0.79, respectively), underlining genetic similarity. However, a genetic association of early-life vocabulary with educational attainment and intelligence emerged only during toddlerhood (e.g., receptive vocabulary and intelligence: rg = 0.36). Increased ADHD risk was genetically associated with larger infant expressive vocabulary (rg = 0.23). Multivariate genetic models in the ALSPAC (Avon Longitudinal Study of Parents and Children) cohort confirmed this finding for ADHD symptoms (e.g., at age 13; rg = 0.54) but showed that the association effect reversed for toddler receptive vocabulary (rg = −0.74), highlighting developmental heterogeneity.

Conclusions

The genetic architecture of early-life vocabulary changes during development, shaping polygenic association patterns with later-life ADHD, literacy, and cognition-related traits.

Abstract

Electrophysiological brain activity has been shown to synchronize with the quasi-regular repetition of grammatical phrases in connected speech—so-called phrase-rate neural tracking. Current debate centers around whether this phenomenon is best explained in terms of the syntactic properties of phrases or in terms of syntax-external information, such as the sequential repetition of parts of speech. As these two factors were confounded in previous studies, much of the literature is compatible with both accounts. Here, we used electroencephalography (EEG) to determine if and when the brain is sensitive to both types of information. Twenty native speakers of Mandarin Chinese listened to isochronously presented streams of monosyllabic words, which contained either grammatical two-word phrases (e.g., catch fish, sell house) or non-grammatical word combinations (e.g., full lend, bread far). Within the grammatical conditions, we varied two structural factors: the position of the head of each phrase and the type of attachment. Within the non-grammatical conditions, we varied the consistency with which parts of speech were repeated. Tracking was quantified through evoked power and inter-trial phase coherence, both derived from the frequency-domain representation of EEG responses. As expected, neural tracking at the phrase rate was stronger in grammatical sequences than in non-grammatical sequences without syntactic structure. Moreover, it was modulated by both attachment type and head position, revealing the structure-sensitivity of phrase-rate tracking. We additionally found that the brain tracks the repetition of parts of speech in non-grammatical sequences. These data provide an integrative perspective on the current debate about neural tracking effects, revealing that the brain utilizes regularities computed over multiple levels of linguistic representation in guiding rhythmic computation.

Abstract

Rhythmic patterns in interactive contexts characterize human behaviours such as conversational turn-taking. These timed patterns are also present in other animals, and often described as rhythm. Understanding fine-grained temporal adjustments in interaction requires complementary quantitative methodologies. Here, we showcase how vocal interactive rhythmicity in a non-human animal can be quantified using a multi-method approach. We record vocal interactions in harbour seal pups (Phoca vitulina) under controlled conditions. We analyse these data by combining analytical approaches, namely categorical rhythm analysis, circular statistics and time series analyses. We test whether pups' vocal rhythmicity varies across behavioural contexts depending on the absence or presence of a calling partner. Four research questions illustrate which analytical approaches are complementary versus orthogonal. For our data, circular statistics and categorical rhythms suggest that a calling partner affects a pup's call timing. Granger causality suggests that pups predictively adjust their call timing when interacting with a real partner. Lastly, the ADaptation and Anticipation Model estimates statistical parameters for a potential mechanism of temporal adaptation and anticipation. Our analytical complementary approach constitutes a proof of concept; it shows feasibility in applying typically unrelated techniques to seals to quantify vocal rhythmic interactivity across behavioural contexts.

Abstract

Eye gaze is a powerful ostensive cue in infant-caregiver interactions, with demonstrable effects on language acquisition. While the link between gaze following and later vocabulary is well-established, the effects of eye gaze on other aspects of language, such as speech processing, are less clear. In this EEG study, we examined the effects of the speaker’s eye gaze on ten-month-old infants’ neural tracking of naturalistic audiovisual speech, a marker for successful speech processing. Infants watched videos of a speaker telling stories, addressing the infant with direct or averted eye gaze. We assessed infants’ speech-brain coherence at stress (1–1.75 Hz) and syllable (2.5–3.5 Hz) rates, tested for differences in attention by comparing looking times and EEG theta power in the two conditions, and investigated whether neural tracking predicts later vocabulary. Our results showed that infants’ brains tracked the speech rhythm both at the stress and syllable rates, and that infants’ neural tracking at the syllable rate predicted later vocabulary. However, speech-brain coherence did not significantly differ between direct and averted gaze conditions and infants did not show greater attention to direct gaze. Overall, our results suggest significant neural tracking at ten months, related to vocabulary development, but not modulated by speaker’s gaze.

Abstract

The current study investigated how the role of pitch in one’s native language and L2 experience influenced musical melodic processing by testing Turkish and Mandarin Chinese advanced and beginning learners of English as an L2. Pitch has a lower functional load and shows a simpler pattern in Turkish than in Chinese as the former only contrasts between presence and the absence of pitch elevation, while the latter makes use of four different pitch contours lexically. Using the Musical Ear Test as the tool, we found that the Chinese listeners outperformed the Turkish listeners, and the advanced L2 learners outperformed the beginning learners. The Turkish listeners were further tested on their discrimination of bisyllabic Chinese lexical tones, and again an L2 advantage was observed. No significant difference was found for working memory between the beginning and advanced L2 learners. These results suggest that richness of tonal inventory of the native language is essential for triggering a music processing advantage, and on top of the tone language advantage, the L2 experience yields a further enhancement. Yet, unlike the tone language advantage that seems to relate to pitch expertise, learning an L2 seems to improve sound discrimination in general, and such improvement exhibits in non-native lexical tone discrimination.

Abstract

Previous electroencephalography studies have yielded evidence for automatic processing of syntax and lexical stress. However, these studies looked at both effects in isolation, limiting their generalizability to everyday language comprehension. In the current study, we investigated automatic processing of grammatical agreement in the face of variation in lexical stress. Using an oddball paradigm, we measured the Mismatch Negativity (MMN) in Dutch-speaking participants while they listened to Dutch subject–verb sequences (linguistic context) or acoustically similar sequences in which the subject was replaced by filtered noise (nonlinguistic context). The verb forms differed in the inflectional suffix, rendering the subject–verb sequences grammatically correct or incorrect, and leading to a difference in the stress pattern of the verb forms. We found that the MMNs were modulated in both the linguistic and nonlinguistic condition, suggesting that the processing load induced by variation in lexical stress can hinder early automatic processing of grammatical agreement. However, as the morphological differences between the verb forms correlated with differences in number of syllables, an interpretation in terms of the prosodic structure of the sequences cannot be ruled out. Future research is needed to determine which of these factors (i.e., lexical stress, syllabic structure) most strongly modulate early syntactic processing.

Abstract

Since the cognitive revolution, language and action have been compared as cognitive systems, with cross-domain convergent views recently gaining renewed interest in biology, neuroscience, and cognitive science. Language and action are both combinatorial systems whose mode of combination has been argued to be hierarchical, combining elements into constituents of increasingly larger size. This structural similarity has led to the suggestion that they rely on shared cognitive and neural resources. In this article, we compare the conceptual and formal properties of hierarchy in language and action using set theory. We show that the strong compositionality of language requires a particular formalism, a magma, to describe the algebraic structure corresponding to the set of hierarchical structures underlying sentences. When this formalism is applied to actions, it appears to be both too strong and too weak. To overcome these limitations, which are related to the weak compositionality and sequential nature of action structures, we formalize the algebraic structure corresponding to the set of actions as a trace monoid. We aim to capture the different system properties of language and action in terms of the distinction between hierarchical sets and hierarchical sequences and discuss the implications for the way both systems could be represented in the brain.

Abstract

Artificial neural networks (ANNs) inspired by biology are beginning to be widely used to model behavioural and neural data, an approach we call ‘neuroconnectionism’. ANNs have been not only lauded as the current best models of information processing in the brain but also criticized for failing to account for basic cognitive functions. In this Perspective article, we propose that arguing about the successes and failures of a restricted set of current ANNs is the wrong approach to assess the promise of neuroconnectionism for brain science. Instead, we take inspiration from the philosophy of science, and in particular from Lakatos, who showed that the core of a scientific research programme is often not directly falsifiable but should be assessed by its capacity to generate novel insights. Following this view, we present neuroconnectionism as a general research programme centred around ANNs as a computational language for expressing falsifiable theories about brain computation. We describe the core of the programme, the underlying computational framework and its tools for testing specific neuroscientific hypotheses and deriving novel understanding. Taking a longitudinal view, we review past and present neuroconnectionist projects and their responses to challenges and argue that the research programme is highly progressive, generating new and otherwise unreachable insights into the workings of the brain.

Abstract

Prior work has shown that internal representations of artificial neural networks can significantly predict brain responses elicited by unimodal stimuli (i.e. reading a book chapter or viewing static images). However, the computational modeling of brain representations of naturalistic video stimuli, such as movies or TV shows, still remains underexplored. In this work, we present a promising approach for modeling vision-language brain representations of video stimuli by a transformer-based model that represents videos jointly through audio, text, and vision. We show that the joint representations of vision and text information are better aligned with brain representations of subjects watching a popular TV show. We further show that the incorporation of visual information improves brain alignment across several regions that support language processing.

Abstract

How do neural oscillations support human audiovisual language and communication? Considering the rhythmic nature of audiovisual language, in which stimuli from different sensory modalities unfold over time, neural oscillations represent an ideal candidate to investigate how audiovisual language is processed in the brain. Modulations of oscillatory phase and power are thought to support audiovisual language and communication in multiple ways. Neural oscillations synchronize by tracking external rhythmic stimuli or by re-setting their phase to presentation of relevant stimuli, resulting in perceptual benefits. In particular, synchronized neural oscillations have been shown to subserve the processing and the integration of auditory speech, visual speech, and hand gestures. Furthermore, synchronized oscillatory modulations have been studied and reported between brains during social interaction, suggesting that their contribution to audiovisual communication goes beyond the processing of single stimuli and applies to natural, face-to-face communication.

There are still some outstanding questions that need to be answered to reach a better understanding of the neural processes supporting audiovisual language and communication. In particular, it is not entirely clear yet how the multitude of signals encountered during audiovisual communication are combined into a coherent percept and how this is affected during real-world dyadic interactions. In order to address these outstanding questions, it is fundamental to consider language as a multimodal phenomenon, involving the processing of multiple stimuli unfolding at different rhythms over time, and to study language in its natural context: social interaction. Other outstanding questions could be addressed by implementing novel techniques (such as rapid invisible frequency tagging, dual-electroencephalography, or multi-brain stimulation) and analysis methods (e.g., using temporal response functions) to better understand the relationship between oscillatory dynamics and efficient audiovisual communication.

Abstract

Learning can occur via trial and error; however, learning from conspecifics is faster and more efficient. Social animals can easily learn from conspecifics, but how do less social species learn? In particular, birds provide astonishing examples of social learning of vocalizations, while vocal learning from conspecifics is much less understood in mammals. We present a hypothesis aimed at solving an apparent paradox: how can harbor seals (Phoca vitulina) learn their song when their whole lives are marked by loose conspecific social contact? Harbor seal pups are raised individually by their mostly silent mothers. Pups' first few weeks of life show developed vocal plasticity; these weeks are followed by relatively silent years until sexually mature individuals start singing. How can this rather solitary life lead to a learned song? Why do pups display vocal plasticity at a few weeks of age, when this is apparently not needed? Our hypothesis addresses these questions and tries to explain how vocal learning fits into the natural history of harbor seals, and potentially other less social mammals. We suggest that harbor seals learn during a sensitive period within puppyhood, where they are exposed to adult males singing. In particular, we hypothesize that, to make this learning possible, the following happens concurrently: (1) mothers give birth right before male singing starts, (2) pups enter a sensitive learning phase around weaning time, which (3) coincides with their foraging expeditions at sea which, (4) in turn, coincide with the peak singing activity of adult males. In other words, harbor seals show vocal learning as pups so they can acquire elements of their future song from adults, and solitary adults can sing because they have acquired these elements as pups. We review the available evidence and suggest that pups learn adult vocalizations because they are born exactly at the right time to eavesdrop on singing adults. We conclude by advancing empirical predictions and testable hypotheses for future work.

Abstract

This article explores the role of text and reader characteristics in character engagement experiences. In an online study, participants completed several self-report and behavioral measures of social-cognitive abilities and read two literary narratives in which the presence of linguistic viewpoint markers was varied using a highly controlled manipulation strategy. Afterward, participants reported on their character engagement experiences. A principal component analysis on participants’ responses revealed the multidimensional nature of character engagement, which included both self- and other-oriented emotional responses (e.g., empathy, personal distress) as well as more cognitive responses (e.g., identification, perspective taking). Furthermore, character engagement was found to rely on a wide range of social-cognitive abilities but not on the presence of viewpoint markers. Finally, and most importantly, we did not find convincing evidence for an interplay between social-cognitive abilities and the presence of viewpoint markers. These findings suggest that readers rely on their social-cognitive abilities to engage with the inner worlds of fictional others, more so than on the lexical cues of those inner worlds provided by the text.

Abstract

We present a visual world eye-tracking study on Tseltal (a Mayan language) and investigate whether verbal information can be used to anticipate an upcoming referent. Basic word order in transitive sentences in Tseltal is Verb-Object-Subject (VOS). The verb is usually encountered first, making argument structure and syntactic information available at the outset, which should facilitate anticipation of the post-verbal arguments. Tseltal speakers listened to verb-initial sentences with either an object-predictive verb (e.g., ‘eat’) or a general verb (e.g., ‘look for’) (e.g., “Ya slo’/sle ta stukel on te kereme”, Is eating/is looking (for) by himself the avocado the boy/ “The boy is eating/is looking (for) an avocado by himself”) while seeing a visual display showing one potential referent (e.g., avocado) and three distractors (e.g., bag, toy car, coffee grinder). We manipulated verb type (predictive vs. general) and recorded participants' eye-movements while they listened and inspected the visual scene. Participants’ fixations to the target referent were analysed using multilevel logistic regression models. Shortly after hearing the predictive verb, participants fixated the target object before it was mentioned. In contrast, when the verb was general, fixations to the target only started to increase once the object was heard. Our results suggest that Tseltal hearers pre-activate semantic features of the grammatical object prior to its linguistic expression. This provides evidence from a verb-initial language for online incremental semantic interpretation and anticipatory processing during language comprehension. These processes are comparable to the ones identified in subject-initial languages, which is consistent with the notion that different languages follow similar universal processing principles.

Abstract

Schizophrenia is a debilitating psychiatric disorder associated with a reduced fertility and decreased life expectancy, yet common predisposing variation substantially contributes to the onset of the disorder, which poses an evolutionary paradox. Previous research has suggested balanced selection, a mechanism by which schizophrenia risk alleles could also provide advantages under certain environments, as a reliable explanation. However, recent studies have shown strong evidence against a positive selection of predisposing loci. Furthermore, evolutionary pressures on schizophrenia risk alleles could have changed throughout human history as new environments emerged. Here in this study, we used 1000 Genomes Project data to explore the relationship between schizophrenia predisposing loci and recent natural selection (RNS) signatures after the human diaspora out of Africa around 100,000 years ago on a genome-wide scale. We found evidence for significant enrichment of RNS markers in derived alleles arisen during human evolution conferring protection to schizophrenia. Moreover, both partitioned heritability and gene set enrichment analyses of mapped genes from schizophrenia predisposing loci subject to RNS revealed a lower involvement in brain and neuronal related functions compared to those not subject to RNS. Taken together, our results suggest non-antagonistic pleiotropy as a likely mechanism behind RNS that could explain the persistence of schizophrenia common predisposing variation in human populations due to its association to other non-psychiatric phenotypes.

Abstract

Semantic variation in the cutting and breaking domain has been shown to be constrained across languages in a previous typological study, but it was unclear whether Japanese was an outlier in this domain. Here we revisit cutting and breaking in the Japonic language area by collecting new naming data for 40 videoclips depicting cutting and breaking events in Standard Japanese, the highly divergent Tohoku dialects, as well as four related Ryukyuan languages (Amami, Okinawa, Miyako and Yaeyama). We find that the Japonic languages recapitulate the same semantic dimensions attested in the previous typological study, confirming that semantic variation in the domain of cutting and breaking is indeed cross-linguistically constrained. We then compare our new Japonic data to previously collected Germanic data and find that, in general, related languages resemble each other more than unrelated languages, and that the Japonic languages resemble each other more than the Germanic languages do. Nevertheless, English resembles all of the Japonic languages more than it resembles Swedish. Together, these findings show that the rate and extent of semantic change can differ between language families, indicating the existence of lineage-specific developments on top of universal cross-linguistic constraints.