Publications

Abstract

Previous studies show that young, typically developing (TD) children (age 5) make errors in the choice between a definite and an indefinite article. Suggested explanations for overgeneration of the definite article include failure to distinguish speaker from hearer assumptions, and for overgeneration of the indefinite article failure to draw scalar implicatures, and weak working memory. However, no direct empirical evidence for these accounts is available. In this study, 27 Dutch-speaking children with high-functioning autism, 27 children with SLI, and 27 TD children aged 5–14 were administered a pragmatic article choice test, a nonverbal theory of mind test, and three types of memory tests (phonological memory, verbal, and nonverbal working memory). The results show that the children with high-functioning autism and SLI (a) make similar errors, that is, they overgenerate the indefinite article; (b) are TD-like at theory of mind, but (c) perform significantly more poorly than the TD children on phonological memory and verbal working memory. We propose that weak memory skills prevent the integration of the definiteness scale with the preceding discourse, resulting in the failure to consistently draw the relevant scalar implicature. This in turn yields the occasional erroneous choice of the indefinite article a in definite contexts.

Abstract

Numerous studies have shown that younger adults engage in lexically guided perceptual learning in speech perception. Here, we investigated whether older listeners are also able to retune their phonetic category boundaries. More specifically, in this research we tried to answer two questions. First, do older adults show perceptual-learning effects of similar size to those of younger adults? Second, do differences in lexical behavior predict the strength of the perceptual-learning effect? An age group comparison revealed that older listeners do engage in lexically guided perceptual learning, but there were two age-related differences: Younger listeners had a stronger learning effect right after exposure than did older listeners, but the effect was more stable for older than for younger listeners. Moreover, a clear link was shown to exist between individuals’ lexical-decision performance during exposure and the magnitude of their perceptual-learning effects. A subsequent analysis on the results of the older participants revealed that, even within the older participant group, with increasing age the perceptual retuning effect became smaller but also more stable, mirroring the age group comparison results. These results could not be explained by differences in hearing loss. The age effect may be accounted for by decreased flexibility in the adjustment of phoneme categories or by age-related changes in the dynamics of spoken-word recognition, with older adults being more affected by competition from similar-sounding lexical competitors, resulting in less lexical guidance for perceptual retuning. In conclusion, our results clearly show that the speech perception system remains flexible over the life span.

Abstract

The coinciding form and meaning similarity of cognates, e.g. ‘flamme’ (French), ‘Flamme’ (German), ‘vlam’ (Dutch), meaning ‘flame’ in English, facilitates learning of additional languages. The cross-language frequency and similarity distributions of cognates vary according to evolutionary change and language contact. We compare frequency and orthographic (O), phonetic (P), and semantic similarity of cognates, automatically identified in semi-complete lexicons of six widely spoken languages. Comparisons of P and O similarity reveal inconsistent mappings in language pairs with deep orthographies. The frequency distributions show that cognate frequency is reduced in less closely related language pairs as compared to more closely related languages (e.g., French-English vs. German-English). These frequency and similarity patterns may support a better understanding of cognate processing in natural and experimental settings. The automatically identified cognates are available in the supplementary materials, including the frequency and similarity measurements.

Abstract

Large-scale genome-wide association studies (GWAS) have implicated many low-penetrance loci in schizophrenia. However, its pathological mechanisms are poorly understood, which in turn hampers the development of novel pharmacological treatments. Pathway and gene set analyses carry the potential to generate hypotheses about disease mechanisms and have provided biological context to genome-wide data of schizophrenia. We aimed to examine which biological processes are likely candidates to underlie schizophrenia by integrating novel and powerful pathway analysis tools using data from the largest Psychiatric Genomics Consortium schizophrenia GWAS (N=79,845) and the most recent 2018 schizophrenia GWAS (N=105,318). By applying a primary unbiased analysis (Multi-marker Analysis of GenoMic Annotation; MAGMA) to weigh the role of biological processes from the Molecular Signatures Database (MSigDB), we identified enrichment of common variants in synaptic plasticity and neuron differentiation gene sets. We supported these findings using MAGMA, Meta-Analysis Gene-set Enrichment of variaNT Associations (MAGENTA) and Interval Enrichment Analysis (INRICH) on detailed synaptic signaling pathways from the Kyoto Encyclopedia of Genes and Genomes (KEGG) and found enrichment in mainly the dopaminergic and cholinergic synapses. Moreover, shared genes involved in these neurotransmitter systems had a large contribution to the observed enrichment, protein products of top genes in these pathways showed more direct and indirect interactions than expected by chance, and expression profiles of these genes were largely similar among brain tissues. In conclusion, we provide strong and consistent genetics and protein-interaction informed evidence for the role of postsynaptic signaling processes in schizophrenia, opening avenues for future translational and psychopharmacological studies.

Abstract

The assessment of corticospinal excitability by means of transcranial magnetic stimulation-induced motor evoked potentials is an established diagnostic tool in neurophysiology and a widely used procedure in fundamental brain research. However, concern about low reliability of these measures has grown recently. One possible cause of high variability of MEPs under identical acquisition conditions could be the influence of oscillatory neuronal activity on corticospinal excitability. Based on research showing that transcranial alternating current stimulation can entrain neuronal oscillations we here test whether alpha or beta frequency tACS can influence corticospinal excitability in a phase-dependent manner. We applied tACS at individually calibrated alpha- and beta-band oscillation frequencies, or we applied sham tACS. Simultaneous single TMS pulses time locked to eight equidistant phases of the ongoing tACS signal evoked MEPs. To evaluate offline effects of stimulation frequency, MEP amplitudes were measured before and after tACS. To evaluate whether tACS influences MEP amplitude, we fitted one-cycle sinusoids to the average MEPs elicited at the different phase conditions of each tACS frequency. We found no frequency-specific offline effects of tACS. However, beta-frequency tACS modulation of MEPs was phase-dependent. Post hoc analyses suggested that this effect was specific to participants with low (<19 Hz) intrinsic beta frequency. In conclusion, by showing that beta tACS influences MEP amplitude in a phase-dependent manner, our results support a potential role attributed to neuronal oscillations in regulating corticospinal excitability. Moreover, our findings may be useful for the development of TMS protocols that improve the reliability of MEPs as a meaningful tool for research applications or for clinical monitoring and diagnosis. (C) 2018 Elsevier Ltd. All rights reserved.

Abstract

This study investigates whether or not the representation of lexical stress information can be primed during speech production. In four experiments, we attempted to prime the stress position of bisyllabic target nouns (picture names) having initial and final stress with auditory prime words having either the same or different stress as the target (e.g., WORtel–MOtor vs. koSTUUM–MOtor; capital letters indicate stressed syllables in prime–target pairs). Furthermore, half of the prime words were semantically related, the other half unrelated. Overall, picture names were not produced faster when the prime word had the same stress as the target than when the prime had different stress, i.e., there was no stress-priming effect in any experiment. This result would not be expected if stress were stored in the lexicon. However, targets with initial stress were responded to faster than final-stress targets. The reason for this effect was neither the quality of the pictures nor frequency of occurrence or voice-key characteristics. We hypothesize here that this stress effect is a genuine encoding effect, i.e., words with stress on the second syllable take longer to be encoded because their stress pattern is irregular with respect to the lexical distribution of bisyllabic stress patterns, even though it can be regular with respect to metrical stress rules in Dutch. The results of the experiments are discussed in the framework of models of phonological encoding.

Abstract

Any complete theory of speaking must take the dialogical function of language use into account. Pickering & Garrod (P&G) make some progress on this point. However, we question whether their interactive alignment model is the optimal approach. In this commentary, we specifically criticize (1) their notion of alignment being implemented through priming, and (2) their claim that self-monitoring can occur at all levels of linguistic representation.

Abstract

This study investigates whether or not masked form priming effects in the naming task depend on the number of shared segments between prime and target. Dutch participants named bisyllabic words, which were preceded by visual masked primes. When primes shared the initial segment(s) with the target, naming latencies were shorter than in a control condition (string of percent signs). Onset complexity (singleton vs. complex word onset) did not modulate this priming effect in Dutch. Furthermore, significant priming due to shared final segments was only found when the prime did not contain a mismatching onset, suggesting an interfering role of initial non-target segments. It is concluded that (a) degree of overlap (segmental match vs. mismatch), and (b) position of overlap (initial vs. final) influence the magnitude of the form priming effect in the naming task. A modification of the segmental overlap hypothesis (Schiller, 1998) is proposed to account for the data.

Abstract

Two experiments investigate the effect of number congruency using picture–word interference. Native German participants were required to name pictures of single objects (Nase ‘nose’) or two instances of the same object (Nasen ‘noses’) while ignoring simultaneously presented distractor words. Distractor words either had the same number or were different in number. In addition, the type of plural formation (same or different inflectional plural suffix) and the semantic relationship (same or different semantic category) between target and distractor were varied in Experiments 1 and 2. Results showed no effect of number congruency in either experiment. Furthermore, the type of inflectional suffix did not exert an influence on naming latencies in Experiment 1, but semantic relationship led to a significant interference effect in Experiment 2. The results indicate that selection of the number feature diacritic in noun production is not a competitive process. The implications of the results for models of lexical access are discussed.

Abstract

To investigate the role of the syllable in Dutch speech production, five experiments were carried out to examine the effect of visually masked syllable primes on the naming latencies for written words and pictures. Targets had clear syllable boundaries and began with a CV syllable (e.g., ka.no) or a CVC syllable (e.g., kak.tus), or had ambiguous syllable boundaries and began with a CV[C] syllable (e.g., ka[pp]er). In the syllable match condition, bisyllabic Dutch nouns or verbs were preceded by primes that were identical to the target’s first syllable. In the syllable mismatch condition, the prime was either shorter or longer than the target’s first syllable. A neutral condition was also included. None of the experiments showed a syllable priming effect. Instead, all related primes facilitated the naming of the targets. It is concluded that the syllable does not play a role in the process of phonological encoding in Dutch. Because the amount of facilitation increased with increasing overlap between prime and target, the priming effect is accounted for by a segmental overlap hypothesis.

Abstract

In language production research, the latency with which speakers produce a spoken response to a stimulus and the onset and offset times of words in longer utterances are key dependent variables. Measuring these variables automatically often yields partially incorrect results. However, exact measurements through the visual inspection of the recordings are extremely time-consuming. We present AlignTool, an open-source alignment tool that establishes preliminarily the onset and offset times of words and phonemes in spoken utterances using Praat, and subsequently performs a forced alignment of the spoken utterances and their orthographic transcriptions in the automatic speech recognition system MAUS. AlignTool creates a Praat TextGrid file for inspection and manual correction by the user, if necessary. We evaluated AlignTool’s performance with recordings of single-word and four-word utterances as well as semi-spontaneous speech. AlignTool performs well with audio signals with an excellent signal-to-noise ratio, requiring virtually no corrections. For audio signals of lesser quality, AlignTool still is highly functional but its results may require more frequent manual corrections. We also found that audio recordings including long silent intervals tended to pose greater difficulties for AlignTool than recordings filled with speech, which AlignTool analyzed well overall. We expect that by semi-automatizing the temporal analysis of complex utterances, AlignTool will open new avenues in language production research.

Abstract

Hoewel de spelling van Nederlandse verledentijdsvormen van zwakke werkwoorden algemeen als eenvoudig wordt beschouwd (ze zijn immers klankzuiver) maken zelfs universiteitsstudenten opvallend veel fouten bij de keuze tussen de uitgangen -te en -de. Voor een deel zijn die fouten ‘natuurlijk’ in die zin dat ze het gevolg zijn van de werking van frequentie en analogie. Anderzijds stellen we vast dat Nederlanders veel meer fouten maken dan Vlamingen, althans als de stam op een coronale fricatief eindigt (s, z, f, v). Aangezien de Nederlandse proefpersonen de ‘regel’ (het ezelsbruggetje ’t kofschip) beter lijken te beheersen dan de Vlamingen, moet de verklaring voor het verschil gezocht worden in een klankverandering die zich wel in Nederland maar niet of nauwelijks in Vlaanderen voordoet, de verstemlozing van de fricatieven. Het spellingprobleem vraagt om didactische maatregelen en/of politieke: het kan wellicht grotendeels worden opgelost door de spellingregels een weinig aan te passen.

Abstract

Although there is good evidence that social animals show elaborate cognitive skills to deal with others, there are few reports of animals physically using social agents and their respective responses as means to an end—social tool use. In this case study, we investigated spontaneous and repeated social tool use behavior in chimpanzees (Pan troglodytes). We presented a group of chimpanzees with an apparatus, in which pushing two buttons would release juice from a distantly located fountain. Consequently, any one individual could only either push the buttons or drink from the fountain but never push and drink simultaneously. In this scenario, an adult male attempted to retrieve three other individuals and push them toward the buttons that, if pressed, released juice from the fountain. With this strategy, the social tool user increased his juice intake 10-fold. Interestingly, the strategy was stable over time, which was possibly enabled by playing with the social tools. With over 100 instances, we provide the biggest data set on social tool use recorded among nonhuman animals so far. The repeated use of other individuals as social tools may represent a complex social skill linked to Machiavellian intelligence.

Abstract

Gender assignment relates to a native speaker's knowledge of the structure of the gender system of his/her language, allowing the speaker to select the appropriate gender for each noun. Whereas categorical assignment rules and exceptional gender assignment are well investigated, assignment regularities, i.e., tendencies in the gender distribution identified within the vocabulary of a language, are still controversial. The present study is an empirical contribution trying to shed light on the gender assignment system native German speakers have at their disposal. Participants presented with a category (e.g., predator) and a pair of gender-marked pseudowords (e.g., der Trelle vs. die Stisse) preferentially selected the pseudo-word preceded by the gender-marked determiner ‘‘associated’’ with the category (e.g., masculine). This finding suggests that semantic regularities might be part of the gender assignment system of native speakers.

Abstract

Representations learned by deep convolutional neural networks (CNNs) for object recognition are a widely
investigated model of the processing hierarchy in the human visual system. Using functional magnetic resonance
imaging, CNN representations of visual stimuli have previously been shown to correspond to processing stages in
the ventral and dorsal streams of the visual system. Whether this correspondence between models and brain
signals also holds for activity acquired at high temporal resolution has been explored less exhaustively. Here, we
addressed this question by combining CNN-based encoding models with magnetoencephalography (MEG).
Human participants passively viewed 1,000 images of objects while MEG signals were acquired. We modelled
their high temporal resolution source-reconstructed cortical activity with CNNs, and observed a feed-forward
sweep across the visual hierarchy between 75 and 200 ms after stimulus onset. This spatiotemporal cascade
was captured by the network layer representations, where the increasingly abstract stimulus representation in the
hierarchical network model was reflected in different parts of the visual cortex, following the visual ventral
stream. We further validated the accuracy of our encoding model by decoding stimulus identity in a left-out
validation set of viewed objects, achieving state-of-the-art decoding accuracy.

Abstract

Syntactic binding refers to combining words into larger structures. Using EEG, we investigated the neural processes involved in syntactic binding. Participants were auditorily presented two-word sentences (i.e. pronoun and pseudoverb such as ‘I grush’, ‘she grushes’, for which syntactic binding can take place) and wordlists (i.e. two pseudoverbs such as ‘pob grush’, ‘pob grushes’, for which no binding occurs). Comparing these two conditions, we targeted syntactic binding while minimizing contributions of semantic binding and of other cognitive processes such as working memory. We found a converging pattern of results using two distinct analysis approaches: one approach using frequency bands as defined in previous literature, and one data-driven approach in which we looked at the entire range of frequencies between 3-30 Hz without the constraints of pre-defined frequency bands. In the syntactic binding (relative to the wordlist) condition, a power increase was observed in the alpha and beta frequency range shortly preceding the presentation of the target word that requires binding, which was maximal over frontal-central electrodes. Our interpretation is that these signatures reflect that language comprehenders expect the need for binding to occur. Following the presentation of the target word in a syntactic binding context (relative to the wordlist condition), an increase in alpha power maximal over a left lateralized cluster of frontal-temporal electrodes was observed. We suggest that this alpha increase relates to syntactic binding taking place. Taken together, our findings suggest that increases in alpha and beta power are reflections of distinct the neural processes underlying syntactic binding.

Abstract

Behavioral syntactic priming effects during sentence comprehension are typically observed only if both the syntactic structure and lexical head are repeated. In contrast, during production syntactic priming occurs with structure repetition alone, but the effect is boosted by repetition of the lexical head. We used fMRI to investigate the neuronal correlates of syntactic priming and lexical boost effects during sentence production and comprehension. The critical measure was the magnitude of fMRI adaptation to repetition of sentences in active or passive voice, with or without verb repetition. In conditions with repeated verbs, we observed adaptation to structure repetition in the left IFG and MTG, for active and passive voice. However, in the absence of repeated verbs, adaptation occurred only for passive sentences. None of the fMRI adaptation effects yielded differential effects for production versus comprehension, suggesting that sentence comprehension and production are subserved by the same neuronal infrastructure for syntactic processing.

Abstract

Repetition suppression in fMRI studies is generally thought to underlie behavioural facilitation effects (i.e., priming) and it is often used to identify the neuronal representations associated with a stimulus. However, this pays little heed to the large number of repetition enhancement effects observed under similar conditions. In this review, we identify several cognitive variables biasing repetition effects in the BOLD response towards enhancement instead of suppression. These variables are stimulus recognition, learning, attention, expectation and explicit memory. We also evaluate which models can account for these repetition effects and come to the conclusion that there is no one single model that is able to embrace all repetition enhancement effects. Accumulation, novel network formation as well as predictive coding models can all explain subsets of repetition enhancement effects.

Abstract

This discussion note reviews responses of the linguistics profession to the grave issues of language
endangerment identified a quarter of a century ago in the journal Language by Krauss,
Hale, England, Craig, and others (Hale et al. 1992). Two and a half decades of worldwide research
not only have given us a much more accurate picture of the number, phylogeny, and typological
variety of the world’s languages, but they have also seen the development of a wide range of new
approaches, conceptual and technological, to the problem of documenting them. We review these
approaches and the manifold discoveries they have unearthed about the enormous variety of linguistic
structures. The reach of our knowledge has increased by about 15% of the world’s languages,
especially in terms of digitally archived material, with about 500 languages now
reasonably documented thanks to such major programs as DoBeS, ELDP, and DEL. But linguists
are still falling behind in the race to document the planet’s rapidly dwindling linguistic diversity,
with around 35–42% of the world’s languages still substantially undocumented, and in certain
countries (such as the US) the call by Krauss (1992) for a significant professional realignment toward
language documentation has only been heeded in a few institutions. Apart from the need for
an intensified documentarist push in the face of accelerating language loss, we argue that existing
language documentation efforts need to do much more to focus on crosslinguistically comparable
data sets, sociolinguistic context, semantics, and interpretation of text material, and on methods
for bridging the ‘transcription bottleneck’, which is creating a huge gap between the amount we
can record and the amount in our transcribed corpora.*

Abstract

We examined gesture representation of motion events in narratives produced by three- and nine-year-olds, and adults. Two aspects of gestural depiction were analysed: how protagonists were depicted, and how gesture space was used. We found that older groups were more likely to express protagonists as an object that a gesturing hand held and manipulated, and less likely to express protagonists with whole-body enactment gestures. Furthermore, for older groups, gesture space increasingly became less similar to narrated space. The older groups were less likely to use large gestures or gestures in the periphery of the gesture space to represent movements that were large relative to a protagonist’s body or that took place next to a protagonist. They were also less likely to produce gestures on a physical surface (e.g. table) to represent movement on a surface in narrated events. The development of gestural depiction indicates that older speakers become less immersed in the story world and start to control and manipulate story representation from an outside perspective in a bounded and stage-like gesture space. We discuss this developmental shift in terms of increasing symbolic distancing (Werner & Kaplan, 1963).

Abstract

Background: Gesture frequently accompanies speech in healthy speakers. For many individuals with aphasia, gestures are a target of speech-language pathology intervention, either as an alternative form of communication or as a facilitative device for language restoration. The patterns of gesture production for people with aphasia and the participant variables that predict these patterns remain unclear. Aims: We aimed to examine gesture production during conversational discourse in a large sample of individuals with aphasia. We used a detailed gesture coding system to determine patterns of gesture production associated with specific aphasia types and severities. Methods & Procedures: We analysed conversation samples from AphasiaBank, gathered from 46 people with post-stroke aphasia and 10 healthy matched controls all of whom had gestured at least once during a story re-tell task. Twelve gesture types were coded. Descriptive statistics were used to describe the patterns of gesture production. Possible significant differences in production patterns according to aphasia type and severity were examined with a series of analyses of variance (ANOVA) statistics, and multiple regression analysis was used to examine these potential predictors of gesture production patterns. Outcomes & Results: Individuals with aphasia gestured significantly more frequently than healthy controls. Aphasia type and severity impacted significantly on gesture type in specific identified patterns detailed here, especially on the production of meaning-laden gestures. Conclusions: These patterns suggest the opportunity for gestures as targets of aphasia therapy. Aphasia fluency accounted for a greater degree of data variability than aphasia severity or naming skills. More work is required to delineate predictive factors.

Abstract

Purpose For many individuals with aphasia, gestures form a vital component of message transfer and are the target of speech-language pathology intervention. What remains unclear are the participant variables that predict successful outcomes from gesture treatments. The authors examined the gesture production of a large number of individuals with aphasia—in a consistent discourse sampling condition and with a detailed gesture coding system—to determine patterns of gesture production associated with specific types of aphasia. Method The authors analyzed story retell samples from AphasiaBank (TalkBank, n.d.), gathered from 98 individuals with aphasia resulting from stroke and 64 typical controls. Twelve gesture types were coded. Descriptive statistics were used to describe the patterns of gesture production. Possible significant differences in production patterns according to aphasia type were examined using a series of chi-square, Fisher exact, and logistic regression statistics. Results A significantly higher proportion of individuals with aphasia gestured as compared to typical controls, and for many individuals with aphasia, this gesture was iconic and was capable of communicative load. Aphasia type impacted significantly on gesture type in specific identified patterns, detailed here. Conclusion These type-specific patterns suggest the opportunity for gestures as targets of aphasia therapy.

Abstract

This article discusses how the Trobriand Islanders speak about body and mind. It addresses the following questions: do the linguistic datafit into theories about lexical universals of body-part terminology? Can we make inferences about the Trobrianders' conceptualization of psychological and physical states on the basis of these data? If a Trobriand Islander sees these idioms as external manifestations of inner states, then can we interpret them as a kind of ethnopsychological theory about the body and its role for emotions, knowledge, thought, memory, and so on? Can these idioms be understood as representation of Trobriand ethnopsychological theory?

Abstract

A new sign language has been created by deaf Nicaraguans over the past 25 years, providing an opportunity to observe the inception of universal hallmarks of language. We found that in their initial creation of the language, children analyzed complex events into basic elements and sequenced these elements into hierarchically structured expressions according to principles not observed in gestures accompanying speech in the surrounding language. Successive cohorts of learners extended this procedure, transforming Nicaraguan signing from its early gestural form into a linguistic system. We propose that this early segmentation and recombination reflect mechanisms with which children learn, and thereby perpetuate, language. Thus, children naturally possess learning abilities capable of giving language its fundamental structure.

Abstract

The present study examined the relation between nonselective inhibition and selective inhibition in picture naming performance. Nonselective inhibition refers to the ability to suppress any unwanted response, whereas selective inhibition refers to the ability to suppress specific competing responses. The degree of competition in picture naming was manipulated by presenting targets along with distractor words that could be semantically related (e.g., a picture of a dog combined with the word cat) or unrelated (tree) to the picture name. The mean naming response time (RT) was longer in the related than in the unrelated condition, reflecting semantic interference. Delta plot analyses showed that participants with small mean semantic interference effects employed selective inhibition more effectively than did participants with larger semantic interference effects. The participants were also tested on the stop-signal task, which taps nonselective inhibition. Their performance on this task was correlated with their mean naming RT but, importantly, not with the selective inhibition indexed by the delta plot analyses and the magnitude of the semantic interference effect. These results indicate that nonselective inhibition ability and selective inhibition of competitors in picture naming are separable to some extent.

Abstract

Models of speech production disagree on whether or not homonyms have a shared word-form representation. To investigate this issue, a picture-naming experiment was carried out using Dutch homonyms of which both meanings could be presented as a picture. Naming latencies for the low-frequency meanings of homonyms were slower than for those of the high-frequency meanings. However, no frequency effect was found for control words, which matched the frequency of the homonyms meanings. Subsequent control experiments indicated that the difference in naming latencies for the homonyms could be attributed to processes earlier than wordform retrieval. Specifically, it appears that low name agreement slowed down the naming of the low-frequency homonym pictures.

Abstract

Since Pillsbury [1908. Attention. London: Swan Sonnenschein & Co], the issue of whether attention operates through inhibition or enhancement has been on the scientific agenda. We examined whether overcoming previous attentional inhibition or enhancement is the source of asymmetrical switch costs in spoken noun-phrase production and colour-word Stroop tasks. In Experiment 1, using bivalent stimuli, we found asymmetrical costs in response times for switching between long and short phrases and between Stroop colour naming and reading. However, in Experiment 2, using bivalent stimuli for the weaker tasks (long phrases, colour naming) and univalent stimuli for the stronger tasks (short phrases, word reading), we obtained an asymmetrical switch cost for phrase production, but a symmetrical cost for Stroop. The switch cost evidence was quantified using Bayesian statistical analyses. Our findings suggest that switching between phrase types involves inhibition, whereas switching between colour naming and reading involves enhancement. Thus, the attentional mechanism depends on the language-production task involved. The results challenge theories of task switching that assume only one attentional mechanism, inhibition or enhancement, rather than both mechanisms.

Abstract

Recently, it has been proposed that sequence learning engages a combination of modality-specific operating networks and modality-independent computational principles. In the present study, we compared the behavioural and EEG outcomes of implicit artificial grammar learning in the visual vs. auditory modality. We controlled for the influence of surface characteristics of sequences (Associative Chunk Strength), thus focusing on the strictly structural aspects of sequence learning, and we adapted the paradigms to compensate for known frailties of the visual modality compared to audition (temporal presentation, fast presentation rate). The behavioural outcomes were similar across modalities. Favouring the idea of modality-specificity, ERPs in response to grammar violations differed in topography and latency (earlier and more anterior component in the visual modality), and ERPs in response to surface features emerged only in the auditory modality. In favour of modality-independence, we observed three common functional properties in the late ERPs of the two grammars: both were free of interactions between structural and surface influences, both were more extended in a grammaticality classification test than in a preference classification test, and both correlated positively and strongly with theta event-related-synchronization during baseline testing. Our findings support the idea of modality-specificity combined with modality-independence, and suggest that memory for visual vs. auditory sequences may largely contribute to cross-modal differences.

Abstract

Perceptual compensation for speaker vocal tract properties was investigated in four groups of listeners: native speakers of English and native speakers of Dutch, native speakers of Spanish with low proficiency in English, and Spanish-English bilinguals. Listeners categorized targets on a [sofo] to [sufu] continuum. Targets were preceded by sentences that were manipulated to have either a high or a low F1 contour. All listeners performed the categorization task for targets that were preceded by Spanish, English and Dutch precursors. Results show that listeners from each of the four language backgrounds compensate for speaker vocal tract properties regardless of language-specific vowel inventory properties. Listeners also compensate when they listen to stimuli in another language. The results suggest that patterns of compensation are mainly determined by auditory properties of precursor sentences.

Abstract

One of the important challenges for the development of science communication concerns the current problems with the under-exposure of null results. I suggest that each article published in a top scientific journal can get tagged (online) with attempts to replicate. As such, a future reader of an article will also be able to see whether replications have been attempted and how these turned out. Editors and/or reviewers decide whether a replication is of sound quality. The authors of the main article have the option to review the replication and can provide a supplementary comment with each attempt that is added. After 5 or 10 years, and provided enough attempts to replicate, the authors of the main article get the opportunity to discuss/review their original study in light of the outcomes of the replications. This approach has two important strengths: 1) The approach would provide researchers with the opportunity to show that they deliver scientifically thorough work, but sometimes just fail to replicate the result that others have reported. This can be especially valuable for the career opportunities of promising young researchers; 2) perhaps even more important, the visibility of replications provides an important incentive for researchers to publish findings only if they are sure that their effects are reliable (and thereby reduce the influence of "experimenter degrees of freedom" or even outright fraud). The proposed approach will stimulate researchers to look beyond the point of publication of their studies.

Abstract

Important speech cues such as lexical tone and vowel quality are perceptually contrasted to the distribution of those same cues in surrounding contexts. However, it is unclear whether preceding and following contexts have similar influences, and to what extent those influences are modulated by the auditory history of previous trials. To investigate this, Cantonese participants labeled sounds from (a) a tone continuum (mid- to high-level), presented with a context that had raised or lowered F0 values and (b) a vowel quality continuum (/u/ to /o/), where the context had raised or lowered F1 values. Contexts with high or low F0/F1 were presented in separate blocks or intermixed in 1 block. Contexts were presented following (Experiment 1) or preceding the target continuum (Experiment 2). Contrastive effects were found for both tone and vowel quality (e.g., decreased F0 values in contexts lead to more high tone target judgments and vice versa). Importantly, however, lexical tone was only influenced by F0 in immediately preceding and following contexts. Vowel quality was only influenced by the F1 in preceding contexts, but this extended to contexts from preceding trials. Contextual influences on tone and vowel quality are qualitatively different, which has important implications for understanding the mechanism of context effects in speech perception.

Abstract

Three experiments investigated whether extrinsic vowel normalization takes place largely at a categorical or a precategorical level of processing. Traditional vowel normalization effects in categorization were replicated in Experiment 1: Vowels taken from an [ɪ]-[ε] continuum were more often interpreted as /ɪ/ (which has a low first formant, F (1)) when the vowels were heard in contexts that had a raised F (1) than when the contexts had a lowered F (1). This was established with contexts that consisted of only two syllables. These short contexts were necessary for Experiment 2, a discrimination task that encouraged listeners to focus on the perceptual properties of vowels at a precategorical level. Vowel normalization was again found: Ambiguous vowels were more easily discriminated from an endpoint [ε] than from an endpoint [ɪ] in a high-F (1) context, whereas the opposite was true in a low-F (1) context. Experiment 3 measured discriminability between pairs of steps along the [ɪ]-[ε] continuum. Contextual influences were again found, but without discrimination peaks, contrary to what was predicted from the same participants' categorization behavior. Extrinsic vowel normalization therefore appears to be a process that takes place at least in part at a precategorical processing level.

Abstract

Young children's visual environments are dynamic, changing moment-by-moment as children physically and visually explore spaces and objects and interact with people around them. Head-mounted eye tracking offers a unique opportunity to capture children's dynamic egocentric views and how they allocate visual attention within those views. This protocol provides guiding principles and practical recommendations for researchers using head-mounted eye trackers in both laboratory and more naturalistic settings. Head-mounted eye tracking complements other experimental methods by enhancing opportunities for data collection in more ecologically valid contexts through increased portability and freedom of head and body movements compared to screen-based eye tracking. This protocol can also be integrated with other technologies, such as motion tracking and heart-rate monitoring, to provide a high-density multimodal dataset for examining natural behavior, learning, and development than previously possible. This paper illustrates the types of data generated from head-mounted eye tracking in a study designed to investigate visual attention in one natural context for toddlers: free-flowing toy play with a parent. Successful use of this protocol will allow researchers to collect data that can be used to answer questions not only about visual attention, but also about a broad range of other perceptual, cognitive, and social skills and their development.

Abstract

Attention-deficit/hyperactivity disorder (ADHD) is the most commonly diagnosed behavioral disorder in childhood and likely represents an extreme of normal behavior. ADHD significantly impacts learning in school-age children and leads to impaired functioning throughout the life span. There is strong evidence for a genetic etiology of the disorder, although putative alleles, principally in dopamine-related pathways suggested by candidate-gene studies, have very small effect sizes. We use affected-sib-pair analysis in 203 families to localize the first major susceptibility locus for ADHD to a 12-cM region on chromosome 16p13 (maximum LOD score 4.2; P=.000005), building upon an earlier genomewide scan of this disorder. The region overlaps that highlighted in three genome scans for autism, a disorder in which inattention and hyperactivity are common, and physically maps to a 7-Mb region on 16p13. These findings suggest that variations in a gene on 16p13 may contribute to common deficits found in both ADHD and autism.

Abstract

Abstract In the past, several assessment reports on writing repeatedly showed that elementary school students do not develop the essential writing skills to be successful in school. In this respect, prior research has pointed to the fact that cognitive and motivational challenges are at the root of the rather basic level of elementary students' writing performance. Additionally, previous research has revealed gender and achievement-level differences in elementary students' writing. In view of providing effective writing instruction for all students to overcome writing difficulties, the present study provides more in-depth insight into (a) how cognitive and motivational challenges mediate and correlate with students' writing performance and (b) whether and how these relations vary for boys and girls and for writers of different achievement levels. In the present study, 1,577 fifth- and sixth-grade students completed questionnaires regarding their writing self-efficacy, writing motivation, and writing strategies. In addition, half of the students completed two writing tests, respectively focusing on the informational or narrative text genre. Based on multiple group structural equation modeling (MG-SEM), we put forward two models: a MG-SEM model for boys and girls and a MG-SEM model for low, average, and high achievers. The results underline the importance of studying writing models for different groups of students in order to gain more refined insight into the complex interplay between motivational and cognitive challenges related to students' writing performance.

Abstract

Language-mediated visual attention describes the interaction of two fundamental components of the human cognitive system, language and vision. Within this paper we present an amodal shared resource model of language-mediated visual attention that offers a description of the information and processes involved in this complex multimodal behavior and a potential explanation for how this ability is acquired. We demonstrate that the model is not only sufficient to account for the experimental effects of Visual World Paradigm studies but also that these effects are emergent properties of the architecture of the model itself, rather than requiring separate information processing channels or modular processing systems. The model provides an explicit description of the connection between the modality-specific input from language and vision and the distribution of eye gaze in language-mediated visual attention. The paper concludes by discussing future applications for the model, specifically its potential for investigating the factors driving observed individual differences in language-mediated eye gaze.

Abstract

A quantitative model of human categorization behavior is proposed, which can be applied to 4-alternative forced-choice categorization data involving two binary classifications. A number of processing dependencies between the two classifications are explicitly formulated, such as the dependence of the location, orientation, and steepness of the class boundary for one classification on the outcome of the other classification. The significance of various types of dependencies can be tested statistically. Analyses of a data set from the literature shows that interesting dependencies in human speech recognition can be uncovered using the model.

Abstract

The appropriate definition and scaling of the magnitude of electroencephalogram (EEG) oscillations is an underdeveloped area. The aim of this study was to optimize the analysis of resting EEG alpha magnitude, focusing on alpha peak frequency and nonlinear transformation of alpha power. A family of nonlinear transforms, Box-Cox transforms, were applied to find the transform that (a) maximized a non-disputed effect: the increase in alpha magnitude when the eyes are closed (Berger effect), and (b) made the distribution of alpha magnitude closest to normal across epochs within each participant, or across participants. The transformations were performed either at the single epoch level or at the epoch-average level. Alpha peak frequency showed large individual differences, yet good correspondence between various ways to estimate it in 2min of eyes-closed and 2min of eyes-open resting EEG data. Both alpha magnitude and the Berger effect were larger for individual alpha than for a generic (8-12Hz) alpha band. The log-transform on single epochs (a) maximized the t-value of the contrast between the eyes-open and eyes-closed conditions when tested within each participant, and (b) rendered near-normally distributed alpha power across epochs and participants, thereby making further transformation of epoch averages superfluous. The results suggest that the log-normal distribution is a fundamental property of variations in alpha power across time in the order of seconds. Moreover, effects on alpha power appear to be multiplicative rather than additive. These findings support the use of the log-transform on single epochs to achieve appropriate scaling of alpha magnitude.

Abstract

Atypical visual perception in people with autism spectrum disorders (ASD) is hypothesized to stem from an imbalance in excitatory and inhibitory processes in the brain. We used neuronal oscillations in the gamma frequency range (30 – 90 Hz), which emerge from a balanced interaction of excitation and inhibition in the brain, to assess contextual modulation processes in early visual perception. Electroencephalography was recorded in 12 high-functioning adults with ASD and 12 age- and IQ-matched control participants. Oscilla- tions in the gamma frequency range were analyzed in response to stimuli consisting of small line-like elements. Orientation-speci fi c contextual modulation was manipulated by parametrically increasing the amount of homogeneously oriented elements in the stimuli. The stimuli elicited a strong steady-state gamma response around the refresh-rate of 60 Hz, which was larger for controls than for participants with ASD. The amount of orientation homogeneity (contextual modulation) in fl uenced the gamma response in control subjects, while for subjects with ASD this was not the case. The atypical steady-state gamma response to contextual modulation in subjects with ASD may capture the link between an imbalance in excitatory and inhibitory neuronal processing and atypical visual processing in ASD

Abstract

Chromatin remodeling is of crucial importance during brain development. Pathogenic
alterations of several chromatin remodeling ATPases have been implicated in neurodevelopmental
disorders. We describe an index case with a de novo missense mutation in CHD3,
identified during whole genome sequencing of a cohort of children with rare speech disorders.
To gain a comprehensive view of features associated with disruption of this gene, we use a
genotype-driven approach, collecting and characterizing 35 individuals with de novo CHD3
mutations and overlapping phenotypes. Most mutations cluster within the ATPase/helicase
domain of the encoded protein. Modeling their impact on the three-dimensional structure
demonstrates disturbance of critical binding and interaction motifs. Experimental assays with
six of the identified mutations show that a subset directly affects ATPase activity, and all but
one yield alterations in chromatin remodeling. We implicate de novo CHD3 mutations in a
syndrome characterized by intellectual disability, macrocephaly, and impaired speech and
language.

Abstract

Many genetic causes of developmental delay and/or intellectual disability (DD/ID) are extremely rare, and robust discovery of these requires both large-scale DNA sequencing and data sharing. Here we describe a GeneMatcher collaboration which led to a cohort of 13 affected individuals harboring protein-altering variants, 11 of which are de novo, in MED13; the only inherited variant was transmitted to an affected child from an affected mother. All patients had intellectual disability and/or developmental delays, including speech delays or disorders. Other features that were reported in two or more patients include autism spectrum disorder, attention deficit hyperactivity disorder, optic nerve abnormalities, Duane anomaly, hypotonia, mild congenital heart abnormalities, and dysmorphisms. Six affected individuals had mutations that are predicted to truncate the MED13 protein, six had missense mutations, and one had an in-frame-deletion of one amino acid. Out of the seven non-truncating mutations, six clustered in two specific locations of the MED13 protein: an N-terminal and C-terminal region. The four N-terminal clustering mutations affect two adjacent amino acids that are known to be involved in MED13 ubiquitination and degradation, p.Thr326 and p.Pro327. MED13 is a component of the CDK8-kinase module that can reversibly bind Mediator, a multi-protein complex that is required for Polymerase II transcription initiation. Mutations in several other genes encoding subunits of Mediator have been previously shown to associate with DD/ID, including MED13L, a paralog of MED13. Thus, our findings add MED13 to the group of CDK8-kinase module-associated disease genes

Abstract

Do we mentally simulate olfactory information? We investigated mental simulation of odors and sounds in two experiments. Participants retained a word while they smelled an odor or heard a sound, then rated odor/sound intensity and recalled the word. Later odor/sound recognition was also tested, and pleasantness and familiarity judgments were collected. Word recall was slower when the sound and sound-word mismatched (e.g., bee sound with the word typhoon). Sound recognition was higher when sounds were paired with a match or near-match word (e.g., bee sound with bee or buzzer). This indicates sound-words are mentally simulated. However, using the same paradigm no memory effects were observed for odor. Instead it appears odor-words only affect lexical-semantic representations, demonstrated by higher ratings of odor intensity and pleasantness when an odor was paired with a match or near-match word (e.g., peach odor with peach or mango). These results suggest fundamental differences in how odor and sound-words are represented.

Abstract

Olfaction is often considered a vestigial sense in humans, demoted throughout evolution to make way for the dominant sense of vision. This perspective on olfaction is reflected in how we think and talk about smells in the West, with odor imagery and odor language reported to be difficult. In the present study we demonstrate odor cognition is superior in odor-color synaesthesia, where there are additional sensory connections to odor concepts. Synaesthesia is a neurological phenomenon in which input in 1 modality leads to involuntary perceptual associations. Semantic accounts of synaesthesia posit synaesthetic associations are mediated by activation of inducing concepts. Therefore, synaesthetic associations may strengthen conceptual representations. To test this idea, we ran 6 odor-color synaesthetes and 17 matched controls on a battery of tasks exploring odor and color cognition. We found synaesthetes outperformed controls on tests of both odor and color discrimination, demonstrating for the first time enhanced perception in both the inducer (odor) and concurrent (color) modality. So, not only do synaesthetes have additional perceptual experiences in comparison to controls, their primary perceptual experience is also different. Finally, synaesthetes were more consistent and accurate at naming odors. We propose synaesthetic associations to odors strengthen odor concepts, making them more differentiated (facilitating odor discrimination) and easier to link with lexical representations (facilitating odor naming). In summary, we show for the first time that both odor language and perception is enhanced in people with synaesthetic associations to odors

Abstract

Spoken word recognition involves automatic activation of lexical candidates compatible with the perceived input. In running speech, words abut one another without intervening gaps, and syllable boundaries can mismatch with word boundaries. For instance, liaison in ’petit agneau’ creates a syllable beginning with a consonant although ’agneau’ begins with a vowel. In two cross-modal priming experiments we investigate how French listeners recognise words in liaison environments. These results suggest that the resolution of liaison in part depends on acoustic cues which distinguish liaison from non-liaison consonants, and in part on the availability of lexical support for a liaison interpretation.

Abstract

The response exclusion account (REA), advanced by Mahon and colleagues, localises the distractor frequency effect and the semantic interference effect in picture naming at the level of the response output buffer. We derive four predictions from the REA: (1) the size of the distractor frequency effect should be identical to the frequency effect obtained when distractor words are read aloud, (2) the distractor frequency effect should not change in size when stimulus-onset asynchrony (SOA) is manipulated, (3) the interference effect induced by a distractor word (as measured from a nonword control distractor) should increase in size with increasing SOA, and (4) the word frequency effect and the semantic interference effect should be additive. The results of the picture-naming task in Experiment 1 and the word-reading task in Experiment 2 refute all four predictions. We discuss a tentative account of the findings obtained within a traditional selection-by-competition model in which both context effects are localised at the level of lexical selection.

Abstract

Neuronal nicotinic acetylcholine receptor (nAChR) genes (CHRNA5/CHRNA3/CHRNB4) have been reproducibly associated with nicotine dependence, smoking behaviors, and lung cancer risk. Of the few reports that have focused on early smoking behaviors, association results have been mixed. This meta-analysis examines early smoking phenotypes and SNPs in the gene cluster to determine: (1) whether the most robust association signal in this region (rs16969968) for other smoking behaviors is also associated with early behaviors, and/or (2) if additional statistically independent signals are important in early smoking. We focused on two phenotypes: age of tobacco initiation (AOI) and age of first regular tobacco use (AOS). This study included 56,034 subjects (41 groups) spanning nine countries and evaluated five SNPs including rs1948, rs16969968, rs578776, rs588765, and rs684513. Each dataset was analyzed using a centrally generated script. Meta-analyses were conducted from summary statistics. AOS yielded significant associations with SNPs rs578776 (beta = 0.02, P = 0.004), rs1948 (beta = 0.023, P = 0.018), and rs684513 (beta = 0.032, P = 0.017), indicating protective effects. There were no significant associations for the AOI phenotype. Importantly, rs16969968, the most replicated signal in this region for nicotine dependence, cigarettes per day, and cotinine levels, was not associated with AOI (P = 0.59) or AOS (P = 0.92). These results provide important insight into the complexity of smoking behavior phenotypes, and suggest that association signals in the CHRNA5/A3/B4 gene cluster affecting early smoking behaviors may be different from those affecting the mature nicotine dependence phenotype

Abstract

The principle of common coding suggests that a joint representation is formed when actions are repeatedly paired with a specific perceptual event. Musicians are occupationally specialized with regard to the coupling between actions and their auditory effects. In the present study, we employed a novel paradigm to demonstrate automatic action–effect associations in pianists. Pianists and nonmusicians pressed keys according to aurally presented number sequences. Numbers were presented at pitches that were neutral, congruent, or incongruent with respect to pitches that would normally be produced by such actions. Response time differences were seen between congruent and incongruent sequences in pianists alone. A second experiment was conducted to determine whether these effects could be attributed to the existence of previously documented spatial/pitch compatibility effects. In a “stretched” version of the task, the pitch distance over which the numbers were presented was enlarged to a range that could not be produced by the hand span used in Experiment 1. The finding of a larger response time difference between congruent and incongruent trials in the original, standard, version compared with the stretched version, in pianists, but not in nonmusicians, indicates that the effects obtained are, at least partially, attributable to learned action effects.

Abstract

Relying on the methodology of conversation analysis, this article examines a practice in ordinary conversation characterized by the resaying of a word, phrase, or sentence. The article shows that multiple sayings such as "No no no" or "Alright alright alright" are systematic in both their positioning relative to the interlocutor's talk and in their function. Specifically, the findings are that multiple sayings are a resource speakers have to display that their turn is addressing an in progress course of action rather than only the just prior utterance. Speakers of multiple sayings communicate their stance that the prior speaker has persisted unnecessarily in the prior course of action and should properly halt course of action.

Abstract

This study assesses the effects of age and language exposure on VOT production in 29 simultaneous bilingual children aged 3;7 to 5;11 who speak German as a heritage language in the Netherlands. Dutch and German have a binary voicing contrast, but the contrast is implemented with different VOT values in the two languages. The results suggest that bilingual children produce ‘voiced’ plosives similarly in their two languages, and these productions are not monolingual-like in either language. Bidirectional cross-linguistic influence between Dutch and German can explain these results. Yet, the bilinguals seemingly have two autonomous categories for Dutch and German ‘voiceless’ plosives. In German, the bilinguals’ aspiration is not monolingual-like, but bilinguals with more heritage language exposure produce more target-like aspiration. Importantly, the amount of exposure to German has no effect on the majority language's ‘voiceless’ category. This implies that more heritage language exposure is associated with more language-specific voicing systems.

Abstract

Human intracranial electroencephalography (iEEG) recordings provide data with much greater spatiotemporal precision
than is possible from data obtained using scalp EEG, magnetoencephalography (MEG), or functional MRI. Until recently,
the fusion of anatomical data (MRI and computed tomography (CT) images) with electrophysiological data and their
subsequent analysis have required the use of technologically and conceptually challenging combinations of software.
Here, we describe a comprehensive protocol that enables complex raw human iEEG data to be converted into more readily
comprehensible illustrative representations. The protocol uses an open-source toolbox for electrophysiological data
analysis (FieldTrip). This allows iEEG researchers to build on a continuously growing body of scriptable and reproducible
analysis methods that, over the past decade, have been developed and used by a large research community. In this
protocol, we describe how to analyze complex iEEG datasets by providing an intuitive and rapid approach that can handle
both neuroanatomical information and large electrophysiological datasets. We provide a worked example using
an example dataset. We also explain how to automate the protocol and adjust the settings to enable analysis of
iEEG datasets with other characteristics. The protocol can be implemented by a graduate student or postdoctoral
fellow with minimal MATLAB experience and takes approximately an hour to execute, excluding the automated cortical
surface extraction.

Abstract

Human referential communication is often thought as coding-decoding a set of symbols, neglecting that establishing shared meanings requires a computational mechanism powerful enough to mutually negotiate them. Sharing the meaning of a novel symbol might rely on similar conceptual inferences across communicators or on statistical similarities in their sensorimotor behaviors. Using magnetoencephalography, we assess spectral, temporal, and spatial characteristics of neural activity evoked when people generate and understand novel shared symbols during live communicative interactions. Solving those communicative problems induced comparable changes in the spectral profile of neural activity of both communicators and addressees. This shared neuronal up-regulation was spatially localized to the right temporal lobe and the ventromedial prefrontal cortex and emerged already before the occurrence of a specific communicative problem. Communicative innovation relies on neuronal computations that are shared across generating and understanding novel shared symbols, operating over temporal scales independent from transient sensorimotor behavior.

Abstract

Magnetoencephalography (MEG) is measured above the head, which makes it sensitive to variations of the head position with respect to the sensors. Head movements blur the topography of the neuronal sources of the MEG signal, increase localization errors, and reduce statistical sensitivity. Here we describe two novel and readily applicable methods that compensate for the detrimental effects of head motion on the statistical sensitivity of MEG experiments. First, we introduce an online procedure that continuously monitors head position. Second, we describe an offline analysis method that takes into account the head position time-series. We quantify the performance of these methods in the context of three different experimental settings, involving somatosensory, visual and auditory stimuli, assessing both individual and group-level statistics. The online head localization procedure allowed for optimal repositioning of the subjects over multiple sessions, resulting in a 28% reduction of the variance in dipole position and an improvement of up to 15% in statistical sensitivity. Offline incorporation of the head position time-series into the general linear model resulted in improvements of group-level statistical sensitivity between 15% and 29%. These tools can substantially reduce the influence of head movement within and between sessions, increasing the sensitivity of many cognitive neuroscience experiments.

Abstract

As participants repeatedly interact using graphical signals (as in a game of Pictionary), the signals gradually shift from being iconic (or motivated) to being symbolic (or arbitrary). The aim here is to test experimentally whether this change in the form of the signal implies a concomitant shift in the inferential mechanisms needed to understand it. The results show that, during early, iconic stages, there is more reliance on creative inferential processes associated with insight problem solving, and that the recruitment of these cognitive mechanisms decreases over time. The variation in inferential mechanism is not predicted by the sign’s visual complexity or iconicity, but by its familiarity, and by the complexity of the relevant mental representations. The discussion explores implications for pragmatics, language evolution, and iconicity research.

Abstract

This study investigates whether spoken sentence comprehension deficits in Broca's aphasics results from their inability to access the subordinate meaning of ambiguous words (e.g. bank), or alternatively, from a delay in their selection of the contextually appropriate meaning. Twelve Broca's aphasics and twelve elderly controls were presented with lexical ambiguities in three context conditions, each followed by the same target words. In the concordant condition, the sentence context biased the meaning of the sentence final ambiguous word that was related to the target. In the discordant condition, the sentence context biased the meaning of the sentence final ambiguous word that was incompatible with the target.In the unrelated condition, the sentence-final word was unambiguous and unrelated to the target. The task of the subjects was to listen attentively to the stimuli The activational status of the ambiguous sentence-final words was inferred from the amplitude of the N399 to the targets at two inter-stimulus intervals (ISIs) (100 ms and 1250 ms). At the short ISI, the Broca's aphasics showed clear evidence of activation of the subordinate meaning. In contrast to elderly controls, however, the Broca's aphasics were not successful at selecting the appropriate meaning of the ambiguity in the short ISI version of the experiment. But at the long ISI, in accordance with the performance of the elderly controls, the patients were able to successfully complete the contextual selection process. These results indicate that Broca's aphasics are delayed in the process of contextual selection. It is argued that this finding of delayed selection is compatible with the idea that comprehension deficits in Broca's aphasia result from a delay in the process of integrating lexical information.

Abstract

This volume on Inuit speech follows the evolution of a native language of the North American Arctic, from its historical roots to its present-day linguistic structure and patterns of use from Alaska to Greenland. Drawing on a wide range of research from the fields of linguistics, anthropology, and sociology, Dorais integrates these diverse perspectives in a comprehensive view of native language development, maintenance, and use under conditions of marginalization due to social transition.

Abstract

Three experiments tested young children's efficiency in recognizing words in speech referring to absent objects. Seventy-two 24-month-olds heard sentences containing target words denoting objects that were or were not present in a visual display. Children's eye movements were monitored as they heard the sentences. Three distinct patterns of response were shown. Children hearing a familiar word that was an appropriate label for the currently fixated picture maintained their gaze. Children hearing a familiar word that could not apply to the currently fixated picture rapidly shifted their gaze to the alternative picture, whether that alternative was the named target or not, and then continued to search for an appropriate referent. Finally, children hearing an unfamiliar word shifted their gaze slowly and irregularly. This set of outcomes is interpreted as evidence that by 24 months, rapid activation in word recognition does not depend on the presence of the words' referents. Rather, very young children are capable of quickly and efficiently interpreting words in the absence of visual supporting context.

Abstract

The degree to which infants represent phonetic detail in words has been a source of controversy in phonology and developmental psychology. One prominent hypothesis holds that infants store words in a vague or inaccurate form until the learning of similar–sounding neighbors forces attention to subtle phonetic distinctions. In the experiment reported here, we used a visual fixation task to assess word recognition. We present the first evidence indicating that, in fact, the lexical representations of 14– and 15–month–olds are encoded in fine detail, even when this detail is not functionally necessary for distinguishing similar words in the infant’s vocabulary. Exposure to words is sufficient for well–specified lexical representations, even well before the vocabulary spurt. These results suggest developmental continuity in infants’ representations of speech: As infants begin to build a vocabulary and learn word meanings, they use the perceptual abilities previously demonstrated in tasks testing the discrimination and categorization of meaningless syllables.

Abstract

The roles which word class (open/closed) and sentential stress play in the sentence comprehension processes of both agrammatic (Broca's) aphasics and normal listeners were examined with a word monitoring task. Overall, normal listeners responded more quickly to stressed than to unstressed items, but showed no effect of word class. Aphasics also responded more quickly to stressed than to unstressed materials, but, unlike the normals, responded faster to open than to closed class words regardless of their stress. The results are interpreted as support for the theory that Broca's aphasics lack the functional underlying open/closed class word distinction used in word recognition by normal listeners.

Abstract

We investigate the emergence of iconicity, specifically a bouba-kiki effect in miniature artificial languages under different functional constraints: when the languages are reproduced and when they are used communicatively. We ran transmission chains of (a) participant dyads who played an interactive communicative game and (b) individual participants who played a matched learning game. An analysis of the languages over six generations in an iterated learning experiment revealed that in the Communication condition, but not in the Reproduction condition, words for spiky shapes tend to be rated by naive judges as more spiky than the words for round shapes. This suggests that iconicity may not only be the outcome of innovations introduced by individuals, but, crucially, the result of interlocutor negotiation of new communicative conventions. We interpret our results as an illustration of cultural evolution by random mutation and selection (as opposed to by guided variation).