Publications

Abstract

When Tzeltal children in the Mayan community of Tenejapa, in southern Mexico, begin speaking, their production vocabulary consists predominantly of verb roots, in contrast to the dominance of nouns in the initial vocabulary of first‐language learners of Indo‐European languages. This article proposes that a particular Tzeltal conversational feature—known in the Mayanist literature as "dialogic repetition"—provides a context that facilitates the early analysis and use of verbs. Although Tzeltal babies are not treated by adults as genuine interlocutors worthy of sustained interaction, dialogic repetition in the speech the children are exposed to may have an important role in revealing to them the structural properties of the language, as well as in socializing the collaborative style of verbal interaction adults favor in this community.

Abstract

The surge of research activity focussing on children's acquisition of verbs (e.g., Tomasello and Merriman 1996) addresses some fundamental questions: Just how variable across languages, and across individual children, is the process of verb learning? How specific are arguments to particular verbs in early child language? How does the grammatical category 'Verb' develop? The position of Universal Grammar, that a verb category is early, contrasts with that of Tomasello (1992), Pine and Lieven and their colleagues (1996, in press), and many others, that children develop a verb category slowly, gradually building up subcategorizations of verbs around pragmatic, syntactic, and semantic properties of the language they are exposed to. On this latter view, one would expect the language which the child is learning, the cultural milieu and the nature of the interactions in which the child is engaged, to influence the process of acquiring verb argument structures. This paper explores these issues by examining the development of argument representation in the Mayan language Tzeltal, in both its lexical and verbal cross-referencing forms, and analyzing the semantic and pragmatic factors influencing the form argument representation takes. Certain facts about Tzeltal (the ergative/ absolutive marking, the semantic specificity of transitive and positional verbs) are proposed to affect the representation of arguments. The first 500 multimorpheme combinations of 3 children (aged between 1;8 and 2;4) are examined. It is argued that there is no evidence of semantically light 'pathbreaking' verbs (Ninio 1996) leading the way into word combinations. There is early productivity of cross-referencing affixes marking A, S, and O arguments (although there are systematic omissions). The paper assesses the respective contributions of three kinds of factors to these results - structural (regular morphology), semantic (verb specificity) and pragmatic (the nature of Tzeltal conversational interaction).

Abstract

In a famous paper Harvey Sacks (1974) argued that the sequential properties of greeting conventions, as well as those governing the flow of information, mean that 'everyone has to lie'. In this paper I show this dictum to be equally true in the Tzeltal Mayan community of Tenejapa, in southern Mexico, but for somewhat different reasons. The phenomenon of interest is the practice of routine fearsome threats to small children. Based on a longitudinal corpus of videotaped and tape-recorded naturally-occurring interaction between caregivers and children in five Tzeltal families, the study examines sequences of Tzeltal caregivers' speech aimed at controlling the children's behaviour and analyzes the children's developing pragmatic skills in handling such controlling utterances, from prelinguistic infants to age five and over. Infants in this society are considered to be vulnerable, easily scared or shocked into losing their 'souls', and therefore at all costs to be protected and hidden from outsiders and other dangers. Nonetheless, the chief form of control (aside from physically removing a child from danger) is to threaten, saying things like "Don't do that, or I'll take you to the clinic for an injection," These overt scare-threats - rarely actually realized - lead Tzeltal children by the age of 2;6 to 3;0 to the understanding that speech does not necessarily convey true propositions, and to a sensitivity to the underlying motivations for utterances distinct from their literal meaning. By age 4;0 children perform the same role to their younger siblings;they also begin to use more subtle non-true (e.g. ironic) utterances. The caretaker practice described here is related to adult norms of social lying, to the sociocultural context of constraints on information flow, social control through gossip, and the different notion of 'truth' that arises in the context of non-verifiability characteristic of a small-scale nonliterate society.

Abstract

This paper surveys the concept of culture as used in recent work in cognitive science, assessing the very different (and sometimes minimal) role 'culture' plays in different branches and schools of linguistics: generative approaches, descriptive/comparative linguistics, typology, cognitive linguistics, semantics, pragmatics, psycholinguistics, linguistic and cognitive anthropology. The paper then describes research on one specific topic, spatial language and conceptualization, describes a methodology for studying it cross-linguistically and cross-culturally. Finally, it considers the implications of results in this area for how we can fruitfully conceptualize 'culture', arguing for an approach which shifts back and forth between individual mind and collective representations, between universals and particulars, and ties 'culture' to our biological roots.

Abstract

This is a Spanish translation of Brown 1997.

Abstract

This article is a reprint of chapter 1, the introduction to Brown and Levinson, 1987, Politeness: Some universals in language usage (Cambridge University Press).

Abstract

Speech input causes listeners to activate multiple
candidate words which then compete with one
another. These include onset competitors, that share a
beginning (bumper, butter), but also, counterintuitively,
rhyme competitors, sharing an ending
(bumper, jumper). In L1, competition is typically
stronger for onset than for rhyme. In L2, onset
competition has been attested but rhyme competition
has heretofore remained largely unexamined. We
assessed L1 (Dutch) and L2 (English) word
recognition by the same late-bilingual individuals. In
each language, eye gaze was recorded as listeners
heard sentences and viewed sets of drawings: three
unrelated, one depicting an onset or rhyme competitor
of a word in the input. Activation patterns revealed
substantial onset competition but no significant
rhyme competition in either L1 or L2. Rhyme
competition may thus be a “luxury” feature of
maximally efficient listening, to be abandoned when
resources are scarcer, as in listening by late
bilinguals, in either language.

Abstract

For multimodal annotations an exhaustive encoding system for gestures was developed to facilitate research. The structural requirements of multimodal annotations were analyzed to develop an Abstract Corpus Model which is the basis for a powerful annotation and exploitation tool for multimedia recordings and the definition of the XML-based EUDICO Annotation Format. Finally, a metadata-based data management environment has been setup to facilitate resource discovery and especially corpus management. Bt means of an appropriate digitization policy and their online availability researchers have been able to build up a large corpus covering gesture and sign language data.

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

The human brain can process facial expressions of emotions rapidly and without awareness. Several studies in patients with damage to their primary visual cortices have shown that they may be able to guess the emotional expression on a face despite their cortical blindness. This non-conscious processing, called affective blindsight, may arise through an intact subcortical visual route that leads from the superior colliculus to the pulvinar, and thence to the amygdala. This pathway is thought to process the crude visual information conveyed by the low spatial frequencies of the stimuli.

In order to investigate whether this is the case, we studied a patient (TN) with bilateral cortical blindness and affective blindsight. An fMRI paradigm was performed in which fearful and neutral expressions were presented using faces that were either unfiltered, or filtered to remove high or low spatial frequencies. Unfiltered fearful faces produced right amygdala activation although the patient was unaware of the presence of the stimuli. More importantly, the low spatial frequency components of fearful faces continued to produce right amygdala activity while the high spatial frequency components did not. Our findings thus confirm that the visual information present in the low spatial frequencies is sufficient to produce affective blindsight, further suggesting that its existence could rely on the subcortical colliculo-pulvino-amygdalar pathway.

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

Most people have left‐hemisphere dominance for various aspects of language processing, but only roughly 1% of the adult population has atypically reversed, rightward hemispheric language dominance (RHLD). The genetic‐developmental program that underlies leftward language laterality is unknown, as are the causes of atypical variation. We performed an exploratory whole‐genome‐sequencing study, with the hypothesis that strongly penetrant, rare genetic mutations might sometimes be involved in RHLD. This was by analogy with situs inversus of the visceral organs (left‐right mirror reversal of the heart, lungs and so on), which is sometimes due to monogenic mutations. The genomes of 33 subjects with RHLD were sequenced and analyzed with reference to large population‐genetic data sets, as well as 34 subjects (14 left‐handed) with typical language laterality. The sample was powered to detect rare, highly penetrant, monogenic effects if they would be present in at least 10 of the 33 RHLD cases and no controls, but no individual genes had mutations in more than five RHLD cases while being un‐mutated in controls. A hypothesis derived from invertebrate mechanisms of left‐right axis formation led to the detection of an increased mutation load, in RHLD subjects, within genes involved with the actin cytoskeleton. The latter finding offers a first, tentative insight into molecular genetic influences on hemispheric language dominance.

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

Recent years have seen rapid technological development of devices that can record communicative behavior as participants go about daily life. This paper is intended as an end-to-end methodological guidebook for potential users of these technologies, including researchers who want to study children’s or adults’ communicative behavior in everyday contexts. We explain how long-format speech environment (LFSE) recordings provide a unique view on language use and how they can be used to complement other measures at the individual and group level. We aim to help potential users of these technologies make informed decisions regarding research design, hardware, software, and archiving. We also provide information regarding ethics and implementation, issues that are difficult to navigate for those new to this technology, and on which little or no resources are available. This guidebook offers a concise summary of information for new users and points to sources of more detailed information for more advanced users. Links to discussion groups and community-augmented databases are also provided to help readers stay up-to-date on the latest developments.

Abstract

Odor naming is enhanced in communities where communication about odors is a central part of daily life (e.g., wine experts, flavorists, and some hunter‐gatherer groups). In this study, we investigated how expert knowledge and daily experience affect the ability to name odors in a group of experts that has not previously been investigated in this context—Iranian herbalists; also called attars—as well as cooks and laypeople. We assessed naming accuracy and consistency for 16 herb and spice odors, collected judgments of odor perception, and evaluated participants' odor meta‐awareness. Participants' responses were overall more consistent and accurate for more frequent and familiar odors. Moreover, attars were more accurate than both cooks and laypeople at naming odors, although cooks did not perform significantly better than laypeople. Attars' perceptual ratings of odors and their overall odor meta‐awareness suggest they are also more attuned to odors than the other two groups. To conclude, Iranian attars—but not cooks—are better odor namers than laypeople. They also have greater meta‐awareness and differential perceptual responses to odors. These findings further highlight the critical role that expertise and type of experience have on olfactory functions.

Abstract

FOXP proteins form a subfamily of evolutionarily conserved transcription factors involved in the development and functioning of several tissues, including the central nervous system. In humans, mutations in FOXP1 and FOXP2 have been implicated in cognitive deficits including intellectual disability and speech disorders. Drosophila exhibits a single ortholog, called FoxP, but due to a lack of characterized mutants, our understanding of the gene remains poor. Here we show that the dimerization property required for mammalian FOXP function is conserved in Drosophila. In flies, FoxP is enriched in the adult brain, showing strong expression in ~1000 neurons of cholinergic, glutamatergic and GABAergic nature. We generate Drosophila loss-of-function mutants and UAS-FoxP transgenic lines for ectopic expression, and use them to characterize FoxP function in the nervous system. At the cellular level, we demonstrate that Drosophila FoxP is required in larvae for synaptic morphogenesis at axonal terminals of the neuromuscular junction and for dendrite development of dorsal multidendritic sensory neurons. In the developing brain, we find that FoxP plays important roles in α-lobe mushroom body formation. Finally, at a behavioral level, we show that Drosophila FoxP is important for locomotion, habituation learning and social space behavior of adult flies. Our work shows that Drosophila FoxP is important for regulating several neurodevelopmental processes and behaviors that are related to human disease or vertebrate disease model phenotypes. This suggests a high degree of functional conservation with vertebrate FOXP orthologues and established flies as a model system for understanding FOXP related pathologies.

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

Oligodendrocyte gene expression is downregulated in stress-related neuropsychiatric disorders,
including depression. In mice, chronic social stress (CSS) leads to depression-relevant changes
in brain and emotional behavior, and the present study shows the involvement of oligodendrocytes in this model. In C57BL/6 (BL/6) mice, RNA-sequencing (RNA-Seq) was conducted with
prefrontal cortex, amygdala and hippocampus from CSS and controls; a gene enrichment database for neurons, astrocytes and oligodendrocytes was used to identify cell origin of deregulated genes, and cell deconvolution was applied. To assess the potential causal contribution of
reduced oligodendrocyte gene expression to CSS effects, mice heterozygous for the oligodendrocyte gene cyclic nucleotide phosphodiesterase (Cnp1) on a BL/6 background were studied;
a 2 genotype (wildtype, Cnp1+/−
) × 2 environment (control, CSS) design was used to investigate
effects on emotional behavior and amygdala microglia. In BL/6 mice, in prefrontal cortex and
amygdala tissue comprising gray and white matter, CSS downregulated expression of multiple
oligodendroycte genes encoding myelin and myelin-axon-integrity proteins, and cell deconvolution identified a lower proportion of oligodendrocytes in amygdala. Quantification of oligodendrocyte proteins in amygdala gray matter did not yield evidence for reduced translation,
suggesting that CSS impacts primarily on white matter oligodendrocytes or the myelin transcriptome. In Cnp1 mice, social interaction was reduced by CSS in Cnp1+/− mice specifically;
using ionized calcium-binding adaptor molecule 1 (IBA1) expression, microglia activity was
increased additively by Cnp1+/− and CSS in amygdala gray and white matter. This study provides back-translational evidence that oligodendrocyte changes are relevant to the pathophysiology and potentially the treatment of stress-related neuropsychiatric disorders.

Abstract

We report on an analysis of spontaneous gesture production in 2‐year‐old children who come from three countries (Italy, United Kingdom, Australia) and who speak two languages (Italian, English), in an attempt to tease apart the influence of language and culture when comparing children from different cultural and linguistic environments. Eighty‐seven monolingual children aged 24–30 months completed an experimental task measuring their comprehension and production of nouns and predicates. The Italian children scored significantly higher than the other groups on all lexical measures. With regard to gestures, British children produced significantly fewer pointing and speech combinations compared to Italian and Australian children, who did not differ from each other. In contrast, Italian children produced significantly more representational gestures than the other two groups. We conclude that spoken language development is primarily influenced by the input language over gesture production, whereas the combination of cultural and language environments affects gesture production.

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

Cognitive development is shaped by interactions between cognitive architecture and environmental experiences
of the growing brain. We examined the extent to which this interaction during development could be observed in
language processing. We focused on age of acquisition (AoA) effects in reading, where early-learned words tend
to be processed more quickly and accurately relative to later-learned words. We implemented a computational
model including representations of print, sound and meaning of words, with training based on children’s gradual
exposure to language. The model produced AoA effects in reading and lexical decision, replicating the larger
effects of AoA when semantic representations are involved. Further, the model predicted that AoA would relate
to differing use of the reading system, with words acquired before versus after literacy onset with distinctive
accessing of meaning and sound representations. An analysis of behaviour from the English Lexicon project was
consistent with the predictions: Words acquired before literacy are more likely to access meaning via sound,
showing a suppressed AoA effect, whereas words acquired after literacy rely more on direct print to meaning
mappings, showing an exaggerated AoA effect. The reading system reveals vestigial traces of acquisition reflected
in differing use of word representations during reading.

Abstract

Diversity of vocabulary knowledge and quantity of language exposure prior to literacy are key predictors of reading development. However, diversity and quantity of exposure are difficult to distinguish in behavioural studies, and so the causal relations with literacy are not well known. We tested these relations by training a connectionist triangle model of reading that learned to map between semantic; phonological; and, later, orthographic forms of words. The model first learned to map between phonology and semantics, where we manipulated the quantity and diversity of this preliterate language experience. Then the model learned to read. Both diversity and quantity of exposure had unique effects on reading performance, with larger effects for written word comprehension than for reading fluency. The results further showed that quantity of preliteracy language exposure was beneficial only when this was to a varied vocabulary and could be an impediment when exposed to a limited vocabulary.

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

Two groups of listeners with Dutch and British English language backgrounds judged Dutch and British English utterances, respectively, which varied in the intonation contour on the scales EMPHATIC vs. NOT EMPHATIC and SURPRISED vs. NOT SURPRISED, two meanings derived from the Effort Code. The stimuli, which differed in sentence mode but were otherwise lexically equivalent, were varied in peak height, peak alignment, end pitch, and overall register. In both languages, there are positive correlations between peak height and degree of emphasis, between peak height and degree of surprise, between peak alignment and degree of surprise, and between pitch register and degree of surprise. However, in all these cases, Dutch stimuli lead to larger perceived meaning differences than the British English stimuli. This difference in the extent to which increased pitch height triggers increases in perceived emphasis and surprise is argued to be due to the difference in the standard pitch ranges between Dutch and British English. In addition, we found a positive correlation between pitch register and the degree of emphasis in Dutch, but a negative correlation in British English. This is an unexpected difference, which illustrates a case of ambiguity in the meaning of pitch.

Abstract

This study examines acoustic and aerodynamic characteristics of consonants in standard Korean and in Cheju, an endangered Korean language. The focus is on the well-known three-way distinction among voiceless stops (i.e., lenis, fortis, aspirated) and the two-way distinction between the voiceless fricatives /s/ and /s*/. While such a typologically unusual contrast among voiceless stops has long drawn the attention of phoneticians and phonologists, there is no single work in the literature that discusses a body of data representing a relatively large number of speakers. This study reports a variety of acoustic and aerodynamic measures obtained from 12 Korean speakers (four speakers of Seoul Korean and eight speakers of Cheju). Results show that, in addition to findings similar to those reported by others, there are three crucial points worth noting. Firstly, lenis, fortis, and aspirated stops are systematically differentiated from each other by the voice quality of the following vowel. Secondly, these stops are also differentiated by aerodynamic mechanisms. The aspirated and fortis stops are similar in supralaryngeal articulation, but employ a different relation between intraoral pressure and flow. Thirdly, our study suggests that the fricative /s/ is better categorized as “lenis” rather than “aspirated”. The paper concludes with a discussion of the implications of Korean data for theories of the voicing contrast and their phonological representations.

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

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

Interactive effects between allelic variants of the serotonin transporter (5-HTT) promoter-linked polymorphic region (5-HTTLPR) and stressors on depression symptoms have been documented, as well as questioned, by meta-analyses. Translational models of constitutive 5-htt reduction and experimentally controlled stressors often led to inconsistent behavioral and molecular findings and often did not include females. The present study sought to investigate the effect of 5-htt genotype, maternal separation, and sex on the expression of stress-related candidate genes in the rat hippocampus and frontal cortex. The mRNA expression levels of Avp, Pomc, Crh, Crhbp, Crhr1, Bdnf, Ntrk2, Maoa, Maob, and Comt were assessed in the hippocampus and frontal cortex of 5-htt ± and 5-htt +/+ male and female adult rats exposed, or not, to daily maternal separation for 180 min during the first 2 postnatal weeks. Gene- and brain region-dependent, but sex-independent, interactions between 5-htt genotype and maternal separation were found. Gene expression levels were higher in 5-htt +/+ rats not exposed to maternal separation compared with the other experimental groups. Maternal separation and 5-htt +/− genotype did not yield additive effects on gene expression. Correlative relationships, mainly positive, were observed within, but not across, brain regions in all groups except in non-maternally separated 5-htt +/+ rats. Gene expression patterns in the hippocampus and frontal cortex of rats exposed to maternal separation resembled the ones observed in rats with reduced 5-htt expression regardless of sex. These results suggest that floor effects of 5-htt reduction and maternal separation might explain inconsistent findings in humans and rodents

Abstract

Four cross-modal priming experiments and two forced-choice identification experiments investigated the use of suprasegmental cues to stress in the recognition of spoken English words, by native (English-speaking) and non- native (Dutch) listeners. Previous results had indicated that suprasegmental information was exploited in lexical access by Dutch but not by English listeners. For both listener groups, recognition of visually presented target words was faster, in comparison to a control condition, after stress-matching spoken primes, either monosyllabic (mus- from MUsic /muSEum) or bisyl labic (admi- from ADmiral/admiRAtion). For native listeners, the effect of stress-mismatching bisyllabic primes was not different from that of control primes, but mismatching monosyllabic primes produced partial facilitation. For non-native listeners, both bisyllabic and monosyllabic stress-mismatching primes produced partial facilitation. Native English listeners thus can exploit suprasegmental information in spoken-word recognition, but information from two syllables is used more effectively than information from one syllable. Dutch listeners are less proficient at using suprasegmental information in English than in their native language, but, as in their native language, use mono- and bisyllabic information to an equal extent. In forced-choice identification, Dutch listeners outperformed native listeners at correctly assigning a monosyllabic fragment (e.g., mus-) to one of two words differing in stress.

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

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

Research suggests that during conversation, interlocutors coordinate their utterances by predicting the speaker’s forthcoming utterance and its end. In two experiments, we used a button-pressing task, in which participants pressed a button when they thought a speaker reached the end of their utterance, to investigate what role the wider discourse plays in turn-end prediction. Participants heard two-utterance sequences, in which the content of the second utterance was or was not constrained by the content of the first. In both experiments, participants responded earlier, but not more precisely, when the first utterance was constraining rather than unconstraining. Response times and precision were unaffected by whether they listened to dialogues or monologues (Experiment 1) and by whether they read the first utterance out loud or silently (Experiment 2), providing no indication that activation of production mechanisms facilitates prediction. We suggest that content predictions aid comprehension but not turn-end prediction.

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

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

Speaker diarization (answering 'who spoke when') is a widely researched subject within speech technology. Numerous experiments have been run on datasets built from broadcast news, meeting data, and call centers—the task sometimes appears close to being solved. Much less work has begun to tackle the hardest diarization task of all: spontaneous conversations in real-world settings. Such diarization would be particularly useful for studies of language acquisition, where researchers investigate the speech children produce and hear in their daily lives. In this paper, we study audio gathered with a recorder worn by small children as they went about their normal days. As a result, each child was exposed to different acoustic environments with a multitude of background noises and a varying number of adults and peers. The inconsistency of speech and noise within and across samples poses a challenging task for speaker diarization systems, which we tackled via retraining and data augmentation techniques. We further studied sources of structured variation across raw audio files, including the impact of speaker type distribution, proportion of speech from children, and child age on diarization performance. We discuss the extent to which these findings might generalize to other samples of speech in the wild.

Abstract

When we imagine objects or events, we often engage in multisensory mental imagery. Yet, investigations of mental imagery have typically focused on only one sensory modality — vision. One reason for this is that the most common tool for the measurement of imagery, the questionnaire, has been restricted to unimodal ratings of the object. We present a new mental imagery questionnaire that measures multisensory imagery. Specifically, the newly developed Vividness of Wine Imagery Questionnaire (VWIQ) measures mental imagery of wine in the visual, olfactory, and gustatory modalities. Wine is an ideal domain to explore multisensory imagery because wine drinking is a multisensory experience, it involves the neglected chemical senses (smell and taste), and provides the opportunity to explore the effect of experience and expertise on imagery (from wine novices to experts). The VWIQ questionnaire showed high internal consistency and reliability, and correlated with other validated measures of imagery. Overall, the VWIQ may serve as a useful tool to explore mental imagery for researchers, as well as individuals in the wine industry during sommelier training and evaluation of wine professionals.

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

We report associations between vowel sounds, graphemes, and colours collected online from over 1000 Dutch speakers. We provide open materials including a Python implementation of the structure measure, and code for a single page web application to run simple cross-modal tasks. We also provide a full dataset of colour-vowel associations from 1164 participants, including over 200 synaesthetes identified using consistency measures. Our analysis reveals salient patterns in cross-modal associations, and introduces a novel measure of isomorphism in cross-modal mappings. We find that while acoustic features of vowels significantly predict certain mappings (replicating prior work), both vowel phoneme category and grapheme category are even better predictors of colour choice. Phoneme category is the best predictor of colour choice overall, pointing to the importance of phonological representations in addition to acoustic cues. Generally, high/front vowels are lighter, more green, and more yellow than low/back vowels. Synaesthetes respond more strongly on some dimensions, choosing lighter and more yellow colours for high and mid front vowels than non-synaesthetes. We also present a novel measure of cross-modal mappings adapted from ecology, which uses a simulated distribution of mappings to measure the extent to which participants' actual mappings are structured isomorphically across modalities. Synaesthetes have mappings that tend to be more structured than non-synaesthetes, and more consistent colour choices across trials correlate with higher structure scores. Nevertheless, the large majority (~70%) of participants produce structured mappings, indicating that the capacity to make isomorphically structured mappings across distinct modalities is shared to a large extent, even if the exact nature of mappings varies across individuals. Overall, this novel structure measure suggests a distribution of structured cross-modal association in the population, with synaesthetes on one extreme and participants with unstructured associations on the other.

Abstract

Rhythmic categories such as morae in Japanese or stress units in English play a role in the perception of spoken
language. We examined this role in Japanese, since recent evidence suggests that morae may intervene as
structural units in word recognition. First, we found that traditional puns more often substituted part of a mora
than a whole mora. Second, when listeners reconstructed distorted words, e.g. panorama from panozema, responses
were faster and more accurate when only a phoneme was distorted (panozama, panorema) than when a
whole CV mora was distorted (panozema). Third, lexical decisions on the same nonwords were better predicted
by duration and number of phonemes from nonword uniqueness point to word end than by number of morae. Our
results indicate no role for morae in early spoken-word processing; we propose that rhythmic categories constrain
not initial lexical activation but subsequent processes of speech segmentation and selection among word candidates.

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

The Possible Word Constraint is a proposed mechanism whereby listeners avoid recognising words spuriously embedded in other words. It applies to words leaving a vowelless residue between their edge and the nearest known word or syllable boundary. The present study tests the usefulness of this constraint via lexical statistics of both English and Dutch. The analyses demonstrate that the constraint removes a clear majority of embedded words in speech, and thus can contribute significantly to the efficiency of human speech recognition

Abstract

Recognizing spoken language involves automatic activation of multiple candidate words. The process of selection between candidates is made more efficient by inhibition of embedded words (like egg in beg) that leave a portion of the input stranded (here, b). Results from European languages suggest that this inhibition occurs when consonants are stranded but not when syllables are stranded. The reason why leftover syllables do not lead to inhibition could be that in principle they might themselves be words; in European languages, a syllable can be a word. In Sesotho (a Bantu language), however, a single syllable cannot be a word. We report that in Sesotho, word recognition is inhibited by stranded consonants, but stranded monosyllables produce no more difficulty than stranded bisyllables (which could be Sesotho words). This finding suggests that the viability constraint which inhibits spurious embedded word candidates is not sensitive to language-specific word structure, but is universal.

Abstract

Part of the remarkable efficiency of listening is
accommodation to unfamiliar talkers’ specific
pronunciations by retuning of phonemic intercategory
boundaries. Such retuning occurs in second
(L2) as well as first language (L1); however, recent
research with emigrés revealed successful adaptation
in the environmental L2 but, unprecedentedly, not in
L1 despite continuing L1 use. A possible explanation
involving relative exposure to novel talkers is here
tested in heritage language users with Mandarin as
family L1 and English as environmental language. In
English, exposure to an ambiguous sound in
disambiguating word contexts prompted the expected
adjustment of phonemic boundaries in subsequent
categorisation. However, no adjustment occurred in
Mandarin, again despite regular use. Participants
reported highly asymmetric interlocutor counts in the
two languages. We conclude that successful retuning
ability requires regular exposure to novel talkers in
the language in question, a criterion not met for the
emigrés’ or for these heritage users’ L1.

Abstract

Assimilation of place of articulation across a nasal and a following stop consonant is obligatory in Japanese, but not in Dutch. In four experiments the processing of assimilated forms by speakers of Japanese and Dutch was compared, using a task in which listeners blended pseudo-word pairs such as ranga-serupa. An assimilated blend of this pair would be rampa, an unassimilated blend rangpa. Japanese listeners produced significantly more assimilated than unassimilated forms, both with pseudo-Japanese and pseudo-Dutch materials, while Dutch listeners produced significantly more unassimilated than assimilated forms in each materials set. This suggests that Japanese listeners, whose native-language phonology involves obligatory assimilation constraints, represent the assimilated nasals in nasal-stop sequences as unmarked for place of articulation, while Dutch listeners, who are accustomed to hearing unassimilated forms, represent the same nasal segments as marked for place of articulation.

Abstract

In two experiments, Mandarin listeners resolved potential syntactic ambiguities in spoken utterances in (a) their native language (L1) and (b) English which they had learned as a second language (L2). A new disambiguation task was used, requiring speeded responses to select the correct meaning for structurally ambiguous sentences. Importantly, the ambiguities used in the study are identical in Mandarin and in English, and production data show that prosodic disambiguation of this type of ambiguity is also realised very similarly in the two languages. The perceptual results here showed however that listeners’ response patterns differed for L1 and L2, although there was a significant increase in similarity between the two response patterns with increasing exposure to the L2. Thus identical ambiguity and comparable disambiguation patterns in L1 and L2 do not lead to immediate application of the appropriate L1 listening strategy to L2; instead, it appears that such a strategy may have to be learned anew for the L2.

Abstract

Using a phoneme detection task, the present series of
experiments examines whether listeners can entrain to
different combinations of prosodic cues to predict where focus
will fall in an utterance. The stimuli were recorded by four
female native speakers of Australian English who happened to
have used different prosodic cues to produce sentences with
prosodic focus: a combination of duration cues, mean and
maximum F0, F0 range, and longer pre-target interval before
the focused word onset, only mean F0 cues, only pre-target
interval, and only duration cues. Results revealed that listeners
can entrain in almost every condition except for where
duration was the only reliable cue. Our findings suggest that
listeners are flexible in the cues they use for focus processing.

Abstract

Becoming a native listener is the necessary precursor to becoming a native speaker. Babies in the first year of life undertake a remarkable amount of work; by the time they begin to speak, they have perceptually mastered the phonological repertoire and phoneme co-occurrence probabilities of the native language, and they can locate familiar word-forms in novel continuous-speech contexts. The skills acquired at this early stage form a necessary part of adult listening. However, the same native listening skills also underlie problems in listening to a late-acquired non-native language, accounting for why in such a case listening (an innate ability) is sometimes paradoxically more difficult than, for instance, reading (a learned ability).

Abstract

Listeners adapt rapidly to previously unheard talkers by
adjusting phoneme categories using lexical knowledge, in a
process termed lexically-guided perceptual learning. Although
this is firmly established for listening in the native language
(L1), perceptual flexibility in second languages (L2) is as yet
less well understood. We report two experiments examining L1
and L2 perceptual learning, the first in Mandarin-English late
bilinguals, the second in Australian learners of Mandarin. Both
studies showed stronger learning in L1; in L2, however,
learning appeared for the English-L1 group but not for the
Mandarin-L1 group. Phonological mapping differences from
the L1 to the L2 are suggested as the reason for this result.

Abstract

Languages contain tens of thousands of words, but these are constructed from a tiny handful of phonetic elements. Consequently, words resemble one another, or can be embedded within one another, a coup stick snot with standing. me process of spoken-word recognition by human listeners involves activation of multiple word candidates consistent with the input, and direct competition between activated candidate words. Further, human listeners are sensitive, at an early, prelexical, stage of speeeh processing, to constraints on what could potentially be a word of the language.

Abstract

Listeners' recognition of spoken language involves complex decoding processes: The continuous speech stream must be segmented into its component words, and words must be recognized despite great variability in their pronunciation (due to talker differences, or to influence of phonetic context, or to speech register) and despite competition from many spuriously present forms supported by the speech signal. L1 listeners deal more readily with all levels of this complexity than L2 listeners. Fortunately, the decoding processes necessary for competent L2 listening can be taught in the classroom. Evidence-based methodologies targeted at the development of efficient speech decoding include teaching of minimal pairs, of phonotactic constraints, and of reduction processes, as well as the use of dictation and L2 video captions.

Abstract

The phoneme detection task is widely used in spoken word recognition research. Alphabetically literate participants, however, are more used to explicit representations of letters than of phonemes. The present study explored whether phoneme detection is sensitive to how target phonemes are, or may be, orthographically realised. Listeners detected the target sounds [b,m,t,f,s,k] in word-initial position in sequences of isolated English words. Response times were faster to the targets [b,m,t], which have consistent word-initial spelling, than to the targets [f,s,k], which are inconsistently spelled, but only when listeners’ attention was drawn to spelling by the presence in the experiment of many irregularly spelled fillers. Within the inconsistent targets [f,s,k], there was no significant difference between responses to targets in words with majority and minority spellings. We conclude that performance in the phoneme detection task is not necessarily sensitive to orthographic effects, but that salient orthographic manipulation can induce such sensitivity.

Abstract

The role of accent in reference resolution was investigated by monitoring eye fixations to lexical competitors (e.g., candy and candle ) as participants followed prerecorded instructions to move objects above or below fixed geometric shapes using a computer mouse. In Experiment 1, the first utterance instructed participants to move one object above or below a shape (e.g., “Put the candle/candy below the triangle”) and the second utterance contained an accented or deaccented definite noun phrase which referred to the same object or introduced a new entity (e.g., “Now put the CANDLE above the square” vs. “Now put the candle ABOVE THE SQUARE”). Fixations to the competitor (e.g., candy ) demonstrated a bias to interpret deaccented nouns as anaphoric and accented nouns as nonanaphoric. Experiment 2 used only accented nouns in the second instruction, varying whether the referent of this second instruction was the Theme of the first instruction (e.g., “Put the candle below the triangle”) or the Goal of the first instruction (e.g., “Put the necklace below the candle”). Participants preferred to interpret accented noun phrases as referring to a previously mentioned nonfocused entity (the Goal) rather than as introducing a new unmentioned entity.

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

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

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 argues that inter-individual and inter-group variation in language acquisition, perception, processing and production, rooted in our biology, may play a largely neglected role in sound change. We begin by discussing the patterning of these differences, highlighting those related to vocal tract anatomy with a foundation in genetics and development. We use our ArtiVarK database, a large multi-ethnic sample comprising 3D intraoral optical scans, as well as structural, static and real-time MRI scans of vocal tract anatomy and speech articulation, to quantify the articulatory strategies used to produce the North American English /r/ and to statistically show that anatomical factors seem to influence these articulatory strategies. Building on work showing that these alternative articulatory strategies may have indirect coarticulatory effects, we propose two models for how biases due to variation in vocal tract anatomy may affect sound change. The first involves direct overt acoustic effects of such biases that are then reinterpreted by the hearers, while the second is based on indirect coarticulatory phenomena generated by acoustically covert biases that produce overt “at-a-distance” acoustic effects. This view implies that speaker communities might be “poised” for change because they always contain pools of “standing variation” of such biased speakers, and when factors such as the frequency of the biased speakers in the community, their positions in the communicative network or the topology of the network itself change, sound change may rapidly follow as a self-reinforcing network-level phenomenon, akin to a phase transition. Thus, inter-speaker variation in structured and dynamic communicative networks may couple the initiation and actuation of sound change.

Abstract

Linguistic diversity is affected by multiple factors, but it is usually assumed that variation in the anatomy of our speech organs
plays no explanatory role. Here we use realistic computer models of the human speech organs to test whether inter-individual
and inter-group variation in the shape of the hard palate (the bony roof of the mouth) affects acoustics of speech sounds. Based
on 107 midsagittal MRI scans of the hard palate of human participants, we modelled with high accuracy the articulation of a set
of five cross-linguistically representative vowels by agents learning to produce speech sounds. We found that different hard
palate shapes result in subtle differences in the acoustics and articulatory strategies of the produced vowels, and that these
individual-level speech idiosyncrasies are amplified by the repeated transmission of language across generations. Therefore,
we suggest that, besides culture and environment, quantitative biological variation can be amplified, also influencing language.

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.