Publications

Abstract

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

Abstract

Oral communication often takes place in noisy environments, which challenge spoken-word recognition. Previous research has suggested that the presence of background noise extends the number of candidate words competing with the target word for recognition and that this extension affects the time course and accuracy of spoken-word recognition. In this study, we further investigated the temporal dynamics of competition processes in the presence of background noise, and how these vary in listeners with different language proficiency (i.e., native and non-native) using computational modeling. We developed ListenIN (Listen-In-Noise), a neural-network model based on an autoencoder architecture, which learns to map phonological forms onto meanings in two languages and simulates native and non-native spoken-word comprehension. Simulation A established that ListenIN captures the effects of noise on accuracy rates and the number of unique misperception errors of native and non-native listeners in an offline spoken-word identification task (Scharenborg et al., 2018). Simulation B showed that ListenIN captures the effects of noise in online task settings and accounts for looking preferences of native (Hintz & Scharenborg, 2016) and non-native (new data collected for this study) listeners in a visual-world paradigm. We also examined the model’s activation states during online spoken-word recognition. These analyses demonstrated that the presence of background noise increases the number of competitor words which are engaged in phonological competition and that this happens in similar ways intra- and interlinguistically and in native and non-native listening. Taken together, our results support accounts positing a ‘many-additional-competitors scenario’ for the effects of noise on spoken-word recognition.

Abstract

Developmental stuttering is a fluency disorder that adversely affect many aspects of a person's life. Recent transcranial direct current stimulation (tDCS) studies have shown promise to improve fluency in people who stutter. To date, bihemispheric tDCS has not been investigated in this population. In the present study, we aimed to investigate the effects of single-session bihemispheric and unihemispheric cathodal tDCS on fluency in adults who stutter. We predicted that bihemispheric tDCS with anodal stimulation to the left IFG and cathodal stimulation to the right IFG would improve fluency better than the sham and cathodal tDCS to the right IFG. Seventeen adults who stutter completed this single-blind, crossover, sham-controlled tDCS experiment. All participants received 20 min of tDCS alongside metronome-timed speech during intervention sessions. Three tDCS interventions were administered: bihemispheric tDCS with anodal stimulation to the left IFG and cathodal stimulation to the right IFG, unihemispheric tDCS with cathodal stimulation to the right IFG, and sham stimulation. Speech fluency during reading and conversation was assessed before, immediately after, and one week after each intervention session. There was no significant fluency improvement in conversation for any tDCS interventions. Reading fluency improved following both bihemispheric and cathodal tDCS interventions. tDCS montages were not significantly different in their effects on fluency.

Abstract

The COVID-19 pandemic, and the resulting closure of daycare centers worldwide, led to unprecedented changes in children’s learning environments. This period of increased time at home with caregivers, with limited access to external sources (e.g., daycares) provides a unique opportunity to examine the associations between the caregiver-child activities and children’s language development. The vocabularies of 1742 children aged8-36 months across 13 countries and 12 languages were evaluated at the beginning and end of the first lockdown period in their respective countries(from March to September 2020). Children who had less passive screen exposure and whose caregivers read more to them showed larger gains in vocabulary development during lockdown, after controlling for SES and other caregiver-child activities. Children also gained more words than expected (based on normative data) during lockdown; either caregivers were more aware of their child’s development or vocabulary development benefited from intense caregiver-child interaction during lockdown.

Abstract

Transcranial alternating current stimulation (tACS) at 10 Hz has been shown to modulate spatial attention. However, the frequency-specificity and the oscillatory changes underlying this tACS effect are still largely unclear. Here, we applied high-definition tACS at individual alpha frequency (IAF), two control frequencies (IAF+/-2Hz) and sham to the left posterior parietal cortex and measured its effects on visuospatial attention performance and offline alpha power (using electroencephalography, EEG). We revealed a behavioural and electrophysiological stimulation effect relative to sham for IAF but not control frequency stimulation conditions: there was a leftward lateralization of alpha power for IAF tACS, which differed from sham for the first out of three minutes following tACS. At a high value of this EEG effect (moderation effect), we observed a leftward attention bias relative to sham. This effect was task-specific, i.e., it could be found in an endogenous attention but not in a detection task. Only in the IAF tACS condition, we also found a correlation between the magnitude of the alpha lateralization and the attentional bias effect. Our results support a functional role of alpha oscillations in visuospatial attention and the potential of tACS to modulate it. The frequency-specificity of the effects suggests that an individualization of the stimulation frequency is necessary in heterogeneous target groups with a large variation in IAF.

Abstract

Visuospatial attention can either be voluntarily directed (endogenous/top-down attention) or automatically triggered (exogenous/bottom-up attention). Recent research showed that dorsal parietal transcranial alternating current stimulation (tACS) at alpha frequency modulates the spatial attentional bias in an endogenous but not in an exogenous visuospatial attention task. Yet, the reason for this task-specificity remains unexplored. Here, we tested whether this dissociation relates to the proposed differential role of the dorsal attention network (DAN) and ventral attention network (VAN) in endogenous and exogenous attention processes respectively. To that aim, we targeted the left and right dorsal parietal node of the DAN, as well as the left and right ventral temporoparietal node of the VAN using tACS at the individual alpha frequency. Every participant completed all four stimulation conditions and a sham condition in five separate sessions. During tACS, we assessed the behavioral visuospatial attention bias via an endogenous and exogenous visuospatial attention task. Additionally, we measured offline alpha power immediately before and after tACS using electroencephalography (EEG). The behavioral data revealed an effect of tACS on the endogenous but not exogenous attention bias, with a greater leftward bias during (sham-corrected) left than right hemispheric stimulation. In line with our hypothesis, this effect was brain area-specific, i.e., present for dorsal parietal but not ventral temporoparietal tACS. However, contrary to our expectations, there was no effect of ventral temporoparietal tACS on the exogenous visuospatial attention bias. Hence, no double dissociation between the two targeted attention networks. There was no effect of either tACS condition on offline alpha power. Our behavioral data reveal that dorsal parietal but not ventral temporoparietal alpha oscillations steer endogenous visuospatial attention. This brain-area specific tACS effect matches the previously proposed dissociation between the DAN and VAN and, by showing that the spatial attention bias effect does not generalize to any lateral posterior tACS montage, renders lateral cutaneous and retinal effects for the spatial attention bias in the dorsal parietal condition unlikely. Yet the absence of tACS effects on the exogenous attention task suggests that ventral temporoparietal alpha oscillations are not functionally relevant for exogenous visuospatial attention. We discuss the potential implications of this finding in the context of an emerging theory on the role of the ventral temporoparietal node.

Abstract

The psychological process of translating semantic into syntactic structures has dynamic properties such as the following. (1) The speaker is able to start pronouncing an utterance before having worked out the semantic content he wishes to express. Selection of semantic content and construction of syntactic form proceed partially in parallel. (2) The human sentence generator takes as input not only a specification of semantic content but also some indication of desired syntactic shape. Such indications, if present, do not complicate the generation process but make it easier. (3) Certain regularities of speech errors suggest a two-stage generation process. Stage I constructs the “syntactic skeleton” of an utterance; stage II provides the skeleton with morpho- honological information. An outline is given of the type of grammar which is used by a sentence generation system embodying these characteristics. The system is being implemented on a computer.

Abstract

When you compare the behavior of two different age groups which are trying to master the same sensori-motor or cognitive skill, you are likely to discover varying learning routes: different stages, different intervals between stages, or even different orderings of stages. Such heterogeneous learning trajectories may be caused by at least six different types of factors: (1) Initial state: the kinds and levels of skills the learners have available at the onset of the learning episode. (2) Learning mechanisms: rule-based, inductive, connectionist, parameter setting, and so on. (3) Input and feedback characteristics: learning stimuli, information about success and failure. (4) Information processing mechanisms: capacity limitations, attentional biases, response preferences. (5) Energetic variables: motivation, emotional reactions. (6) Final state: the fine-structure of kinds and levels of subskills at the end of the learning episode. This applies to language acquisition as well. First and second language learners probably differ on all six factors. Nevertheless, the debate between advocates and opponents of the Fundamental Difference Hypothesis concerning L1 and L2 acquisition have looked almost exclusively at the first two factors. Those who believe that L1 learners have access to Universal Grammar whereas L2 learners rely on language processing strategies, postulate different learning mechanisms (UG parameter setting in L1, more general inductive strategies in L2 learning). Pienemann opposes this view and, based on his Processability Theory, argues that L1 and L2 learners start out from different initial states: they come to the grammar learning task with different structural hypotheses (SOV versus SVO as basic word order of German).

Abstract

In a recent Cognition paper (Cognition 85 (2002) B21), Bornkessel, Schlesewsky, and Friederici report ERP data that they claim “show that online processing difficulties induced by word order variations in German cannot be attributed to the relative infrequency of the constructions in question, but rather appear to reflect the application of grammatical principles during parsing” (p. B21). In this commentary we demonstrate that the posited contrast between grammatical principles and construction (in)frequency as sources of parsing problems is artificial because it is based on factually incorrect assumptions about the grammar of German and on inaccurate corpus frequency data concerning the German constructions involved.

Abstract

Previous work has shown that Dutch listeners use prosodic information in the speech signal to optimise morphological processing: Listeners are sensitive to prosodic differences between a noun stem realised in isolation and a noun stem realised as part of a plural form (in which the stem is followed by an unstressed syllable). The present study, employing a lexical decision task, provides an additional demonstration of listeners' sensitivity to prosodic cues in the stem. This sensitivity is shown for two languages that differ in morphological productivity: Dutch and English. The degree of morphological productivity does not correlate with listeners' sensitivity to prosodic cues in the stem, but it is reflected in differential sensitivities to the word-specific log odds ratio of encountering an unshortened stem (i.e., a stem in isolation) versus encountering a shortened stem (i.e., a stem followed by a suffix consisting of one or more unstressed syllables). In addition to being sensitive to the prosodic cues themselves, listeners are also sensitive to the probabilities of occurrence of these prosodic cues.

Abstract

It has recently been shown that listeners use systematic differences in vowel length and intonation to resolve ambiguities between onset-matched simple words (Davis, Marslen-Wilson, & Gaskell, 2002; Salverda, Dahan, & McQueen, 2003). The present study shows that listeners also use prosodic information in the speech signal to optimize morphological processing. The precise acoustic realization of the stem provides crucial information to the listener about the morphological context in which the stem appears and attenuates the competition between stored inflectional variants. We argue that listeners are able to make use of prosodic information, even though the speech signal is highly variable within and between speakers, by virtue of the relative invariance of the duration of the onset. This provides listeners with a baseline against which the durational cues in a vowel and a coda can be evaluated. Furthermore, our experiments provide evidence for item-specific prosodic effects.

Abstract

In Dutch, high-frequency words with the suffix -lijk are often highly reduced in spontaneous unscripted speech. This study addressed socio-geographic variation in the reduction of such words against the backdrop of the variation in their use in written and spoken Dutch. Multivariate analyses of the frequencies with which the words were used in a factorially contrasted set of subcorpora revealed signi ficant variation involving the speaker's country, sex, and education level for spoken Dutch, and involving country and register for written Dutch. Acoustic analyses revealed that Dutch men reduced most often, while Flemish highly educated women reduced least. Two linguistic context effects emerged, one prosodic, and the other pertaining to the flow of information. Words in sentence final position showed less reduction, while words that were better predictable from the preceding word in the sentence(based on mutual information) tended to be reduced more often. The increased probability of reduction for forms that are more predictable in context, combined with the loss of the suffix in the more extremely reduced forms, suggests that highfrequency words in -lijk are undergoing a process of erosion that causes them to gravitate towards monomorphemic function words.

Abstract

A comprehensive theory of child language acquisition requires an evidential base that is representative of the typological diversity present in the world’s 7000 or so languages. However, languages are dying at an alarming rate, and the next 50 years represents the last chance we have to document acquisition in many of them. Here, we take stock of the last 45 years of research published in the four main child language acquisition journals: Journal of Child Language, First Language, Language Acquisition and Language Learning and Development. We coded each article for several variables, including (1) participant group (mono vs multilingual), (2) language(s), (3) topic(s) and (4) country of author affiliation, from each journal’s inception until the end of 2020. We found that we have at least one article published on around 103 languages, representing approximately 1.5% of the world’s languages. The distribution of articles was highly skewed towards English and other well-studied Indo-European languages, with the majority of non-Indo-European languages having just one paper. A majority of the papers focused on studies of monolingual children, although papers did not always explicitly report participant group status. The distribution of topics across language categories was more even. The number of articles published on non-Indo-European languages from countries outside of North America and Europe is increasing; however, this increase is driven by research conducted in relatively wealthy countries. Overall, the vast majority of the research was produced in the Global North. We conclude that, despite a proud history of crosslinguistic research, the goals of the discipline need to be recalibrated before we can lay claim to truly a representative account of child language acquisition.

Abstract

Our original target article highlighted some significant shortcomings in the current state of child language research: a large skew in our evidential base towards English and a handful of other Indo-European languages that partly has its origins in a lack of researcher diversity. In this article, we respond to the 21 commentaries on our original article. The commentaries highlighted both the importance of attention to typological features of languages and the environments and contexts in which languages are acquired, with many commentators providing concrete suggestions on how we address the data skew. In this response, we synthesise the main themes of the commentaries and make suggestions for how the field can move towards both improving data coverage and opening up to traditionally under-represented researchers.

Abstract

This paper reports on an investigation of children's (aged 3;5–9;8) comprehension of sentences containing ambiguity of prepositional phrase (PP) attachment. Results from a picture selection study (N=90) showed that children use verb semantics and preposition type to resolve the ambiguity, with older children also showing sensitivity to the definiteness of the object NP as a cue to interpretation. Study 2 investigated three- and five-year-old children's (N=47) ability to override an instrumental interpretation of ambiguous PPs in order to process attributes of the referential scene. The results showed that while five-year-olds are capable of incorporating aspects of the referential scene into their interpretations, three-year-olds are not as successful. Overall, the results suggest that children are attuned very early to the lexico-semantic co-occurrences that have been shown to aid ambiguity resolution in adults, but that more diffuse cues to interpretation are used only later in development

Abstract

Eisenberg (2002) presents data from an experiment investigating three- and four-year-old children's comprehension of restrictive relative clauses (RC). From the results she argues, contrary to Hamburger & Crain (1982), that children do not have discourse knowledge of the felicity conditions of RCs before acquiring the syntax of relativization. This note evaluates this conclusion on the basis of the methodology used, and proposes that an account of syntactic development needs to be sensitive to the real-time processing requirements acquisition places on the learner.

Abstract

Infant pointing has long been identified as an important precursor and predictor of language development. Infants typically begin to produce index finger pointing around the time of their first birthday and previous research has shown that both the onset and the frequency of pointing can predict aspects of productive and receptive language. The current study used a multivariate meta-analytic approach to estimate the strength of the relationship between infant pointing and language. We identified 30 papers published between 1984 and 2019 that met our stringent inclusion criteria, and 25 studies (comprising 77 effect sizes) with samples ≥10 were analysed. Methodological quality of the studies was assessed to identify potential sources of bias. We found a significant but small overall effect size of r = 0.20. Our findings indicate that the unique contribution of pointing to language development may be less robust than has been previously understood, however our stringent inclusion criteria (as well as our publication bias corrections), means that our data represent a more conservative estimate of the relationship between pointing and language. Moderator analysis showed significant group differences in favour of effect sizes related to language comprehension, non-vocabulary measures of language, pointing assessed after 18 months of age and pointing measured independent of speech. A significant strength of this study is the use of multivariate meta-analysis, which allowed us to utilise all available data to provide a more accurate estimate. We consider the findings in the context of the existing research and discuss the general limitations in this field, including the lack of cultural diversity.

Abstract

Gestures that spontaneously accompany speech convey information coordinated with the concurrent speech. There has been considerable theoretical disagreement about the process by which this informational coordination is achieved. Some theories predict that the information encoded in gesture is not influenced by how information is verbally expressed. However, others predict that gestures encode only what is encoded in speech. This paper investigates this issue by comparing informational coordination between speech and gesture across different languages. Narratives in Turkish, Japanese, and English were elicited using an animated cartoon as the stimulus. It was found that gestures used to express the same motion events were influenced simultaneously by (1) how features of motion events were expressed in each language, and (2) spatial information in the stimulus that was never verbalized. From this, it is concluded that gestures are generated from spatio-motoric processes that interact on-line with the speech production process. Through the interaction, spatio-motoric information to be expressed is packaged into chunks that are verbalizable within a processing unit for speech formulation. In addition, we propose a model of speech and gesture production as one of a class of frameworks that are compatible with the data.

Abstract

In the first, critical part of this study, a small sample of simple German sentences with their empirically determined pitch contours is used to demonstrate the incorrectness of numerous currently hold views of German sentence intonation. In the second, more constructive part, several interrogative sentence types are analysed and an attempt is made to show that intonation, besides other functions, indicates the permantently changing 'thematic score' in on-going discourse as well as certain validity claims.

Abstract

During the last 25 years, second language acquisition (SLA) research hasmade considerable progress, but is still far from proving a solid basis for foreign language teaching, or from a general theory of SLA. In addition, its status within the linguistic disciplines is still very low. I argue this has not much to do with low empirical or theoretical standards in the field—in this regard, SLA research is fully competitive—but with a particular perspective on the acquisition process: SLA researches learners' utterances as deviations from a certain target, instead of genuine manifestations of underlying language capacity; it analyses them in terms of what they are not rather than what they are. For some purposes such a "target deviation perspective" makes sense, but it will not help SLA researchers to substantially and independently contribute to a deeper understanding of the structure and function of the human language faculty. Therefore, these findings will remain of limited interest to other scientists until SLA researchers consider learner varieties a normal, in fact typical, manifestation of this unique human capacity.

Abstract

The problem of poor reproducibility of scientific findings has received much attention over recent years, in a variety of fields including psychology and neuroscience. The problem has been partly attributed to publication bias and unwanted practices such as p‐hacking. Low statistical power in individual studies is also understood to be an important factor. In a recent multisite collaborative study, we mapped brain anatomical left–right asymmetries for regional measures of surface area and cortical thickness, in 99 MRI datasets from around the world, for a total of over 17,000 participants. In the present study, we revisited these hemispheric effects from the perspective of reproducibility. Within each dataset, we considered that an effect had been reproduced when it matched the meta‐analytic effect from the 98 other datasets, in terms of effect direction and significance threshold. In this sense, the results within each dataset were viewed as coming from separate studies in an “ideal publishing environment,” that is, free from selective reporting and p hacking. We found an average reproducibility rate of 63.2% (SD = 22.9%, min = 22.2%, max = 97.0%). As expected, reproducibility was higher for larger effects and in larger datasets. Reproducibility was not obviously related to the age of participants, scanner field strength, FreeSurfer software version, cortical regional measurement reliability, or regional size. These findings constitute an empirical illustration of reproducibility in the absence of publication bias or p hacking, when assessing realistic biological effects in heterogeneous neuroscience data, and given typically‐used sample sizes.

Abstract

Left-right asymmetry of the human brain is one of its cardinal features, and also a complex, multivariate trait. Decades of research have suggested that brain asymmetry may be altered in psychiatric disorders. However, findings have been inconsistent and often based on small sample sizes. There are also open questions surrounding which structures are asymmetrical on average in the healthy population, and how variability in brain asymmetry relates to basic biological variables such as age and sex. Over the last four years, the ENIGMA-Laterality Working Group has published six studies of grey matter morphological asymmetry based on total sample sizes from roughly 3,500 to 17,000 individuals, which were between one and two orders of magnitude larger than those published in previous decades. A population-level mapping of average asymmetry was achieved, including an
intriguing fronto-occipital gradient of cortical thickness asymmetry in healthy brains. ENIGMA’s multidataset approach also supported an empirical illustration of reproducibility of hemispheric differences across datasets. Effect sizes were estimated for grey matter asymmetry based on large, international,
samples in relation to age, sex, handedness, and brain volume, as well as for three psychiatric disorders:Autism Spectrum Disorder was associated with subtly reduced asymmetry of cortical thickness at regions spread widely over the cortex; Pediatric Obsessive-Compulsive Disorder was associated with altered subcortical asymmetry; Major Depressive Disorder was not significantly associated with changes
of asymmetry. Ongoing studies are examining brain asymmetry in other disorders. Moreover, a groundwork has been laid for possibly identifying shared genetic contributions to brain asymmetry and disorders.

Abstract

Children begin to talk at about age one. The vocabulary they need to do so must be built on perceptual evidence and, indeed, infants begin to recognize spoken words long before they talk. Most of the utterances infants hear, however, are continuous, without pauses between words, so constructing a vocabulary requires them to decompose continuous speech in order to extract the individual words. Here, we present electrophysiological evidence that 10-month-old infants recognize two-syllable words they have previously heard only in isolation when these words are presented anew in continuous speech. Moreover, they only need roughly the first syllable of the word to begin doing this. Thus, prelinguistic infants command a highly efficient procedure for segmentation and recognition of spoken words in the absence of an existing vocabulary, allowing them to tackle effectively the problem of bootstrapping a lexicon out of the highly variable, continuous speech signals in their environment.

Abstract

In various applications of forensic phonetics the question arises as to how far aural-perceptual speaker recognition performance is reliable. Therefore, it is necessary to examine the relationship between speaker recognition results and human perception/production abilities like musicality or speech sensitivity. In this study, performance in a speaker recognition experiment and a speech sensitivity test are correlated. The results show a moderately significant positive correlation between the two tasks. Generally, performance in the speaker recognition task was better than in the speech sensitivity test. Professionals in speech and singing yielded a more homogeneous correlation than non-experts. Training in speech as well as choir-singing seems to have a positive effect on performance in speaker recognition. It may be concluded, firstly, that in cases where the reliability of voice line-up results or the credibility of a testimony have to be considered, the speech sensitivity test could be a useful indicator. Secondly, the speech sensitivity test might be integrated into the canon of possible procedures for the accreditation of forensic phoneticians. Both tests may also be used in combination.

Abstract

The article considers the pragmatics of silence image in English poetry. Silence being a communicative unit is
associated with verbal and non-verbal communication. The purpose of the article is to study the discursive and
communicative-pragmatic nature of poetical images of silence in the English-language literary discourse. The universal
and cultural functions of this notion were analysed and the main approaches to the poetical silence study were
determined. It became clear that the phenomenon of Nature Silence can be actualised with the help of Nature and other
landscape images in the field of English literary discourse. Such images must belong to the paradigm of English
landscape images represented by Earthy, Aerial and Celestial substantial nature symbols. In terms of
discourse-communicative approach to the study of communicative silence, these elements play an important role of the
main producers of Nature Silence. This work proposes the new pragmatic and communicative approach of
understanding the Nature silence in English literary discourse. The main verbal units that can actualise the poetical
image of silence are characterised by the permanent correlation with the different symbols of nature, showing the
dominant and peripheral characteristics. Being the pragmatic realisation of silence image, motives of Nature Silence
may be considered both as dominant and background.

Abstract

Theories of language acquisition vary significantly in their assumptions regarding the content of children’s early syntactic representations and how they subsequently develop towards the adult state. An important methodological tool in tapping syntactic knowledge is priming. In the current paper, we report the first longitudinal investigation of syntactic priming in children, to test the competing predictions of three different theoretical accounts. A sample of 106 children completed a syntactic priming task testing the English active/passive alternation every six months from 36 months to 54 months of age. We tracked both the emergence and development of the abstract priming effect and lexical boost effect. The lexical boost effect emerged late and increased in magnitude over development, whilst the abstract priming effect emerged early and, in a subsample of participants who produced at least one passive at 36 months, decreased in magnitude over time. In addition, there was substantial variation in the emergence of abstract priming amongst our sample, which was significantly predicted by language proficiency measured six months prior. We conclude that children’s representation of the passive is abstracted early, with lexically dependent priming coming online only later in development. The results are best explained by an implicit learning account of acquisition (Chang, F., Dell, G., S., & Bock, K. 2006. Becoming Syntactic. Psychological Review, 113, 234–272), which induces dynamic syntactic representations from the input that continue to change across developmental time.

Abstract

Disruption of FOXP2, a gene encoding a forkhead-domain transcription factor, causes a severe developmental disorder of verbal communication, involving profound articulation deficits, accompanied by linguistic and grammatical impairments. Investigation of the neural basis of this disorder has been limited previously to neuroimaging of affected children and adults. The discovery of the gene responsible, FOXP2, offers a unique opportunity to explore the relevant neural mechanisms from a molecular perspective. In the present study, we have determined the detailed spatial and temporal expression pattern of FOXP2 mRNA in the developing brain of mouse and human. We find expression in several structures including the cortical plate, basal ganglia, thalamus, inferior olives and cerebellum. These data support a role for FOXP2 in the development of corticostriatal and olivocerebellar circuits involved in motor control. We find intriguing concordance between regions of early expression and later sites of pathology suggested by neuroimaging. Moreover, the homologous pattern of FOXP2/Foxp2 expression in human and mouse argues for a role for this gene in development of motor-related circuits throughout mammalian species. Overall, this study provides support for the hypothesis that impairments in sequencing of movement and procedural learning might be central to the FOXP2-related speech and language disorder.

Abstract

Introduction: Mood is a constant in our daily life and can permeate all levels of cognition. We examined whether and how mood influences the processing of discourse content that is relatively neutral and not loaded with emotion. During discourse processing, readers have to constantly strike a balance between what they know in long term memory and what the current discourse is about. Our general hypothesis is that mood states would affect this balance. We hypothesized that readers in a positive mood would rely more on default world knowledge, whereas readers in a negative mood would be more inclined to analyze the details in the current discourse.

Methods: Participants were put in a positive and a negative mood via film clips, one week apart. In each session, after mood manipulation, they were presented with sentences in discourse materials. We created sentences such as “With the lights on you can see...” that end with critical words (CWs) “more” or “less”, where general knowledge supports “more”, not “less”. We then embedded each of these sentences in a wider discourse that does/does not support the CWs (a story about driving in the night vs. stargazing). EEG was recorded throughout.

Results: The results showed that first, mood manipulation was successful in that there was a significant mood difference between sessions. Second, mood did not modulate the N400 effects. Participants in both moods detected outright semantic violations and allowed world knowledge to be overridden by discourse context. Third, mood modulated the LPC (Late Positive Component) effects, distributed in the frontal region. In negative moods, the LPC was sensitive to one-level violation. That is, CWs that were supported by only world knowledge, only discourse, and neither, elicited larger frontal LPCs, in comparison to the condition where CWs were supported by both world knowledge and discourse.

Discussion: These results suggest that mood does not influence all processes involved in discourse processing. Specifically, mood does not influence lexical-semantic retrieval (N400), but it does influence elaborative processes for sensemaking (P600) during discourse processing. These results advance our understanding of the impact and time course of mood on discourse.

Abstract

The chronic fatigue syndrome (CFS) is a disabling disorder of unknown etiology. The symptomatology of CFS (central fatigue, impaired concentration, attention and memory) suggests that this disorder could be related to alterations at the level of the central nervous system. In this study, we have used an automated and unbiased morphometric technique to test whether CFS patients display structural cerebral abnormalities. We mapped structural cerebral morphology and volume in two cohorts of CFS patients (in total 28 patients) and healthy controls (in total 28 controls) from high-resolution structural magnetic resonance images, using voxel-based morphometry. Additionally, we recorded physical activity levels to explore the relation between severity of CFS symptoms and cerebral abnormalities. We observed significant reductions in global gray matter volume in both cohorts of CFS patients, as compared to matched control participants. Moreover, the decline in gray matter volume was linked to the reduction in physical activity, a core aspect of CFS. These findings suggest that the central nervous system plays a key role in the pathophysiology of CFS and point to a new objective and quantitative tool for clinical diagnosis of this disabling disorder.

Abstract

We have used implicit motor imagery to investigate the neural correlates of motor planning independently from actual movements. Subjects were presented with drawings of left or right hands and asked to judge the hand laterality, regardless of the stimulus rotation from its upright orientation. We paired this task with a visual imagery control task, in which subjects were presented with typographical characters and asked to report whether they saw a canonical letter or its mirror image, regardless of its rotation. We measured neurovascular activity with fast event-related fMRI, distinguishing responses parametrically related to motor imagery from responses evoked by visual imagery and other task-related phenomena. By quantifying behavioral and neurovascular correlates of imagery on a trial-by-trial basis, we could discriminate between stimulusrelated, mental rotation-related, and response-related neural activity. We found that specific portions of the posterior parietal and precentral cortex increased their activity as a function of mental rotation only during the motor imagery task. Within these regions, the parietal cortex was visually responsive, whereas the dorsal precentral cortex was not. Response- but not rotation-related activity was found around the left central sulcus (putative primary motor cortex) during both imagery tasks. Our study provides novel evidence on the topography and content of movement representations in the human brain. During intended action, the posterior parietal cortex combines somatosensory and visuomotor information, whereas the dorsal premotor cortex generates the actual motor plan, and the primary motor cortex deals with movement execution. We discuss the relevance of these results in the context of current models of action planning.

Abstract

Executive functioning (EF) plays a major role in many domains of human behaviour, including self-regulation, academic achievement, and even sports expertise. While a significant proportion of cross-sectional research has focused on the developmental pathways of EF, the existing literature is fractionated due to a wide range of methodologies applied to narrow age ranges, impeding comparison across a broad range of age groups. The current study used a cross-sectional design to investigate the factor structure of EF within late childhood and adolescence. A total of 2166 Flemish children and adolescents completed seven tasks of the Cambridge Brain Sciences test battery. Based on the existing literature, a Confirmatory Factor Analysis was performed, which indicated that a unitary factor model provides the best fit for the youngest age group (7–12 years). For the adolescents (12–18 years), the factor structure consists of four different components, including working memory, shifting, inhibition and planning. With regard to differences between early (12–15 years) and late (15–18 years) adolescents, working memory, inhibition and planning show higher scores for the late adolescents, while there was no difference on shifting. The current study is one of the first to administer the same seven EF tests in a considerably large sample of children and adolescents, and as such contributes to the understanding of the developmental trends in EF. Future studies, especially with longitudinal designs, are encouraged to further increase the knowledge concerning the factor structure of EF, and the development of the different EF components.

Abstract

Investigations of left hand praxis in imitation and object use in patients with callosal disconnection have yielded divergent results, inducing a debate between two theoretical positions. Whereas Liepmann suggested that the left hemisphere is motor dominant, others maintain that both hemispheres have equal motor competences and propose that left hand apraxia in patients with callosal disconnection is secondary to left hemispheric specialization for language or other task modalities. The present study aims to gain further insight into the motor competence of the right hemisphere by investigating pantomime of object use in split-brain patients. Three patients with complete callosotomy and, as control groups, five patients with partial callosotomy and nine healthy subjects were examined for their ability to pantomime object use to visual object presentation and demonstrate object manipulation. In each condition, 11 objects were presented to the subjects who pantomimed or demonstrated the object use with either hand. In addition, six object pairs were presented to test bimanual coordination. Two independent raters evaluated the videotaped movement demonstrations. While object use demonstrations were perfect in all three groups, the split-brain patients displayed apraxic errors only with their left hands in the pantomime condition. The movement analysis of concept and execution errors included the examination of ipsilateral versus contralateral motor control. As the right hand/left hemisphere performances demonstrated retrieval of the correct movement concepts, concept errors by the left hand were taken as evidence for right hemisphere control. Several types of execution errors reflected a lack of distal motor control indicating the use of ipsilateral pathways. While one split-brain patient controlled his left hand predominantly by ipsilateral pathways in the pantomime condition, the error profile in the other two split-brain patients suggested that the right hemisphere controlled their left hands. In the object use condition, in all three split-brain patients fine-graded distal movements in the left hand indicated right hemispheric control. Our data show left hand apraxia in split-brain patients is not limited to verbal commands, but also occurs in pantomime to visual presentation of objects. As the demonstration with object in hand was unimpaired in either hand, both hemispheres must contain movement concepts for object use. However, the disconnected right hemisphere is impaired in retrieving the movement concept in response to visual object presentation, presumably because of a deficit in associating perceptual object representation with the movement concepts.

Abstract

Since some patients with right hemisphere damage or with spontaneous callosal disconnection neglect the left half of space, it has been suggested that the left cerebral hemisphere predominantly attends to the right half of space. However, clinical investigations of patients having undergone surgical callosal section have not shown neglect when the hemispheres are tested separately. These observations question the validity of theoretical models that propose a left hemispheric specialisation for attending to the right half of space. The present study aims to investigate neglect and the use of space by either hand in gestural demonstrations in three split-brain patients as compared to five patients with partial callosotomy and 11 healthy subjects. Subjects were asked to demonstrate with precise gestures and without speaking the content of animated scenes with two moving objects. The results show that in the absence of primary perceptual or representational neglect, split-brain patients neglect left personal space in right-handed gestural demonstrations. Since this neglect of left personal space cannot be explained by directional or spatial akinesia, it is suggested that it originates at the conceptual level, where the spatial coordinates for right-hand gestures are planned. The present findings are at odds with the position that the separate left hemisphere possesses adequate mechanisms for acting in both halves of space and neglect results from right hemisphere suppression of this potential. Rather, the results provide support for theoretical models that consider the left hemisphere as specialised for processing the right half of space during the execution of descriptive gestures.

Abstract

The present study investigates the hand choice in iconic gestures that accompany speech. In 10 right-handed subjects gestures were elicited by verbal narration and by silent gestural demonstrations of animations with two moving objects. In both conditions, the left-hand was used as often as the right-hand to display iconic gestures. The choice of the right- or left-hands was determined by semantic aspects of the message. The influence of hemispheric language lateralization on the hand choice in co-speech gestures appeared to be minor. Instead, speaking seemed to induce a sequential organization of the iconic gestures.

Abstract

Using real-time eye-movement measures, we asked how a fantastical discourse context competes with stored representations of real-world events to influence the moment-by-moment interpretation of a story by 7-year-old children and adults. Seven-year-olds were less effective at bypassing stored real-world knowledge during real-time interpretation than adults. Our results suggest that children privilege stored semantic knowledge over situation-specific information presented in a fictional story context. We suggest that 7-year-olds’ canonical semantic and conceptual relations are sufficiently strongly rooted in statistical patterns in language that have consolidated over time that they overwhelm new and unexpected information even when the latter is fantastical and highly salient.

Abstract

The way we process language is influenced by our experience. We are more likely to attend to features that proved to be useful in the past. Importantly, the size of individuals’ social network can influence their experience, and consequently, how they process language. In the case of voice recognition, having a larger social network might provide more variable input and thus enhance the ability to recognise new voices. On the other hand, learning to recognise voices is more demanding and less beneficial for people with a larger social network as they have more speakers to learn yet spend less time with each. This paper tests whether social network size influences voice recognition, and if so, in which direction. Native Dutch speakers listed their social network and performed a voice recognition task. Results showed that people with larger social networks were poorer at learning to recognise voices. Experiment 2 replicated the results with a British sample and English stimuli. Experiment 3 showed that the effect does not generalise to voice recognition in an unfamiliar language suggesting that social network size influences attention to the linguistic rather than non-linguistic markers that differentiate speakers. The studies thus show that our social network size influences our inclination to learn speaker-specific patterns in our environment, and consequently, the development of skills that rely on such learned patterns, such as voice recognition.

Abstract

The purpose of this study was to relate a psycholinguistic processing model of picture naming to the dynamics of cortical activation during picture naming. The activation was recorded from eight Dutch subjects with a whole-head neuromagnetometer. The processing model, based on extensive naming latency studies, is a stage model. In preparing a picture's name, the speaker performs a chain of specific operations. They are, in this order, computing the visual percept, activating an appropriate lexical concept, selecting the target word from the mental lexicon, phonological encoding, phonetic encoding, and initiation of articulation. The time windows for each of these operations are reasonably well known and could be related to the peak activity of dipole sources in the individual magnetic response patterns. The analyses showed a clear progression over these time windows from early occipital activation, via parietal and temporal to frontal activation. The major specific findings were that (1) a region in the left posterior temporal lobe, agreeing with the location of Wernicke's area, showed prominent activation starting about 200 msec after picture onset and peaking at about 350 msec, (i.e., within the stage of phonological encoding), and (2) a consistent activation was found in the right parietal cortex, peaking at about 230 msec after picture onset, thus preceding and partly overlapping with the left temporal response. An interpretation in terms of the management of visual attention is proposed.

Abstract

The topic of this paper is the way in which speakers order information in discourse. I will refer to this issue with the term "linearization", and will begin with two types of general remarks. The first one concerns the scope and relevance of the problem with reference to some existing literature. The second set of general remarks will be about the place of linearization in a theory of the speaker. The following, and main part of this paper, will be a summary report of research of linearization in a limited, but well-defined domain of discourse, namely the description of spatial networks.

Abstract

This commentary discusses whether abstract metrical frames are stored. For stress-assigning languages (e.g., Dutch and English), which have a dominant stress pattern, metrical frames are stored only for words that deviate from the default stress pattern. The majority of the words in these languages are produced without retrieving any independent syllabic or metrical frame.

Abstract

In their comment, Dell and O'Seaghdha (1991) adduced any effect on phonological probes for semantic alternatives to the activation of these probes in the lexical network. We argue that that interpretation is false and, in addition, that the model still cannot account for our data. Furthermore, and different from Dell and O'seaghda, we adduce semantic rebound to the lemma level, where it is so substantial that it should have shown up in our data. Finally, we question the function of feedback in a lexical network (other than eliciting speech errors) and discuss Dell's (1988) notion of a unified production-comprehension system.

Abstract

Speakers tend to repeat materials from previous talk. This tendency is experimentally established and manipulated in various question-answering situations. It is shown that a question's surface form can affect the format of the answer given, even if this form has little semantic or conversational consequence, as in the pair Q: (At) what time do you close. A: “(At)five o'clock.” Answerers tend to match the utterance to the prepositional (nonprepositional) form of the question. This “correspondence effect” may diminish or disappear when, following the question, additional verbal material is presented to the answerer. The experiments show that neither the articulatory buffer nor long-term memory is normally involved in this retention of recent speech. Retaining recent speech in working memory may fulfill a variety of functions for speaker and listener, among them the correct production and interpretation of surface anaphora. Reusing recent materials may, moreover, be more economical than regenerating speech anew from a semantic base, and thus contribute to fluency. But the realization of this strategy requires a production system in which linguistic formulation can take place relatively independent of, and parallel to, conceptual planning.

Abstract

The core issue in the 19-century sources of psycholinguistics was the question, "Where does language come from?'' This genetic perspective unified the study of the ontogenesis, the phylogenesis, the microgenesis, and to some extent the neurogenesis of language. This paper makes the point that this original perspective is still a valid and attractive one. It is exemplified by a discussion of the genesis of spoken words.