Publications

Abstract

Linguistic expressions of time often draw on spatial language, which raises the question of whether cultural specificity in spatial language and cognition is reflected in thinking about time. In the Mayan language Tzeltal, spatial language relies heavily on an absolute frame of reference utilizing the overall slope of the land, distinguishing an “uphill/downhill” axis oriented from south to north, and an orthogonal “crossways” axis (sunrise-set) on the basis of which objects at all scales are located. Does this absolute system for calculating spa-tial relations carry over into construals of temporal relations? This question was explored in a study where Tzeltal consultants produced temporal expressions and performed two different non-linguistic temporal ordering tasks. The results show that at least five distinct schemata for conceptualizing time underlie Tzeltal linguistic expressions: (i) deictic ego-centered time, (ii) time as an ordered sequence (e.g., “first”/“later”), (iii) cyclic time (times of the day, seasons), (iv) time as spatial extension or location (e.g., “entering/exiting July”), and (v) a time vector extending uphillwards into the future. The non-linguistic task results showed that the “time moves uphillwards” metaphor, based on the absolute frame of reference prevalent in Tzeltal spatial language and thinking and important as well in the linguistic expressions for time, is not strongly reflected in responses on these tasks. It is argued that systematic and consistent use of spatial language in an absolute frame of reference does not necessarily transfer to consistent absolute time conceptualization in non-linguistic tasks; time appears to be more open to alternative construals.

Abstract

The Hmong Diaspora is one of the widest modern human migrations. Mainly localised in South-East Asia, the United States of America, and metropolitan France, a small community has also settled the Amazonian forest of French Guiana. We have biologically analysed 62 individuals of this unique Guianese population through three complementary genetic markers: mitochondrial DNA (HVS-I/II and coding region SNPs), Y-chromosome (SNPs and STRs), and the Gm allotypic system. All genetic systems showed a high conservation of the Asian gene pool (Asian ancestry: mtDNA = 100.0%; NRY = 99.1%; Gm = 96.6%), without a trace of founder effect. When compared across various Asian populations, the highest correlations were observed with Hmong-Mien groups still living in South-East Asia (Fst < 0.05; P-value < 0.05). Despite a long history punctuated by exodus, the French Guianese Hmong have maintained their original genetic diversity.

Abstract

Two languages, historically related, both have lexical stress, with word stress distinctions signalled in each by the same suprasegmental cues. In each language, words can overlap segmentally but differ in placement of primary versus secondary stress (OCtopus, ocTOber). However, secondary stress occurs more often in the words of one language, Dutch, than in the other, English, and largely because of this, Dutch listeners find it helpful to use suprasegmental stress cues when recognising spoken words. English listeners, in contrast, do not; indeed, Dutch listeners can outdo English listeners in correctly identifying the source words of English word fragments (oc-). Here we show that Dutch-native listeners who reside in an English-speaking environment and have become dominant in English, though still maintaining their use of these stress cues in their L1, ignore the same cues in their L2 English, performing as poorly in the fragment identification task as the L1 English do.

Abstract

A consistent finding across head-initial languages, such as English, is that subject relative clauses (SRCs) are easier to comprehend than object relative clauses (ORCs). However, several studies in Mandarin Chinese, a head-final language, revealed the opposite pattern, which might be modulated by working memory (WM) as suggested by recent results from self-paced reading performance. In the present study, event-related potentials (ERPs) were recorded when participants with high and low WM spans (measured by forward digit span and operation span tests) read Chinese ORCs and SRCs. The results revealed an N400-P600 complex elicited by ORCs on the relativizer, whose magnitude was modulated by the WM span. On the other hand, a P600 effect was elicited by SRCs on the head noun, whose magnitude was not affected by the WM span. These findings paint a complex picture of relative clause processing in Chinese such that opposing factors involving structural ambiguities and integration of filler-gap dependencies influence processing dynamics in Chinese relative clauses.

Abstract

Introduction
Despite abundant research on the role of Broca's area in language processing, there is still no consensus on language specificity of this region and its connectivity network.

Methods
The present study employed the meta-analytic connectivity modeling procedure to identify and compare domain-specific (language-specific) and domain-general (shared between language and other domains) functional connectivity patterns of three subdivisions within the broadly defined Broca's area: pars opercularis (IFGop), pars triangularis (IFGtri), and pars orbitalis (IFGorb) of the left inferior frontal gyrus.

Results
The findings revealed a left-lateralized frontotemporal network for all regions of interest underlying domain-specific linguistic functions. The domain-general network, however, spanned frontoparietal regions that overlap with the multiple-demand network and subcortical regions spanning the thalamus and the basal ganglia.

Conclusions
The findings suggest that language specificity of Broca's area emerges within a left-lateralized frontotemporal network, and that domain-general resources are garnered from frontoparietal and subcortical networks when required by task demands.

Abstract

Do all humans perceive, think, and talk about tree cover ("forests") in more or less the same way? International forestry programs frequently seem to operate on the assumption that they do. However, recent advances in the language sciences show that languages vary greatly as to how the landscape domain is lexicalized and grammaticalized. Different languages segment and label the large-scale environment and its features according to astonishingly different semantic principles, often in tandem with highly culture-specific practices and ideologies. Presumed basic concepts like mountain, valley, and river cannot in fact be straightforwardly translated across languages. In this paper we describe, compare, and evaluate some of the semantic diversity observed in relation to forests. We do so on the basis of first-hand linguistic field data from a global sample of indigenous categorization systems as they are manifested in the following languages: Avatime (Ghana), Duna (Papua New Guinea), Jahai (Malay Peninsula), Lokono (the Guianas), Makalero (East Timor), and Umpila/Kuuku Ya'u (Cape York Peninsula). We show that basic linguistic categories relating to tree cover vary considerably in their principles of semantic encoding across languages, and that forest is a challenging category from the point of view of intercultural translatability. This has consequences for current global policies and programs aimed at standardizing forest definitions and measurements. It calls for greater attention to categorial diversity in designing and implementing such agendas, and for receptiveness to and understanding of local indigenous classification systems in communicating those agendas on the ground.

Abstract

Nuclear receptors (NRs) form a large superfamily of transcription factors that participate in virtually every key biological process. They control development, fertility, gametogenesis and are misregulated in many cancers. Their enormous functional plasticity as transcription factors relates in part to NR-mediated interactions with hundreds of coregulatory proteins upon ligand (e.g., hormone) binding to their ligand binding domains (LBD), or following covalent modification. Some coregulator association relates to the distinct residues that shape a coactivator binding pocket termed AF-2, a surface groove that primarily determines the preference and specificity of protein–protein interactions. However, the highly conserved AF-2 pocket in the NR superfamily appears to be insufficient to account for NR subtype specificity leading to fine transcriptional modulation in certain settings. Additional protein–protein interaction surfaces, most notably on their LBD, may contribute to modulating NR function. NR coregulators and chaperones, normally much larger than the NR itself, may also bind to such interfaces. In the case of the androgen receptor (AR) LBD surface, structural and functional data highlighted the presence of another site named BF-3, which lies at a distinct but topographically adjacent surface to AF-2. AR BF-3 is a hot spot for mutations involved in prostate cancer and androgen insensitivity syndromes, and some FDA-approved drugs bind at this site. Structural studies suggested an allosteric relationship between AF-2 and BF-3, as occupancy of the latter affected coactivator recruitment to AF-2. Physiological relevant partners of AR BF-3 have not been described as yet. The newly discovered site is highly conserved among the steroid receptors subclass, but is also present in other NRs. Several missense mutations in the BF-3 regions of these human NRs are implicated in pathology and affect their function in vitro. The fact that AR BF-3 pocket is a druggable site evidences its pharmacological potential. Compounds that may affect allosterically NR function by binding to BF-3 open promising avenues to develop type-specific NR modulators.

Abstract

Most human communication is between people who speak or sign the same languages. Nevertheless, communication is to some extent possible where there is no language in common, as every tourist knows. How this works is of some theoretical interest (Levinson 2006). A nice arena to explore this capacity is when deaf signers of different languages meet for the first time, and are able to use the iconic affordances of sign to begin communication. Here we focus on Other-Initiated Repair (OIR), that is, where one signer makes clear he or she does not understand, thus initiating repair of the prior conversational turn. OIR sequences are typically of a three-turn structure (Schegloff 2007) including the problem source turn (T-1), the initiation of repair (T0), and the turn offering a problem solution (T+1). These sequences seem to have a universal structure (Dingemanse et al. 2013). We find that in most cases where such OIR occur, the signer of the troublesome turn (T-1) foresees potential difficulty, and marks the utterance with 'try markers' (Sacks & Schegloff 1979, Moerman 1988) which pause to invite recognition. The signers use repetition, gestural holds, prosodic lengthening and eyegaze at the addressee as such try-markers. Moreover, when T-1 is try-marked this allows for faster response times of T+1 with respect to T0. This finding suggests that signers in these 'first encounter' situations actively anticipate potential trouble and, through try-marking, mobilize and facilitate OIRs. The suggestion is that heightened meta-linguistic awareness can be utilized to deal with these problems at the limits of our communicational ability.

Abstract

Background: Identifying age-related changes in cognition that contribute towards reduced driving performance is important for the development of interventions to improve older adults' driving and prolong the time that they can continue to drive. While driving, one is often required to switch from attending to events changing in time, to distribute attention spatially. Although there is extensive research into both spatial attention and temporal attention and how these change with age, the literature on switching between these modalities of attention is limited within any age group. Methods: Age groups (21-30, 40-49, 50-59, 60-69 and 70+ years) were compared on their ability to switch between detecting a target in a rapid serial visual presentation (RSVP) stream and detecting a target in a visual search display. To manipulate the cost of switching, the target in the RSVP stream was either the first item in the stream (Target 1st), towards the end of the stream (Target Mid), or absent from the stream (Distractor Only). Visual search response times and accuracy were recorded. Target 1st trials behaved as no-switch trials, as attending to the remaining stream was not necessary. Target Mid and Distractor Only trials behaved as switch trials, as attending to the stream to the end was required. Results: Visual search response times (RTs) were longer on "Target Mid" and "Distractor Only" trials in comparison to "Target 1st" trials, reflecting switch-costs. Larger switch-costs were found in both the 40-49 and 60-69 years group in comparison to the 21-30 years group when switching from the Target Mid condition. Discussion: Findings warrant further exploration as to whether there are age-related changes in the ability to switch between these modalities of attention while driving. If older adults display poor performance when switching between temporal and spatial attention while driving, then the development of an intervention to preserve and improve this ability would be beneficial. © 2017 Callaghan, Holland and Kessler.

Abstract

Word meaning processing in the brain involves ventrolateral temporal cortex, but a semantic contribution of the dorsal stream, especially frontocentral sensorimotor areas, has been controversial. We here examine brain activation during passive reading of object-related nouns from different semantic categories, notably animal, food, and tool words, matched for a range of psycholinguistic features. Results show ventral stream activation in temporal cortex along with category-specific activation patterns in both ventral and dorsal streams, including sensorimotor systems and adjacent pFC. Precentral activation reflected action-related semantic features of the word categories. Cortical regions implicated in mouth and face movements were sparked by food words, and hand area activation was seen for tool words, consistent with the actions implicated by the objects the words are used to speak about. Furthermore, tool words specifically activated the right cerebellum, and food words activated the left orbito-frontal and fusiform areas. We discuss our results in the context of category-specific semantic deficits in the processing of words and concepts, along with previous neuroimaging research, and conclude that specific dorsal and ventral areas in frontocentral and temporal cortex index visual and affective–emotional semantic attributes of object-related nouns and action-related affordances of their referent objects.

Abstract

Language comprehension engages a distributed network of frontotemporal, parietal, and sensorimotor regions, but it is still unclear how meaning of words and their semantic relationships are represented and processed within these regions and to which degrees lexico-semantic representations differ between regions and semantic types. We used fMRI and representational similarity analysis to relate word-elicited multivoxel patterns to semantic similarity between action and object words. In left inferior frontal (BA 44-45-47), left posterior middle temporal and left precentral cortex, the similarity of brain response patterns reflected semantic similarity among action-related verbs, as well as across lexical classes-between action verbs and tool-related nouns and, to a degree, between action verbs and food nouns, but not between action verbs and animal nouns. Instead, posterior inferior temporal cortex exhibited a reverse response pattern, which reflected the semantic similarity among object-related nouns, but not action-related words. These results show that semantic similarity is encoded by a range of cortical areas, including multimodal association (e.g., anterior inferior frontal, posterior middle temporal) and modality-preferential (premotor) cortex and that the representational geometries in these regions are partly dependent on semantic type, with semantic similarity among action-related words crossing lexical-semantic category boundaries.

Abstract

Neuronal populations code similar concepts by similar activity patterns across the human brain's semantic networks. However, it is unclear to what extent such meaning-to-symbol mapping reflects distributional statistics, or experiential information grounded in sensorimotor and emotional knowledge. We asked whether integrating distributional and experiential data better distinguished conceptual categories than each method taken separately. We examined the similarity structure of fMRI patterns elicited by visually presented action- and object-related words using representational similarity analysis (RSA). We found that the distributional and experiential/integrative models respectively mapped the high-dimensional semantic space in left inferior frontal, anterior temporal, and in left precentral, posterior inferior/middle temporal cortex. Furthermore, results from model comparisons uncovered category-specific similarity patterns, as both distributional and experiential models matched the similarity patterns for action concepts in left fronto-temporal cortex, whilst the experiential/integrative (but not distributional) models matched the similarity patterns for object concepts in left fusiform and angular gyrus.

Abstract

Speaking requires the temporally coordinated planning of core linguistic information, from conceptual meaning to articulation. Recent neurophysiological results suggested that these operations involve a cascade of neural events with subsequent onset times, whilst competing evidence suggests early parallel neural activation. To test these hypotheses, we examined the sources of neuromagnetic activity recorded from 34 participants overtly naming 134 images from 4 object categories (animals, tools, foods and clothes). Within each category, word length and phonological neighbourhood density were co-varied to target phonological/phonetic processes. Multivariate pattern analyses (MVPA) searchlights in source space decoded object categories in occipitotemporal and middle temporal cortex, and phonological/phonetic variables in left inferior frontal (BA 44) and motor cortex early on. The findings suggest early activation of multiple variables due to intercorrelated properties and interactivity of processing, thus raising important questions about the representational properties of target words during the preparatory time enabling overt speaking.

Abstract

Dyslexia is a common specific learning disability with a substantive genetic component. Several candidate genes have been proposed to be implicated in dyslexia susceptibility, such as DYX1C1, ROBO1, KIAA0319, and DCDC2. Associations with variants in these genes have also been reported with a variety of psychometric measures tapping into the underlying processes that might be impaired in dyslexic people. In this study, we first conducted a literature review to select single nucleotide polymorphisms (SNPs) in dyslexia candidate genes that had been repeatedly implicated across studies. We then assessed the SNPs for association in the richly phenotyped longitudinal data set from the Dutch Dyslexia Program. We tested for association with several quantitative traits, including word and nonword reading fluency, rapid naming, phoneme deletion, and nonword repetition. In this, we took advantage of the longitudinal nature of the sample to examine if associations were stable across four educational time-points (from 7 to 12 years). Two SNPs in the KIAA0319 gene were nominally associated with rapid naming, and these associations were stable across different ages. Genetic association analysis with complex cognitive traits can be enriched through the use of longitudinal information on trait development.

Abstract

Although the typological contrast between Romance and Germanic languages as verb-framed versus satellite-framed (Talmy 1985) forms the background for many empirical studies on L2 acquisition, the inconclusive picture to date calls for more differentiated, fine-grained analyses. The present study goes beyond explanations based on this typological contrast and takes into account the sources from which spatial concepts are mainly derived in order to shape the trajectory traced by the entity in motion when moving through space: the entity in V-languages versus features of the ground in S-languages. It investigates why advanced French learners of English and German have difficulty acquiring the use of spatial concepts typical of the L2s to shape the trajectory, although relevant concepts can be expressed in their L1. The analysis compares motion event descriptions, based on the same sets of video clips, of L1 speakers of the three languages to L1 French-L2 English and L1 French-L2 German speakers, showing that the learners do not fully acquire the use of L2-specific spatial concepts. We argue that encoded concepts derived from the entity in motion vs. the ground lead to a focus on different aspects of motion events, in accordance with their compatibility with these sources, and are difficult to restructure in L2 acquisition.

Abstract

Until recently, corpus studies of natural bilingual speech and, more specifically, codeswitching in bilingual speech have used a manual method of glossing, partof- speech tagging, and clause-splitting to prepare the data for analysis. In our article, we present innovative tools developed for the first large-scale corpus study of codeswitching triggered by cognates. A study of this size was only possible due to the automation of several steps, such as morpheme-by-morpheme glossing, splitting complex clauses into simple clauses, and the analysis of internal and external codeswitching through the use of database tables, algorithms, and a scripting language.

Abstract

Can children’s handedness influence how they represent abstract concepts like kindness and intelligence? Here we show that from an early age, right-handers associate rightward space more strongly with positive ideas and leftward space with negative ideas, but the opposite is true for left-handers. In one experiment, children indicated where on a diagram a preferred toy and a dispreferred toy should go. Right-handers tended to assign the preferred toy to a box on the right and the dispreferred toy to a box on the left. Left-handers showed the opposite pattern. In a second experiment, children judged which of two cartoon animals looked smarter (or dumber) or nicer (or meaner). Right-handers attributed more positive qualities to animals on the right, but left-handers to animals on the left. These contrasting associations between space and valence cannot be explained by exposure to language or cultural conventions, which consistently link right with good. Rather, right- and left-handers implicitly associated positive valence more strongly with the side of space on which they can act more fluently with their dominant hands. Results support the body-specificity hypothesis (Casasanto, 2009), showing that children with different kinds of bodies think differently in corresponding ways.

Abstract

Children begin developing turn-taking skills in infancy but take several years to fluidly integrate their growing knowledge of language into their turn-taking behavior. In two eye-tracking experiments, we measured children’s anticipatory gaze to upcoming responders while controlling linguistic cues to turn structure. In Experiment 1, we showed English and non-English conversations to English-speaking adults and children. In Experiment 2, we phonetically controlled lexicosyntactic and prosodic cues in English-only speech. Children spontaneously made anticipatory gaze switches by age two and continued improving through age six. In both experiments, children and adults made more anticipatory switches after hearing questions. Consistent with prior findings on adult turn prediction, prosodic information alone did not increase children’s anticipatory gaze shifts. But, unlike prior work with adults, lexical information alone was not sucient either—children’s performance was best overall with lexicosyntax and prosody together. Our findings support an account in which turn tracking and turn prediction emerge in infancy and then gradually become integrated with children’s online linguistic processing.

Abstract

Learning a specific skill during childhood may partly determine the functional organization of the adult brain. This hypothesis led us to study oral language processing in illiterate subjects who, for social reasons, had never entered school and had no knowledge of reading or writing. In a brain activation study using PET and statistical parametric mapping, we compared word and pseudoword repetition in literate and illiterate subjects. Our study confirms behavioural evidence of different phonological processing in illiterate subjects. During repetition of real words, the two groups performed similarly and activated similar areas of the brain. In contrast, illiterate subjects had more difficulty repeating pseudowords correctly and did not activate the same neural structures as literates. These results are consistent with the hypothesis that learning the written form of language (orthography) interacts with the function of oral language. Our results indicate that learning to read and write during childhood influences the functional organization of the adult human brain.

Abstract

Last year was the 150th anniversary of Paul Broca's landmark case report on speech disorder that paved the way for subsequent studies of cortical localization of higher cognitive functions. However, many complex functions rely on the activity of distributed networks rather than single cortical areas. Hence, it is important to understand how brain regions are linked within large-scale networks and to map lesions onto connecting white matter tracts. To facilitate this network approach we provide a synopsis of classical neurological syndromes associated with frontal, parietal, occipital, temporal and limbic lesions. A review of tractography studies in a variety of neuropsychiatric disorders is also included. The synopsis is accompanied by a new atlas of the human white matter connections based on diffusion tensor tractography freely downloadable on http://www.natbrainlab.com. Clinicians can use the maps to accurately identify the tract affected by lesions visible on conventional CT or MRI. The atlas will also assist researchers to interpret their group analysis results. We hope that the synopsis and the atlas by allowing a precise localization of white matter lesions and associated symptoms will facilitate future work on the functional correlates of human neural networks as derived from the study of clinical populations. Our goal is to stimulate clinicians to develop a critical approach to clinico-anatomical correlative studies and broaden their view of clinical anatomy beyond the cortical surface in order to encompass the dysfunction related to connecting pathways.

Abstract

The parietal lobe has a unique place in the human brain. Anatomically, it is at the crossroad between the frontal, occipital, and temporal lobes, thus providing a middle ground for multimodal sensory integration. Functionally, it supports higher cognitive functions that are characteristic of the human species, such as mathematical cognition, semantic and pragmatic aspects of language, and abstract thinking. Despite its importance, a comprehensive comparison of human and simian intraparietal networks is missing.

In this study, we used diffusion imaging tractography to reconstruct the major intralobar parietal tracts in twenty-one datasets acquired in vivo from healthy human subjects and eleven ex vivo datasets from five vervet and six macaque monkeys. Three regions of interest (postcentral gyrus, superior parietal lobule and inferior parietal lobule) were used to identify the tracts. Surface projections were reconstructed for both species and results compared to identify similarities or differences in tract anatomy (i.e., trajectories and cortical projections). In addition, post-mortem dissections were performed in a human brain.

The largest tract identified in both human and monkey brains is a vertical pathway between the superior and inferior parietal lobules. This tract can be divided into an anterior (supramarginal gyrus) and a posterior (angular gyrus) component in both humans and monkey brains. The second prominent intraparietal tract connects the postcentral gyrus to both supramarginal and angular gyri of the inferior parietal lobule in humans but only to the supramarginal gyrus in the monkey brain. The third tract connects the postcentral gyrus to the anterior region of the superior parietal lobule and is more prominent in monkeys compared to humans. Finally, short U-shaped fibres in the medial and lateral aspects of the parietal lobe were identified in both species. A tract connecting the medial parietal cortex to the lateral inferior parietal cortex was observed in the monkey brain only.

Our findings suggest a consistent pattern of intralobar parietal connections between humans and monkeys with some differences for those areas that have cytoarchitectonically distinct features in humans. The overall pattern of intraparietal connectivity supports the special role of the inferior parietal lobule in cognitive functions characteristic of humans.

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

We report on an eye-tracking study that investigated four-year-old Cantonese-speaking children's online processing of subject and object relative clauses (RCs). Children's eye-movements were recorded as they listened to RC structures identifying a unique referent (e.g. “Can you pick up the horse that pushed the pig?”). Two RC types, classifier (CL) and ge3 RCs, were tested in a between-participants design. The two RC types differ in their syntactic analyses and frequency of occurrence, providing an important point of comparison for theories of RC acquisition and processing. A permutation analysis showed that the two structures were processed differently: CL RCs showed a significant object-over-subject advantage, whereas ge3 RCs showed the opposite effect. This study shows that children can have different preferences even for two very similar RC structures within the same language, suggesting that syntactic processing preferences are shaped by the unique features of particular constructions both within and across different linguistic typologies.

Abstract

Linguistic adaptation is a phenomenon where language representations change in response to linguistic input. Adaptation can occur on multiple linguistic levels such as phonology (tuning of phonotactic constraints), words (repetition priming), and syntax (structural priming). The persistent nature of these adaptations suggests that they may be a form of implicit learning and connectionist models have been developed which instantiate this hypothesis. Research on implicit learning, however, has also produced evidence that explicit chunk knowledge is involved in the performance of these tasks. In this review, we examine how these interacting implicit and explicit processes may change our understanding of language learning and processing.

Abstract

Tense/aspect morphology on verbs is often thought to depend on event features like telicity, but it is not known how speakers identify these features in visual scenes. To examine this question, we asked Japanese speakers to describe computer-generated animations of simple actions with variation in visual features related to telicity. Experiments with adults and children found that they could use goal information in the animations to select appropriate past and progressive verb forms. They also produced a large number of different verb forms. To explain these findings, a deep-learning model of verb production from visual input was created that could produce a human-like distribution of verb forms. It was able to use visual cues to select appropriate tense/aspect morphology. The model predicted that video duration would be related to verb complexity, and past tense production would increase when it received the endpoint as input. These predictions were confirmed in a third study with Japanese adults. This work suggests that verb production could be tightly linked to visual heuristics that support the understanding of events.

Abstract

Objects in the world usually have names at different hierarchical levels (e.g., beagle, dog, animal). This research investigates adults' ability to use cross-situational statistics to simultaneously learn object labels at individual and category levels. The results revealed that adults were able to use co-occurrence information to learn hierarchical labels in contexts where the labels for individual objects and labels for categories were presented in completely separated blocks, in interleaved blocks, or mixed in the same trial. Temporal presentation schedules significantly affected the learning of individual object labels, but not the learning of category labels. Learners' subsequent generalization of category labels indicated sensitivity to the structure of statistical input.

Abstract

Messenger ribonucleic acids (RNAs) contain a large number of cis-regulatory RNA elements that function in many types of post-transcriptional regulation. These cis-regulatory elements are often characterized by conserved structures and/or sequences. Although some classes are well known, given the wide range of RNA-interacting proteins in eukaryotes, it is likely that many new classes of cis-regulatory elements are yet to be discovered. An approach to this is to use computational methods that have the advantage of analysing genomic data, particularly comparative data on a large scale. In this study, a set of structural discovery algorithms was applied followed by support vector machine (SVM) classification. We trained a new classification model (CisRNA-SVM) on a set of known structured cis-regulatory elements from 3′-untranslated regions (UTRs) and successfully distinguished these and groups of cis-regulatory elements not been strained on from control genomic and shuffled sequences. The new method outperformed previous methods in classification of cis-regulatory RNA elements. This model was then used to predict new elements from cross-species conserved regions of human 3′-UTRs. Clustering of these elements identified new classes of potential cis-regulatory elements. The model, training and testing sets and novel human predictions are available at: http://mRNA.otago.ac.nz/CisRNA-SVM.

Abstract

A significant proportion of children have unexplained problems acquiring proficient linguistic skills despite adequate intelligence and opportunity. Developmental language disorders are highly heritable with substantial societal impact. Molecular studies have begun to identify candidate loci, but much of the underlying genetic architecture remains undetermined. We performed whole-exome sequencing of 43 unrelated probands affected by severe specific language impairment, followed by independent validations with Sanger sequencing, and analyses of segregation patterns in parents and siblings, to shed new light on aetiology. By first focusing on a pre-defined set of known candidates from the literature, we identified potentially pathogenic variants in genes already implicated in diverse language-related syndromes, including ERC1, GRIN2A, and SRPX2. Complementary analyses suggested novel putative candidates carrying validated variants which were predicted to have functional effects, such as OXR1, SCN9A and KMT2D. We also searched for potential “multiple-hit” cases; one proband carried a rare AUTS2 variant in combination with a rare inherited haplotype affecting STARD9, while another carried a novel nonsynonymous variant in SEMA6D together with a rare stop-gain in SYNPR. On broadening scope to all rare and novel variants throughout the exomes, we identified biological themes that were enriched for such variants, including microtubule transport and cytoskeletal regulation.

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

Children adopted early in life into another linguistic community typically forget their birth language but retain, unaware, relevant linguistic knowledge that may facilitate (re)learning of birth-language patterns. Understanding the nature of this knowledge can shed light on how language is acquired. Here, international adoptees from Korea with Dutch as their current language, and matched Dutch-native controls, provided speech production data on a Korean consonantal distinction unlike any Dutch distinctions, at the outset and end of an intensive perceptual training. The productions, elicited in a repetition task, were identified and rated by Korean listeners. Adoptees' production scores improved significantly more across the training period than control participants' scores, and, for adoptees only, relative production success correlated significantly with the rate of learning in perception (which had, as predicted, also surpassed that of the controls). Of the adoptee group, half had been adopted at 17 months or older (when talking would have begun), while half had been prelinguistic (under six months). The former group, with production experience, showed no advantage over the group without. Thus the adoptees' retained knowledge of Korean transferred from perception to production and appears to be abstract in nature rather than dependent on the amount of experience.

Abstract

Until at least 6 mo of age, infants show good discrimination for familiar phonetic contrasts (i.e., those heard in the environmental language) and contrasts that are unfamiliar. Adult-like discrimination (significantly worse for nonnative than for native contrasts) appears only later, by 9–10 mo. This has been interpreted as indicating that infants have no knowledge of phonology until vocabulary development begins, after 6 mo of age. Recently, however, word recognition has been observed before age 6 mo, apparently decoupling the vocabulary and phonology acquisition processes. Here we show that phonological acquisition is also in progress before 6 mo of age. The evidence comes from retention of birth-language knowledge in international adoptees. In the largest ever such study, we recruited 29 adult Dutch speakers who had been adopted from Korea when young and had no conscious knowledge of Korean language at all. Half were adopted at age 3–5 mo (before native-specific discrimination develops) and half at 17 mo or older (after word learning has begun). In a short intensive training program, we observe that adoptees (compared with 29 matched controls) more rapidly learn tripartite Korean consonant distinctions without counterparts in their later-acquired Dutch, suggesting that the adoptees retained phonological knowledge about the Korean distinction. The advantage is equivalent for the younger-adopted and the older-adopted groups, and both groups not only acquire the tripartite distinction for the trained consonants but also generalize it to untrained consonants. Although infants younger than 6 mo can still discriminate unfamiliar phonetic distinctions, this finding indicates that native-language phonological knowledge is nonetheless being acquired at that age.

Abstract

Several studies have documented that international adoptees, who in early years have
experienced a change from a language used in their birth country to a new language
in an adoptive country, benefit from the limited early exposure to the birth language
when relearning that language’s sounds later in life. The adoptees’ relearning advantages
have been argued to be conferred by lasting birth-language knowledge obtained from
the early exposure. However, it is also plausible to assume that the advantages may
arise from adoptees’ superior ability to learn language sounds in general, as a result
of their unusual linguistic experience, i.e., exposure to multiple languages in sequence
early in life. If this is the case, then the adoptees’ relearning benefits should generalize
to previously unheard language sounds, rather than be limited to their birth-language
sounds. In the present study, adult Korean adoptees in the Netherlands and matched
Dutch-native controls were trained on identifying a Japanese length distinction to which
they had never been exposed before. The adoptees and Dutch controls did not differ
on any test carried out before, during, or after the training, indicating that observed
adoptee advantages for birth-language relearning do not generalize to novel, previously
unheard language sounds. The finding thus fails to support the suggestion that
birth-language relearning advantages may arise from enhanced ability to learn language
sounds in general conferred by early experience in multiple languages. Rather, our
finding supports the original contention that such advantages involve memory traces
obtained before adoption

Abstract

Koriat (1981) demonstrated that an association from the target to a preceding prime, in the absence of an association from the prime to the target, facilitates lexical decision and referred to this effect as "backward priming". Backward priming is of relevance, because it can provide information about the mechanism underlying semantic priming effects. Following Neely (1991), we distinguish three mechanisms of priming: spreading activation, expectancy, and semantic matching/integration. The goal was to determine which of these mechanisms causes backward priming, by assessing effects of backward priming on a language-relevant ERP component, the N400, and reaction time (RT). Based on previous work, we propose that the N400 priming effect reflects expectancy and semantic matching/integration, but in contrast with RT does not reflect spreading activation. Experiment 1 shows a backward priming effect that is qualitatively similar for the N400 and RT in a lexical decision task. This effect was not modulated by an ISI manipulation. Experiment 2 clarifies that the N400 backward priming effect reflects genuine changes in N400 amplitude and cannot be ascribed to other factors. We will argue that these backward priming effects cannot be due to expectancy but are best accounted for in terms of semantic matching/integration.

Abstract

Background. Facial emotion recognition deficits are common after moderate-severe traumatic brain injury (TBI) and linked to poor social outcomes. We examine whether emotion recognition deficits extend to facial expressions depicted by emoji.
Methods. Fifty-one individuals with moderate-severe TBI (25 female) and fifty-one neurotypical peers (26 female) viewed photos of human faces and emoji. Participants selected the best-fitting label from a set of basic emotions (anger, disgust, fear, sadness, neutral, surprise, happy) or social emotions (embarrassed, remorseful, anxious, neutral, flirting, confident, proud).
Results. We analyzed the likelihood of correctly labeling an emotion by group (neurotypical, TBI), stimulus condition (basic faces, basic emoji, social emoji), sex (female, male), and their interactions. Participants with TBI did not significantly differ from neurotypical peers in overall emotion labeling accuracy. Both groups had poorer labeling accuracy for emoji compared to faces. Participants with TBI (but not neurotypical peers) had poorer accuracy for labeling social emotions depicted by emoji compared to basic emotions depicted by emoji. There were no effects of participant sex.
Discussion. Because emotion representation is more ambiguous in emoji than human faces, studying emoji use and perception in TBI is an important consideration for understanding functional communication and social participation after brain injury.

Abstract

When we talk, we often make hand movements called gestures at the same time. Although just about everyone gestures when they talk, we usually do not even notice the gestures. Our hand gestures play an important role in helping us learn and remember! When we see other people gesturing when they talk—or when we gesture when we talk ourselves—we are more likely to remember the information being talked about than if gestures were not involved. Our hand gestures can even indicate when we are ready to learn new things! In this article, we explain how gestures can help learning. To investigate this, we studied children learning a new mathematical concept called equivalence. We hope that this article will help you notice when you, your friends and family, and your teachers are gesturing, and that it will help you understand how those gestures can help people learn.

Abstract

Purpose

Real-world communication is situated in rich multimodal contexts, containing speech and gesture. Speakers often convey unique information in gesture that is not present in the speech signal (e.g., saying “He searched for a new recipe” while making a typing gesture). We examine the narrative retellings of participants with and without moderate-severe traumatic brain injury across three timepoints over two online Zoom sessions to investigate whether people with TBI can integrate information from co-occurring speech and gesture and if information from gesture persists across delays.

Methods

60 participants with TBI and 60 non-injured peers watched videos of a narrator telling four short stories. On key details, the narrator produced complementary gestures that conveyed unique information. Participants retold the stories at three timepoints: immediately after, 20-min later, and one-week later. We examined the words participants used when retelling these key details, coding them as a Speech Match (e.g., “He searched for a new recipe”), a Gesture Match (e.g., “He searched for a new recipe online), or Other (“He looked for a new recipe”). We also examined whether participants produced representative gestures themselves when retelling these details.

Results

Despite recalling fewer story details, participants with TBI were as likely as non-injured peers to report information from gesture in their narrative retellings. All participants were more likely to report information from gesture and produce representative gestures themselves one-week later compared to immediately after hearing the story.

Conclusion

We demonstrated that speech-gesture integration is intact after TBI in narrative retellings. This finding has exciting implications for the utility of gesture to support comprehension and memory after TBI and expands our understanding of naturalistic multimodal language processing in this population.

Abstract

Impaired facial affect recognition is common after traumatic brain injury (TBI) and linked to poor social outcomes. We explored whether perception of emotions depicted by emoji is also impaired after TBI. Fifty participants with TBI and 50 non-injured peers generated free-text labels to describe emotions depicted by emoji and rated their levels of valence and arousal on nine-point rating scales. We compared how the two groups’ valence and arousal ratings were clustered and examined agreement in the words participants used to describe emoji. Hierarchical clustering of affect ratings produced four emoji clusters in the non-injured group and three emoji clusters in the TBI group. Whereas the non-injured group had a strongly positive and a moderately positive cluster, the TBI group had a single positive valence cluster, undifferentiated by arousal. Despite differences in cluster numbers, hierarchical structures of the two groups’ emoji ratings were significantly correlated. Most emoji had high agreement in the words participants with and without TBI used to describe them. Participants with TBI perceived emoji similarly to non-injured peers, used similar words to describe emoji, and rated emoji similarly on the valence dimension. Individuals with TBI showed small differences in perceived arousal for a minority of emoji. Overall, results suggest that basic recognition processes do not explain challenges in computer-mediated communication reported by adults with TBI. Examining perception of emoji in context by people with TBI is an essential next step for advancing our understanding of functional communication in computer-mediated contexts after brain injury.

Abstract

Expectancy mechanisms are routinely used by the cognitive system in stimulus processing and in anticipation of appropriate responses. Electrophysiology research has documented negative shifts of brain activity when expectancies are violated within a local stimulus context (e.g., reading an implausible word in a sentence) or more globally between consecutive stimuli (e.g., a narrative of images with an incongruent end). In this EEG study, we examine the interaction between expectancies operating at the level of stimulus plausibility and at more global level of contextual congruency to provide evidence for, or against, a disassociation of the underlying processing mechanisms. We asked participants to verify the congruency of pairs of cross-modal stimuli (a sentence and a scene), which varied in plausibility. ANOVAs on ERP amplitudes in selected windows of interest show that congruency violation has longer-lasting (from 100 to 500 ms) and more widespread effects than plausibility violation (from 200 to 400 ms). We also observed critical interactions between these factors, whereby incongruent and implausible pairs elicited stronger negative shifts than their congruent counterpart, both early on (100–200 ms) and between 400–500 ms. Our results suggest that the integration mechanisms are sensitive to both global and local effects of expectancy in a modality independent manner. Overall, we provide novel insights into the interdependence of expectancy during meaning integration of cross-modal stimuli in a verification task

Abstract

Recent game-theoretic simulation and analytical models have demonstrated that cooperative strategies mediated by indicators of cooperative potential, or “tags,” can invade, spread, and resist invasion by noncooperators across a range of population-structure and cost-benefit scenarios. The plausibility of these models is potentially relevant for human evolutionary accounts insofar as humans possess some phenotypic trait that could serve as a reliable tag. Linguistic markers, such as accent and dialect, have frequently been either cursorily defended or promptly dismissed as satisfying the criteria of a reliable and evolutionarily viable tag. This paper integrates evidence from a range of disciplines to develop and assess the claim that speech accent mediated the evolution of tag-based cooperation in humans. Existing evidence warrants the preliminary conclusion that accent markers meet the demands of an evolutionarily viable tag and potentially afforded a cost-effective solution to the challenges of maintaining viable cooperative relationships in diffuse, regional social networks.

Abstract

Common wisdom has it that Buddhism enhances compassion and self-other integration. We put this assumption to empirical test by comparing practicing Taiwanese Buddhists with well-matched atheists. Buddhists showed more evidence of self-other integration in the social Simon task, which assesses the degree to which people co-represent the actions of a coactor. This suggests that self-other integration and task co-representation vary as a function of religious practice.

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

Individual alpha frequency (IAF) is a promising electrophysiological marker of interindividual differences in cognitive function. IAF has been linked with trait-like differences in information processing and general intelligence, and provides an empirical basis for the definition of individualized frequency bands. Despite its widespread application, however, there is little consensus on the optimal method for estimating IAF, and many common approaches are prone to bias and inconsistency. Here, we describe an automated strategy for deriving two of the most prevalent IAF estimators in the literature: peak alpha frequency (PAF) and center of gravity (CoG). These indices are calculated from resting-state power spectra that have been smoothed using a Savitzky-Golay filter (SGF). We evaluate the performance characteristics of this analysis procedure in both empirical and simulated EEG data sets. Applying the SGF technique to resting-state data from n = 63 healthy adults furnished 61 PAF and 62 CoG estimates. The statistical properties of these estimates were consistent with previous reports. Simulation analyses revealed that the SGF routine was able to reliably extract target alpha components, even under relatively noisy spectral conditions. The routine consistently outperformed a simpler method of automated peak detection that did not involve spectral smoothing. The SGF technique is fast, open source, and available in two popular programming languages (MATLAB, Python), and thus can easily be integrated within the most popular M/EEG toolsets (EEGLAB, FieldTrip, MNE-Python). As such, it affords a convenient tool for improving the reliability and replicability of future IAF-related research.

Abstract

Comprehenders predict what a speaker is likely to say when listening to non-native (L2) and native (L1) utterances. But what are the characteristics of L2 prediction, and how does it relate to L1 prediction? We addressed this question in a visual-world eye-tracking experiment, which tested when L2 English comprehenders integrated perspective into their predictions. Male and female participants listened to male and female speakers producing sentences (e.g., I would like to wear the nice…) about stereotypically masculine (target: tie; distractor: drill) and feminine (target: dress; distractor: hairdryer) objects. Participants predicted associatively, fixating objects semantically associated with critical verbs (here, the tie and the dress). They also predicted stereotypically consistent objects (e.g., the tie rather than the dress, given the male speaker). Consistent predictions were made later than associative predictions, and were delayed for L2 speakers relative to L1 speakers. These findings suggest prediction involves both automatic and non-automatic stages.

Abstract

During conversation, interlocutors rapidly switch between speaker and listener
roles and take turns at talk. How do they achieve such fine coordination?
Most research has concentrated on the role of prediction, but listeners
must also prepare a response in advance (assuming they wish to respond)
and articulate this response at the appropriate moment. Such mechanisms
may overlap with the processes of comprehending the speaker’s incoming
turn and predicting its end. However, little is known about the stages of
response preparation and production. We discuss three questions pertaining
to such stages: (1) Do listeners prepare their own response in advance?,
(2) Can listeners buffer their prepared response?, and (3) Does buffering
lead to interference with concurrent comprehension? We argue that fine
coordination requires more than just an accurate prediction of the interlocutor’s
incoming turn: Listeners must also simultaneously prepare their own
response.

Abstract

During conversation, there is often little gap between interlocutors’ utterances. In two pairs of experiments, we manipulated the content predictability of yes/no questions to investigate whether listeners achieve such coordination by (i) preparing a response as early as possible or (ii) predicting the end of the speaker’s turn. To assess these two mechanisms, we varied the participants’ task: They either pressed a button when they thought the question was about to end (Experiments 1a and 2a), or verbally answered the questions with either yes or no (Experiments 1b and 2b). Predictability effects were present when participants had to prepare a verbal response, but not when they had to predict the turn-end. These findings suggest content prediction facilitates turn-taking because it allows listeners to prepare their own response early, rather than because it helps them predict when the speaker will reach the end of their turn.

Abstract

Word frequency plays a key role in theories of lexical access, which assume that the word frequency effect (WFE, faster access to high-frequency than low-frequency words) occurs as a result of differences in the representation and processing of the words. In a seminal paper, Jescheniak and Levelt (1994) proposed that the WFE arises during the retrieval of word forms, rather than the retrieval of their syntactic representations (their lemmas) or articulatory commands. An important part of Jescheniak and Levelt's argument was that they found a stable WFE in a picture naming task, which requires complete lexical access, but not in a gender decision task, which only requires access to the words' lemmas and not their word forms. We report two attempts to replicate this pattern, one with new materials, and one with Jescheniak and Levelt's orginal pictures. In both studies we found a strong WFE when the pictures were shown for the first time, but much weaker effects on their second and third presentation. Importantly these patterns were seen in both the picture naming and the gender decision tasks, suggesting that either word frequency does not exclusively affect word form retrieval, or that the gender decision task does not exclusively tap lemma access.

Abstract

Although previous research has demonstrated that language comprehension can be egocentric, there is little evidence for egocentricity during prediction. In particular, comprehenders do not appear to predict egocentrically when the context makes it clear what the speaker is likely to refer to. But do comprehenders predict egocentrically when the context does not make it clear? We tested this hypothesis using a visual-world eye-tracking paradigm, in which participants heard sentences containing the gender-neutral pronoun They (e.g. They would like to wear…) while viewing four objects (e.g. tie, dress, drill, hairdryer). Two of these objects were plausible targets of the verb (tie and dress), and one was stereotypically compatible with the participant's gender (tie if the participant was male; dress if the participant was female). Participants rapidly fixated targets more than distractors, but there was no evidence that participants ever predicted egocentrically, fixating objects stereotypically compatible with their own gender. These findings suggest that participants do not fall back on their own egocentric perspective when predicting, even when they know that context does not make it clear what the speaker is likely to refer to.

Abstract

The ABCA4 gene is the most frequently mutated Mendelian retinopathy-associated gene. Biallelic variants lead to a variety of phenotypes, however, for thousands of cases the underlying variants remain unknown. Here, we aim to shed further light on the missing heritability of ABCA4-associated retinopathy by analyzing a large cohort of macular dystrophy probands. A total of 858 probands were collected from 26 centers, of whom 722 carried no or one pathogenic ABCA4 variant while 136 cases carried two ABCA4 alleles, one of which was a frequent mild variant, suggesting that deep-intronic variants (DIVs) or other cis-modifiers might have been missed. After single molecule molecular inversion probes (smMIPs)-based sequencing of the complete 128-kb ABCA4 locus, the effect of putative splice variants was assessed in vitro by midigene splice assays in HEK293T cells. The breakpoints of copy number variants (CNVs) were determined by junction PCR and Sanger sequencing. ABCA4 sequence analysis solved 207/520 (39.8%) naïve or unsolved cases and 70/202 (34.7%) monoallelic cases, while additional causal variants were identified in 54/136 (39.7%) of probands carrying two variants. Seven novel DIVs and six novel non-canonical splice site variants were detected in a total of 35 alleles and characterized, including the c.6283-321C>G variant leading to a complex splicing defect. Additionally, four novel CNVs were identified and characterized in five alleles. These results confirm that smMIPs-based sequencing of the complete ABCA4 gene provides a cost-effective method to genetically solve retinopathy cases and that several rare structural and splice altering defects remain undiscovered in STGD1 cases.

Abstract

Past events like fluctuations in population size and post-glacial colonization processes may influence the relative importance of genetic drift, migration and selection when determining the present day patterns of genetic variation. We disentangle how drift, selection and migration shape neutral and adaptive genetic variation in 12 moor frog populations along a 1700 km latitudinal gradient. We studied genetic differentiation and variation at a MHC exon II locus and a set of 18 microsatellites.
Results

Using outlier analyses, we identified the MHC II exon 2 (corresponding to the β-2 domain) locus and one microsatellite locus (RCO8640) to be subject to diversifying selection, while five microsatellite loci showed signals of stabilizing selection among populations. STRUCTURE and DAPC analyses on the neutral microsatellites assigned populations to a northern and a southern cluster, reflecting two different post-glacial colonization routes found in previous studies. Genetic variation overall was lower in the northern cluster. The signature of selection on MHC exon II was weaker in the northern cluster, possibly as a consequence of smaller and more fragmented populations.
Conclusion

Our results show that historical demographic processes combined with selection and drift have led to a complex pattern of differentiation along the gradient where some loci are more divergent among populations than predicted from drift expectations due to diversifying selection, while other loci are more uniform among populations due to stabilizing selection. Importantly, both overall and MHC genetic variation are lower at northern latitudes. Due to lower evolutionary potential, the low genetic variation in northern populations may increase the risk of extinction when confronted with emerging pathogens and climate change.

Abstract

In three experiments, listeners detected vowel or consonant targets in lists of CV syllables constructed from five vowels and five consonants. Responses were faster in a predictable context (e.g., listening for a vowel target in a list of syllables all beginning with the same consonant) than in an unpredictable context (e.g., listening for a vowel target in a list of syllables beginning with different consonants). In Experiment 1, the listeners’ native language was Dutch, in which vowel and consonant repertoires are similar in size. The difference between predictable and unpredictable contexts was comparable for vowel and consonant targets. In Experiments 2 and 3, the listeners’ native language was Spanish, which has four times as many consonants as vowels; here effects of an unpredictable consonant context on vowel detection were significantly greater than effects of an unpredictable vowel context on consonant detection. This finding suggests that listeners’ processing of phonemes takes into account the constitution of their language’s phonemic repertoire and the implications that this has for contextual variability.

Abstract

The extent to which languages share properties reflecting the non-linguistic constraints of the speakers who speak them is key to the debate regarding the relationship between language and cognition. A critical case is spatial communication, where it has been argued that semantic universals should exist, if anywhere. Here, using an experimental paradigm able to separate variation within a language from variation between languages, we tested the use of spatial demonstratives—the most fundamental and frequent spatial terms across languages. In n = 874 speakers across 29 languages, we show that speakers of all tested languages use spatial demonstratives as a function of being able to reach or act on an object being referred to. In some languages, the position of the addressee is also relevant in selecting between demonstrative forms. Commonalities and differences across languages in spatial communication can be understood in terms of universal constraints on action shaping spatial language and cognition.

Abstract

When speaking to infants, adults often produce speech that differs systematically from that directed to other adults. In order to quantify the acoustic properties of this speech style across a wide variety of languages and cultures, we extracted results from empirical studies on the acoustic features of infant-directed speech (IDS). We analyzed data from 88 unique studies (734 effect sizes) on the following five acoustic parameters that have been systematically examined in the literature: i) fundamental frequency (fo), ii) fo variability, iii) vowel space area, iv) articulation rate, and v) vowel duration. Moderator analyses were conducted in hierarchical Bayesian robust regression models in order to examine how these features change with infant age and differ across languages, experimental tasks and recording environments. The moderator analyses indicated that fo, articulation rate, and vowel duration became more similar to adult-directed speech (ADS) over time, whereas fo variability and vowel space area exhibited stability throughout development. These results point the way for future research to disentangle different accounts of the functions and learnability of IDS by conducting theory-driven comparisons among different languages and using computational models to formulate testable predictions.

Abstract

A recent debate in the morphological literature concerns the status of derivational affixes. While some linguists (Marantz 1997, 2001; Marvin 2003) consider derivational affixes a type of functional morpheme that realizes a categorial head, others (Lowenstamm 2015; De Belder 2011) argue that derivational affixes are roots. Our proposal, which finds its empirical basis in a study of Dutch derivational affixes, takes a middle position. We argue that there are two types of derivational affixes: some that are roots (i.e. lexical morphemes) and others that are categorial heads (i.e. functional morphemes). Affixes that are roots show ‘flexible’ categorial behavior, are subject to ‘lexical’ phonological rules, and may trigger idiosyncratic meanings. Affixes that realize categorial heads, on the other hand, are categorially rigid, do not trigger ‘lexical’ phonological rules nor allow for idiosyncrasies in their interpretation.

Abstract

In most of the world, people have regular exposure to multiple accents. Therefore, learning to quickly process accented speech is a prerequisite to successful communication. In this paper, we examine work on the perception of accented speech across the lifespan, from early infancy to late adulthood. Unfamiliar accents initially impair linguistic processing by infants, children, younger adults, and older adults, but listeners of all ages come to adapt to accented speech. Emergent research also goes beyond these perceptual abilities, by assessing links with production and the relative contributions of linguistic knowledge and general cognitive skills. We conclude by underlining points of convergence across ages, and the gaps left to face in future work.

Abstract

Researchers have struggled to obtain a clear account of the evolution of prosocial behaviour despite a great deal of recent effort. The aim of this review is to take a brief step back from addressing the question of evolutionary origins of prosocial behaviour in order to identify contextual factors that are contributing to variation in the expression of prosocial behaviour and hindering progress towards identifying phylogenetic patterns. Most available data come from the Primate Order, and the choice of contextual factors to consider was informed by theory and practice, including the nature of the relationship between the potential donor and recipient, the communicative behaviour of the recipients, and features of the prosocial task including whether rewards are visible and whether the prosocial choice creates an inequity between actors. Conclusions are drawn about the facilitating or inhibiting impact of each of these factors on the expression of prosocial behaviour, and areas for future research are highlighted. Acknowledging the impact of these contextual features on the expression of prosocial behaviours should stimulate new research into the proximate mechanisms that drive these effects, yield experimental designs that better control for potential influences on prosocial expression, and ultimately allow progress towards reconstructing the evolutionary origins of prosocial behaviour.

Abstract

The social factors that influence cooperation have remained largely uninvestigated but have the potential to explain much of the variation in cooperative behavior observed in the natural world. We show here that certain dimensions of the social environment, namely the size of the social group, the degree of social tolerance expressed, the structure of the dominance hierarchy, and the patterns of dispersal, may influence the emergence and stability of cooperation in predictable ways. Furthermore, the social environment experienced by a species over evolutionary time will have shaped their cognition to provide certain strengths and strategies that are beneficial in their species‟ social world. These cognitive adaptations will in turn impact the likelihood of cooperating in a given social environment. Experiments with one primate species, the cottontop tamarin, illustrate how social dynamics may influence emergence and stability of cooperative behavior in this species. We then take a more general viewpoint and argue that the hypotheses presented here require further experimental work and the addition of quantitative modeling to obtain a better understanding of how social dynamics influence the emergence and stability of cooperative behavior in complex systems. We conclude by pointing out subsequent specific directions for models and experiments that will allow relevant advances in the understanding of the emergence of cooperation.

Abstract

A large amount of variability exists across human brains; revealed initially on a small scale by postmortem studies and,
more recently, on a larger scale with the advent of neuroimaging. Here we compared structural variability between human
and macaque monkey brains using grey and white matter magnetic resonance imaging measures. The monkey brain was
overall structurally as variable as the human brain, but variability had a distinct distribution pattern, with some key areas
showing high variability. We also report the first evidence of a relationship between anatomical variability and evolutionary
expansion in the primate brain. This suggests a relationship between variability and stability, where areas of low variability
may have evolved less recently and have more stability, while areas of high variability may have evolved more recently and
be less similar across individuals. We showed specific differences between the species in key areas, including the amount of
hemispheric asymmetry in variability, which was left-lateralized in the human brain across several phylogenetically recent
regions. This suggests that cerebral variability may be another useful measure for comparison between species and may add
another dimension to our understanding of evolutionary mechanisms.

Abstract

Word-initial CVC syllables are detected faster in words beginning consonant-vowel-consonant-vowel (CVCV-) than in words beginning consonant-vowel-consonant-consonant (CVCC-). This effect was reported independently by M. Taft and G. Hambly (1985, Journal of Memory and Language, 24, 320–335) and by A. Cutler, J. Mehler, D. Norris, and J. Segui (1986, Journal of Memory and Language, 25, 385–400). Taft and Hambly explained the effect in terms of lexical factors. This explanation cannot account for Cutler et al.'s results, in which the effect also appeared with nonwords and foreign words. Cutler et al. suggested that CVCV-sequences might simply be easier to perceive than CVCC-sequences. The present study confirms this suggestion, and explains it as a reflection of listener expectations constructed on the basis of distributional characteristics of the language.

Abstract

To examine whether lexically stored knowledge about spelling influences phoneme evaluation, we conducted three experiments with a low-level phonetic judgement task: phoneme goodness rating. In each experiment, listeners heard phonetic tokens varying along a continuum centred on /s/, occurring finally in isolated word or nonword tokens. An effect of spelling appeared in Experiment 1: Native English speakers’ goodness ratings for the best /s/ tokens were significantly higher in words spelled with S (e.g., bless) than in words spelled with C (e.g., voice). No such difference appeared when nonnative speakers rated the same materials in Experiment 2, indicating that the difference could not be due to acoustic characteristics of the S- versus C-words. In Experiment 3, nonwords with lexical neighbours consistently spelled with S (e.g., pless) versus with C (e.g., floice) failed to elicit orthographic neighbourhood effects; no significant difference appeared in native English speakers’ ratings for the S-consistent versus the C-consistent sets. Obligatory influence of lexical knowledge on phonemic processing would have predicted such neighbourhood effects; the findings are thus better accommodated by models in which phonemic decisions draw strategically upon lexical information.

Abstract

Because stress can occur in any position within an Eglish word, lexical prosody could serve as a minimal distinguishing feature between pairs of words. However, most pairs of English words with stress pattern opposition also differ vocalically: OBject an obJECT, CONtent and content have different vowels in their first syllables an well as different stress patters. To test whether prosodic information is made use in auditory word recognition independently of segmental phonetic information, it is necessary to examine pairs like FORbear – forBEAR of TRUSty – trusTEE, semantically unrelated words which echbit stress pattern opposition but no segmental difference. In a cross-modal priming task, such words produce the priming effects characteristic of homophones, indicating that lexical prosody is not used in the same was as segmental structure to constrain lexical access.

Abstract

The way we listen to spoken language is tailored to the specific benefit of native-language speech input. Listening to speech in non-native languages can be significantly hindered by this native bias. Is it possible to determine the degree to which a listener is listening in a native-like manner? Promising indications of how this question may be tackled are provided by new research findings concerning the great flexibility that characterises listening to the L1, in online adjustment of phonetic category boundaries for adaptation across talkers, and in modulation of lexical dynamics for adjustment across listening conditions. This flexibility pays off in many dimensions, including listening in noise, adaptation across dialects, and identification of voices. These findings further illuminate the robustness and flexibility of native listening, and potentially point to ways in which we might begin to assess degrees of ‘native-likeness’ in this skill.

Abstract

Two bodies of recent research from experimental psycholinguistics are summarised, each of which is centred upon a concept from phonology: LEXICAL STRESS and the SYLLABLE. The evidence indicates that neither construct plays a role in prelexical representations during speech recog- nition. Both constructs, however, are well supported by other performance evidence. Testing phonological claims against performance evidence from psycholinguistics can be difficult, since the results of studies designed to test processing models are often of limited relevance to phonological theory.

Abstract

Studies of spoken-word recognition have revealed that competition from embedded words differs in strength as a function of where in the carrier word the embedded word is found and have further shown embedding patterns to be skewed such that embeddings in initial position in carriers outnumber embeddings in final position. Lexico-statistical analyses show that this skew is highly attenuated in Japanese, a noninflectional language. Comparison of the extent of the asymmetry in the three Germanic languages English, Dutch, and German allows the source to be traced to a combination of suffixal morphology and vowel reduction in unstressed syllables.

Abstract

Four studies are reported in which young children’s response time to detect word targets was measured. Children under about six years of age did not show response time advantage for accented target words which adult listeners show. When semantic focus of the target word was manipulated independently of accent, children of about five years of age showed an adult-like response time advantage for focussed targets, but children younger than five did not. Id is argued that the processing advantage for accented words reflect the semantic role of accent as an expression of sentence focus. Processing advantages for accented words depend on the prior development of representations of sentence semantic structure, including the concept of focus. The previous literature on the development of prosodic competence shows an apparent anomaly in that young children’s productive skills appear to outstrip their receptive skills; however, this anomaly disappears if very young children’s prosody is assumed to be produced without an underlying representation of the relationship between prosody and semantics.

Abstract

Studies of human speech processing have provided evidence for a segmentation strategy in the perception of continuous speech, whereby a word boundary is postulated, and a lexical access procedure initiated, at each metrically strong syllable. The likely success of this strategy was here estimated against the characteristics of the English vocabulary. Two computerized dictionaries were found to list approximately three times as many words beginning with strong syllables (i.e. syllables containing a full vowel) as beginning with weak syllables (i.e. syllables containing a reduced vowel). Consideration of frequency of lexical word occurrence reveals that words beginning with strong syllables occur on average more often than words beginning with weak syllables. Together, these findings motivate an estimate for everyday speech recognition that approximately 85% of lexical words (i.e. excluding function words) will begin with strong syllables. This estimate was tested against a corpus of 190 000 words of spontaneous British English conversion. In this corpus, 90% of lexical words were found to begin with strong syllables. This suggests that a strategy of postulating word boundaries at the onset of strong syllables would have a high success rate in that few actual lexical word onsets would be missed.

Abstract

Speech segmentation procedures may differ in speakers of different languages. Earlier work based on French speakers listening to French words suggested that the syllable functions as a segmentation unit in speech processing. However, while French has relatively regular and clearly bounded syllables, other languages, such as English, do not. No trace of syllabifying segmentation was found in English listeners listening to English words, French words, or nonsense words. French listeners, however, showed evidence of syllabification even when they were listening to English words. We conclude that alternative segmentation routines are available to the human language processor. In some cases speech segmentation may involve the operation of more than one procedure

Abstract

We show that Atkinson’s (Reports, 15 April 2011, p. 346) intriguing proposal—that global
linguistic diversity supports a single language origin in Africa—is an artifact of using suboptimal
data, biased methodology, and unjustified assumptions. We criticize his approach using more
suitable data, and we additionally provide new results suggesting a more complex scenario for the
emergence of global linguistic diversity.

Abstract

Evidence from certain geographical areas links lymphomas of the ocular adnexa marginal zone B-cell lymphomas (OAMZL) with Chlamydophila psittaci (Cp) infection, suggesting that lymphoma development is dependent upon chronic stimulation by persistent infections. Notwithstanding that, the actual immunopathogenetical mechanisms have not yet been elucidated. As in other B-cell lymphomas, insight into this issue, especially with regard to potential selecting ligands, could be provided by analysis of the immunoglobulin (IG) receptors of the malignant clones. To this end, we studied the molecular features of IGs in 44 patients with OAMZL (40% Cp-positive), identifying features suggestive of a pathogenic mechanism of autoreactivity. Herein, we show that lymphoma cells express a distinctive IG repertoire, with electropositive antigen (Ag)-binding sites, reminiscent of autoantibodies (auto-Abs) recognizing DNA. Additionally, five (11%) cases of OAMZL expressed IGs homologous with autoreactive Abs or IGs of patients with chronic lymphocytic leukemia, a disease known for the expression of autoreactive IGs by neoplastic cells. In contrast, no similarity with known anti-Chlamydophila Abs was found. Taken together, these results strongly indicate that OAMZL may originate from B cells selected for their capability to bind Ags and, in particular, auto-Ags. In OAMZL associated with Cp infection, the pathogen likely acts indirectly on the malignant B cells, promoting the development of an inflammatory milieu, where auto-Ags could be exposed and presented, driving proliferation and expansion of self-reactive B cells.

Abstract

The neural mechanism for selectively tuning in to a target speaker while tuning out the others in a multi-speaker situation (i.e., the cocktail-party effect) remains elusive. Here we addressed this issue by measuring brain activity simultaneously from a listener and from multiple speakers while they were involved in naturalistic conversations. Results consistently show selectively enhanced interpersonal neural synchronization (INS) between the listener and the attended speaker at left temporal–parietal junction, compared with that between the listener and the unattended speaker across different multi-speaker situations. Moreover, INS increases significantly prior to the occurrence of verbal responses, and even when the listener’s brain activity precedes that of the speaker. The INS increase is independent of brain-to-speech synchronization in both the anatomical location and frequency range. These findings suggest that INS underlies the selective process in a multi-speaker situation through neural predictions at the content level but not the sensory level of speech.

Abstract

Speech-in-speech perception can be challenging because the processing of competing acoustic and linguistic information leads to informational masking. Here, a method is proposed to isolate the linguistic component of informational masking while keeping the distractor's acoustic information unchanged. Participants performed a dichotic listening cocktail-party task before and after training on 4-band noise-vocoded sentences that became intelligible through the training. Distracting noise-vocoded speech interfered more with target speech comprehension after training (i.e., when intelligible) than before training (i.e., when unintelligible) at −3 dB SNR. These findings confirm that linguistic and acoustic information have distinct masking effects during speech-in‐speech comprehension

Abstract

The Battery for the Assessment of Auditory Sensorimotor and Timing Abilities (BAASTA) is a new tool for the systematic assessment of perceptual and sensorimotor timing skills. It spans a broad range of timing skills aimed at differentiating individual timing profiles. BAASTA consists of sensitive time perception and production tasks. Perceptual tasks include duration discrimination, anisochrony detection (with tones and music), and a version of the Beat Alignment Task. Perceptual thresholds for duration discrimination and anisochrony detection are estimated with a maximum likelihood procedure (MLP) algorithm. Production tasks use finger tapping and include unpaced and paced tapping (with tones and music), synchronization-continuation, and adaptive tapping to a sequence with a tempo change. BAASTA was tested in a proof-of-concept study with 20 non-musicians (Experiment 1). To validate the results of the MLP procedure, less widespread than standard staircase methods, three perceptual tasks of the battery (duration discrimination, anisochrony detection with tones, and with music) were further tested in a second group of non-musicians using 2 down / 1 up and 3 down / 1 up staircase paradigms (n = 24) (Experiment 2). The results show that the timing profiles provided by BAASTA allow to detect cases of timing/rhythm disorders. In addition, perceptual thresholds yielded by the MLP algorithm, although generally comparable to the results provided by standard staircase, tend to be slightly lower. In sum, BAASTA provides a comprehensive battery to test perceptual and sensorimotor timing skills, and to detect timing/rhythm deficits.

Abstract

The morphosyntactic paradigm of an inflected word can influence isolated word recognition, but its role in multiple-word phrasal integration is less clear. We examined the electrophysiological response to adjectives in short German prepositional phrases to evaluate whether strong and weak forms of the adjective show a differential response, and whether paradigm variables are related to this response. Twenty native German speakers classified serially presented phrases as grammatically correct or not while the electroencephalogram (EEG) was recorded. A functional mixed effects model of the response to grammatically correct trials revealed a differential response to strong and weak forms of the adjectives. This response difference depended on whether the preceding preposition imposed accusative or dative case. The lexically conditioned information content of the adjectives modulated a later interval of the response. The results indicate that grammatical context modulates the response to morphosyntactic information content, and lends support to the role of paradigm structure in integrative phrasal processing.

Abstract

Language is the best example of a cultural evolutionary system, able to retain a phylogenetic signal over many thousands of years. The temporal stability (conservatism) of basic vocabulary is relatively well understood, but the stability of the structural properties of language (phonology, morphology, syntax) is still unclear. Here we report an extensive Bayesian phylogenetic investigation of the structural stability of numerous features across many language families and we introduce a novel method for analyzing the relationships between the “stability profiles” of language families. We found that there is a strong universal component across language families, suggesting the existence of universal linguistic, cognitive and genetic constraints. Against this background, however, each language family has a distinct stability profile, and these profiles cluster by geographic area and likely deep genealogical relationships. These stability profiles reveal, for example, the ancient historical relationships between the Siberian and American language families, presumed to be separated by at least 12,000 years. Thus, such higher-level properties of language seen as an evolutionary system might allow the investigation of ancient connections between languages and shed light on the peopling of the world.

Abstract

One of the best-known types of non-independence between languages is caused by genealogical relationships due to descent from a common ancestor. These can be represented by (more or less resolved and controversial) language family trees. In theory, one can argue that language families should be built through the strict application of the comparative method of historical linguistics, but in practice this is not always the case, and there are several proposed classifications of languages into language families, each with its own advantages and disadvantages. A major stumbling block shared by most of them is that they are relatively difficult to use with computational methods, and in particular with phylogenetics. This is due to their lack of standardization, coupled with the general non-availability of branch length information, which encapsulates the amount of evolution taking place on the family tree. In this paper I introduce a method (and its implementation in R) that converts the language classifications provided by four widely-used databases (Ethnologue, WALS, AUTOTYP and Glottolog) intothe de facto Newick standard generally used in phylogenetics, aligns the four most used conventions for unique identifiers of linguistic entities (ISO 639-3, WALS, AUTOTYP and Glottocode), and adds branch length information from a variety of sources (the tree's own topology, an externally given numeric constant, or a distance matrix). The R scripts, input data and resulting Newick trees are available under liberal open-source licenses in a GitHub repository (https://github.com/ddediu/lgfam-newick), to encourage and promote the use of phylogenetic methods to investigate linguistic diversity and its temporal dynamics.

Abstract

Commentary on Cohen, E. (2012). The evolution of tag-based cooperation in humans: The case for accent. Current Anthropology, 53, 588-616. doi:10.1086/667654.

Abstract

Language is not a purely cultural phenomenon somehow isolated from its wider environment, and we may only understand its origins and evolution by seriously considering its embedding in this environment as well as its multimodal nature. By environment here we understand other aspects of culture (such as communication technology, attitudes towards language contact, etc.), of the physical environment (ultraviolet light incidence, air humidity, etc.), and of the biological infrastructure for language and speech. We are specifically concerned in this paper with the latter, in the form of the biases, constraints and affordances that the anatomy and physiology of the vocal tract create on speech and language. In a nutshell, our argument is that (a) there is an under-appreciated amount of inter-individual variation in vocal tract (VT) anatomy and physiology, (b) variation that is non-randomly distributed across populations, and that (c) results in systematic differences in phonetics and phonology between languages. Relevant differences in VT anatomy include the overall shape of the hard palate, the shape of the alveolar ridge, the relationship between the lower and upper jaw, to mention just a few, and our data offer a new way to systematically explore such differences and their potential impact on speech. These differences generate very small biases that nevertheless can be amplified by the repeated use and transmission of language, affecting language diachrony and resulting in cross-linguistic synchronic differences. Moreover, the same type of biases and processes might have played an essential role in the emergence and evolution of language, and might allow us a glimpse into the speech and language of extinct humans by, for example, reconstructing the anatomy of parts of their vocal tract from the fossil record and extrapolating the biases we find in present-day humans.

Abstract

Here we re-evaluate our 2013 paper on the antiquity of language (Dediu and Levinson, 2013) in the light of a surge of new information on human evolution in the last half million years. Although new genetic data suggest the existence of some cognitive differences between Neanderthals and modern humans — fully expected after hundreds of thousands of years of partially separate evolution, overall our claims that Neanderthals were fully articulate beings and that language evolution was gradual are further substantiated by the wealth of new genetic, paleontological and archeological evidence briefly reviewed here.

Abstract

This paper presents the first part of a guide for documenting and describing child language, child-directed language and socialization patterns in diverse languages and cultures. The guide is intended for anyone interested in working across child language and language documentation,
including, for example, field linguists and language documenters, community language workers, child language researchers or graduate students. We assume some basic familiarity with language documentation principles and methods, and, based on this, provide step-by-step suggestions for
collecting, analyzing and presenting child data. This first part of the guide focuses on constructing a sketch corpus that consists of minimally five hours of annotated and archived data and which documents communicative practices of children between the ages of 2 and 4.

Abstract

This paper presents the second part of a guide for documenting and describing child language, child-directed language and socialization patterns in diverse languages and cultures. The guide is intended for anyone interested in working across child language and language documentation,
including, for example, field linguists and language documenters, community language workers, child language researchers or graduate students. We assume some basic familiarity with language documentation principles and methods, and, based on this, provide step-by-step suggestions for
collecting, analyzing and presenting child data. This second part of the guide focuses on developing a child language acquisition sketch. It takes the sketch corpus as its basis (which was introduced in the first part of this guide), and presents a model for analyzing and describing the corpus data.

Abstract

In this article we investigate the relation between discourse markers and turn-transition strategies in face-to-face conversations and Instant Messaging (IM), that is, unplanned, real-time, text-based, computer-mediated communication. By means of a quantitative corpus study of utterances containing a discourse marker, we show that utterance-final discourse markers are used more often in IM than in face-to-face conversations. Moreover, utterance-final discourse markers are shown to occur more often at points of turn-transition compared with points of turn-maintenance in both types of conversation. From our results we conclude that the discourse markers in utterance-final position can function as a turn-transition mechanism, signaling that the turn is over and the floor is open to the hearer. We argue that this linguistic turn-taking strategy is essentially similar in face-to-face and IM communication. Our results add to the evidence that communication in IM is more like speech than like writing.

Abstract

Speakers choose a particular expression based on many factors, including availability of the referent in the perceptual context. We examined whether, when expressing referents, monolingual English- and Turkish-speaking children: (1) are sensitive to perceptual context, (2) express this sensitivity in language-specific ways, and (3) use co-speech gestures to specify referents that are underspecified. We also explored the mechanisms underlying children's sensitivity to perceptual context. Children described short vignettes to an experimenter under two conditions: The characters in the vignettes were present in the perceptual context (perceptual context); the characters were absent (no perceptual context). Children routinely used nouns in the no perceptual context condition, but shifted to pronouns (English-speaking children) or omitted arguments (Turkish-speaking children) in the perceptual context condition. Turkish-speaking children used underspecified referents more frequently than English-speaking children in the perceptual context condition; however, they compensated for the difference by using gesture to specify the forms. Gesture thus gives children learning structurally different languages a way to achieve comparable levels of specification while at the same time adhering to the referential expressions dictated by their language.

Abstract

Recurrent de novo variants in the TBR1 transcription factor are implicated in the etiology of sporadic autism spectrum disorders (ASD). Disruptions include missense variants located in the T-box DNA-binding domain and previous work has demonstrated that they disrupt TBR1 protein function. Recent screens of thousands of simplex families with sporadic ASD cases uncovered additional T-box variants in TBR1 but their etiological relevance is unclear. We performed detailed functional analyses of de novo missense TBR1 variants found in the T-box of ASD cases, assessing many aspects of protein function, including subcellular localization, transcriptional activity and protein-interactions. Only two of the three tested variants severely disrupted TBR1 protein function, despite in silico predictions that all would be deleterious. Furthermore, we characterized a putative interaction with BCL11A, a transcription factor that was recently implicated in a neurodevelopmental syndrome involving developmental delay and language deficits. Our findings enhance understanding of molecular functions of TBR1, as well as highlighting the importance of functional testing of variants that emerge from next-generation sequencing, to decipher their contributions to neurodevelopmental disorders like ASD.

Abstract

Abnormal prosody is a striking feature of the speech of those with Autism Spectrum Disorder (ASD), but previous reports suggest large variability among those with ASD. Here we show that part of this heterogeneity can be explained by level of language functioning. We recorded semi-spontaneous but controlled conversations in adults with and without Autism Spectrum Disorder and measured features related to pitch and duration to determine (1) general use of prosodic features, (2) prosodic use in relation to marking information structure, specifically, the emphasis of new information in a sentence (focus) as opposed to information already given in the conversational context (topic), and (3) the relation between prosodic use and level of language function. We found that, compared to typical adults, those with ASD with high language functioning generally used a larger pitch range than controls but did not mark information structure, whereas those with moderate language functioning generally used a smaller pitch range than controls but marked information structure appropriately to a large extent. Both impaired general prosodic use and impaired marking of information structure would be expected to seriously impact social communication and thereby lead to increased difficulty in personal domains, such as making and keeping friendships, and in professional domains, such as competing for employment opportunities.

Abstract

Investigation of the biological basis of human speech and language is being transformed by developments in molecular technologies, including high-throughput genotyping and next-generation sequencing of whole genomes. These advances are shedding new light on the genetic architecture underlying language-related disorders (speech apraxia, specific language impairment, developmental dyslexia) as well as that contributing to variation in relevant skills in the general population. We discuss how state-of-the-art methods are uncovering a range of genetic mechanisms, from rare mutations of large effect to common polymorphisms that increase risk in a subtle way, while converging on neurogenetic pathways that are shared between distinct disorders. We consider the future of the field, highlighting the unusual challenges and opportunities associated with studying genomics of language-related traits.

Abstract

Intellectual disability (ID) is a severe neurodevelopmental disorder with genetically heterogeneous causes. Large-scale sequencing has led to the identification of many gene-disrupting mutations; however, a substantial proportion of cases lack a molecular diagnosis. As such, there remains much to uncover for a complete understanding of the genetic underpinnings of ID. Genetic variants present in non-coding regions of the genome have been highlighted as potential contributors to neurodevelopmental disorders given their role in regulating gene expression. Nevertheless the functional characterization of non-coding variants remains challenging. We describe the identification and characterization of de novo non-coding variation in 3′UTR regulatory regions within an ID cohort of 50 patients. This cohort was previously screened for structural and coding pathogenic variants via CNV, whole exome and whole genome analysis. We identified 44 high-confidence single nucleotide non-coding variants within the 3′UTR regions of these 50 genomes. Four of these variants were located within predicted miRNA binding sites and were thus hypothesised to have regulatory consequences. Functional testing showed that two of the variants interfered with miRNA-mediated regulation of their target genes, AMD1 and FAIM. Both these variants were found in the same individual and their functional consequences may point to a potential role for such variants in intellectual disability.

Abstract

Understanding the genetic factors underlying neurodevelopmental and neuropsychiatric disorders is a major challenge given their prevalence and potential severity for quality of life. While large-scale genomic screens have made major advances in this area, for many disorders the genetic underpinnings are complex and poorly understood. To date the field has focused predominantly on protein coding variation, but given the importance of tightly controlled gene expression for normal brain development and disorder, variation that affects non-coding regulatory regions of the genome is likely to play an important role in these phenotypes. Herein we show the importance of 3 prime untranslated region (3'UTR) non-coding regulatory variants across neurodevelopmental and neuropsychiatric disorders. We devised a pipeline for identifying and functionally validating putatively pathogenic variants from next generation sequencing (NGS) data. We applied this pipeline to a cohort of children with severe specific language impairment (SLI) and identified a functional, SLI-associated variant affecting gene regulation in cells and post-mortem human brain. This variant and the affected gene (ARHGEF39) represent new putative risk factors for SLI. Furthermore, we identified 3′UTR regulatory variants across autism, schizophrenia and bipolar disorder NGS cohorts demonstrating their impact on neurodevelopmental and neuropsychiatric disorders. Our findings show the importance of investigating non-coding regulatory variants when determining risk factors contributing to neurodevelopmental and neuropsychiatric disorders. In the future, integration of such regulatory variation with protein coding changes will be essential for uncovering the genetic causes of complex neurological disorders and the fundamental mechanisms underlying health and disease

Abstract

Background: Human fibroblasts can be directly converted to several subtypes of neurons, but cortical projection neurons have not been generated. Methods: Here we screened for transcription factor combinations that could potentially convert human fibroblasts to functional excitatory cortical neurons. The induced cortical (iCtx) cells were analyzed for cortical neuronal identity using immunocytochemistry, single-cell quantitative polymerase chain reaction (qPCR), electrophysiology, and their ability to integrate into human neural networks in vitro and ex vivo using electrophysiology and rabies virus tracing. Results: We show that a combination of three ranscription fact ors, BRN2, MYT1L, and FEZF2, have the ability to directly convert human fibroblasts to functional excitatory cortical neurons. The conversion efficiency was increased to about 16% by treatment with small molecules and microRNAs. The iCtx cells exhibited electrophysiological properties of functional neurons, had pyramidal-like cell morphology, and expressed key cortical projection neuronal markers. Single-cell analysis of iCtx cells revealed a complex gene expression profile, a subpopulation of them displaying a molecular signature closely resembling that of human fetal primary cortical neurons. The iCtx cells received synaptic inputs from co-cultured human fetal primary cortical neurons, contained spines, and expressed the postsyna ptic excitatory scaffold protein PSD95. When transplanted ex vivo to organotypic cultures of adult human cerebral cortex, the iCtx cells exhibited morphological and electrophysiological properties of mature neurons, integrated structurally into the cortical tissue, and received synaptic inputs from adult human neurons. Conclusions: Our findings indicate that functional excitatory cortical neurons, generated here for the first time by direct conversion of human somatic cells, have the capacity for synaptic integration into adult human cortex.