Publications

Abstract

We examine representations of time among the Mianmin of Papua New Guinea. We begin by describing the patterns of spatial and temporal reference in Mian. Mian uses a system of spatial terms that derive from the orientation and direction of the Hak and Sek rivers and the surrounding landscape. We then report results from a temporal arrangement task administered to a group of Mian speakers. The results reveal evidence for a variety of temporal representations. Some participants arranged time with respect to their bodies (left to right or toward the body). Others arranged time as laid out on the landscape, roughly along the east/west axis (either east to west or west to east). This absolute pattern is consistent both with the axis of the motion of the sun and the orientation of the two rivers, which provides the basis for spatial reference in the Mian language. The results also suggest an increase in left-to-right temporal representations with increasing years of formal education (and the reverse pattern for absolute spatial representations for time). These results extend previous work on spatial representations for time to a new geographical region, physical environment, and linguistic and cultural system.

Abstract

The brain has the extraordinary capacity to construct predictive models of the environment by internalizing statistical regularities in the sensory inputs. The resulting sensory expectations shape how we perceive and react to the world; at the neural level, this relates to decreased neural responses to expected than unexpected stimuli (‘expectation suppression’). Crucially, expectations may need revision as context changes. However, existing research has often neglected this issue. Further, it is unclear whether contextual revisions apply selectively to expectations relevant to the task at hand, hence serving adaptive behaviour. The present fMRI study examined how contextual visual expectations spread throughout the cortical hierarchy as participants update their beliefs. We created a volatile environment with two state spaces presented over separate contexts and controlled by an independent contextualizing signal. Participants attended a training session before scanning to learn contextual temporal associations among pairs of object images. The fMRI experiment then tested for the emergence of contextual expectation suppression in two separate tasks, respectively with task-relevant and task-irrelevant expectations. Behavioural and neural effects of contextual expectation emerged progressively across the cortical hierarchy as participants attuned themselves to the context: expectation suppression appeared first in the insula, inferior frontal gyrus and posterior parietal cortex, followed by the ventral visual stream, up to early visual cortex. This applied selectively to task-relevant expectations. Taken together, the present results suggest that an insular and frontoparietal executive control network may guide the flexible deployment of contextual sensory expectations for adaptive behaviour in our complex and dynamic world.

Abstract

The constituents of attractiveness differ across the sexes. Many relevant traits are dimorphic, suggesting that they are the product of intersexual selection. However, direction of causality is generally difficult to determine, as aesthetic criteria can as readily result from, as cause, dimorphism. Women have proportionately smaller feet than men. Prior work on the role of foot size in attractiveness suggests an asymmetry across the sexes, as small feet enhance female appearance, yet average, rather than large, feet are preferred on men. Previous investigations employed crude stimuli and limited samples. Here, we report on multiple cross-cultural studies designed to overcome these limitations. With the exception of one rural society, we find that small foot size is preferred when judging women, yet no equivalent preference applies to men. Similarly, consonant with the thesis that a preference for youth underlies intersexual selection acting on women, we document an inverse relationship between foot size and perceived age. Examination of preferences regarding, and inferences from, feet viewed in isolation suggests different roles for proportionality and absolute size in judgments of female and male bodies. Although the majority of these results bolster the conclusion that pedal dimorphism is the product of intersexual selection, the picture is complicated by the reversal of the usual preference for small female feet found in one rural society. While possibly explicable in terms of greater emphasis on female economic productivity relative to beauty, the latter finding underscores the importance of employing diverse samples when exploring postulated evolved aesthetic preferences.

Abstract

The evolutionary origins of music are much debated. One theory holds that the ability to produce complex musical sounds might reflect qualities that are relevant in mate choice contexts and hence, that music is functionally analogous to the sexually-selected acoustic displays of some animals. If so, women may be expected to show heightened preferences for more complex music when they are most fertile. Here, we used computer-generated musical pieces and ovulation predictor kits to test this hypothesis. Our results indicate that women prefer more complex music in general; however, we found no evidence that their preference for more complex music increased around ovulation. Consequently, our findings are not consistent with the hypothesis that a heightened preference/bias in women for more complex music around ovulation could have played a role in the evolution of music. We go on to suggest future studies that could further investigate whether sexual selection played a role in the evolution of this universal aspect of human culture.

Abstract

Developmental disorders affecting speech and language are highly heritable, but very little is currently understood about the neuromolecular mechanisms that underlie these traits. Integration of data from diverse research areas, including linguistics, neuropsychology, neuroimaging, genetics, molecular neuroscience, developmental biology, and evolutionary anthropology, is becoming essential for unraveling the relevant pathways. Recent studies of the FOXP2 gene provide a case in point. Mutation of FOXP2 causes a rare form of speech and language disorder, and the gene appears to be a crucial regulator of embryonic development for several tissues. Molecular investigations of the central nervous system indicate that the gene may be involved in establishing and maintaining connectivity of corticostriatal and olivocerebellar circuits in mammals. Notably, it has been shown that FOXP2 was subject to positive selection in recent human evolution. Consideration of findings from multiple levels of analysis demonstrates that FOXP2 cannot be characterized as “the gene for speech,” but rather as one critical piece of a complex puzzle. This story gives a flavor of what is to come in this field and indicates that anyone expecting simple explanations of etiology or evolution should be prepared for some intriguing surprises.

Abstract

Learning to talk is one of the most important milestones in human development, but we still have only a limited understanding of the way in which the process occurs. It normally takes just a few years to go from babbling newborn to fluent communicator. During this period, the child learns to produce a rich array of speech sounds through intricate control of articulatory muscles, assembles a vocabulary comprising thousands of words, and deduces the complicated structural rules that permit construction of meaningful sentences. All of this (and more) is achieved with little conscious effort.

Abstract

The human Xp11.23-p11.22 interval has been implicated in several inherited diseases including Wiskott-Aldrich syndrome; three forms of X-linked hypercalciuric nephrolithiaisis; and the eye disorders retinitis pigmentosa 2, congenital stationary night blindness, and Aland Island eye disease. In constructing YAC contigs spanning Xp11. 23-p11.22, we have previously shown that the region around the synaptophysin (SYP) gene is refractory to cloning in YACs, but highly stable in cosmids. Preliminary analysis of the latter suggested that this might reflect a high density of coding sequences and we therefore undertook the complete sequencing of a SYP-containing cosmid. Sequence data were extensively analyzed using computer programs such as CENSOR (to mask repeats), BLAST (for homology searches), and GRAIL and GENE-ID (to predict exons). This revealed the presence of 29 putative exons, organized into three genes, in addition to the 7 exons of the complete SYP coding region, all mapping within a 44-kb interval. Two genes are novel, one (CACNA1F) showing high homology to alpha1 subunits of calcium channels, the other (LMO6) encoding a product with significant similarity to LIM-domain proteins. RT-PCR and Northern blot studies confirmed that these loci are indeed transcribed. The third locus is the previously described, but not previously localized, A4 differentiation-dependent gene. Given that the intron-exon boundaries predicted by the analysis are consistent with previous information where available, we have been able to suggest the genomic organization of the novel genes with some confidence. The region has an elevated GC content (>53%), and we identified CpG islands associated with the 5' ends of SYP, A4, and LMO6. The order of loci was Xpter-A4-LMO6-SYP-CACNA1F-Xcen, with intergenic distances ranging from approximately 300 bp to approximately 5 kb. The density of transcribed sequences in this area (>80%) is comparable to that found in the highly gene-rich chromosomal band Xq28. Further studies may aid our understanding of the long-range organization surrounding such gene-enriched regions.

Abstract

Research on pattern perception and rule learning, grounded in formal language theory (FLT) and using artificial grammar learning paradigms, has exploded in the last decade. This approach marries empirical research conducted by neuroscientists, psychologists and ethologists with the theory of computation and FLT, developed by mathematicians, linguists and computer scientists over the last century. Of particular current interest are comparative extensions of this work to non-human animals, and neuroscientific investigations using brain imaging techniques. We provide a short introduction to the history of these fields, and to some of the dominant hypotheses, to help contextualize these ongoing research programmes, and finally briefly introduce the papers in the current issue.

Abstract

No abstract is available for this article

Abstract

Understanding the progression of neurological diseases is vital for accurate and early diagnosis and treatment planning. We introduce a new characterization of disease progression, which describes the disease as a series of events, each comprising a significant change in patient state. We provide novel algorithms to learn the event ordering from heterogeneous measurements over a whole patient cohort and demonstrate using combined imaging and clinical data from familial-Alzheimer's and Huntington's disease cohorts. Results provide new detail in the progression pattern of these diseases, while confirming known features, and give unique insight into the variability of progression over the cohort. The key advantage of the new model and algorithms over previous progression models is that they do not require a priori division of the patients into clinical stages. The model and its formulation extend naturally to a wide range of other diseases and developmental processes and accommodate cross-sectional and longitudinal input data.

Abstract

Cognitive functional neuroimaging has been around for over 30 years and has shed light on the brain areas relevant for reading. However, new methodological developments enable mapping the interaction between functional imaging and the underlying white matter networks. In this study, we used such a novel method, called the disconnectome, to decode the reading circuitry in the brain. We used the resulting disconnection patterns to predict a typical lesion that would lead to reading deficits after brain damage. Our results suggest that white matter connections critical for reading include fronto-parietal U-shaped fibres and the vertical occipital fasciculus (VOF). The lesion most predictive of a reading deficit would impinge on the left temporal, occipital, and inferior parietal gyri. This novel framework can systematically be applied to bridge the gap between the neuropathology of language and cognitive neuroscience.

Abstract

Inter-individual differences can inform treatment procedures and—if accounted for—have the potential to significantly improve patient outcomes. However, when studying brain anatomy, these inter-individual variations are commonly unaccounted for, despite reports of differences in gross anatomical features, cross-sectional, and connectional anatomy. Brain connections are essential to facilitate functional organization and, when severed, cause impairments or complete loss of function. Hence, the study of cerebral white matter may be an ideal compromise to capture inter-individual variability in structure and function. We reviewed the wealth of studies that associate cognitive functions and clinical symptoms with individual tracts using diffusion tractography. Our systematic review indicates that tractography has proven to be a sensitive method in neurology, psychiatry, and healthy populations to identify variability and its functional correlates. However, the literature may be biased, as the most commonly studied tracts are not necessarily those with the highest sensitivity to cognitive functions and pathologies. Additionally, the hemisphere of the studied tract is often unreported, thus neglecting functional laterality and asymmetries. Finally, we demonstrate that tracts, as we define them, are not correlated with one, but multiple cognitive domains or pathologies. While our systematic review identified some methodological caveats, it also suggests that tract–function correlations might still be a promising tool in identifying biomarkers for precision medicine. They can characterize variations in brain anatomy, differences in functional organization, and predicts resilience and recovery in patients.

Abstract

Purpose of review: The human brain supports acquisition mechanisms that can extract structural regularities implicitly from experience without the induction of an explicit model. Reber defined the process by which an individual comes to respond appropriately to the statistical structure of the input ensemble as implicit learning. He argued that the capacity to generalize to new input is based on the acquisition of abstract representations that reflect underlying structural regularities in the acquisition input. We focus this review of the implicit learning literature on studies published during 2004 and 2005. We will not review studies of repetition priming ('implicit memory'). Instead we focus on two commonly used experimental paradigms: the serial reaction time task and artificial grammar learning. Previous comprehensive reviews can be found in Seger's 1994 article and the Handbook of Implicit Learning. Recent findings: Emerging themes include the interaction between implicit and explicit processes, the role of the medial temporal lobe, developmental aspects of implicit learning, age-dependence, the role of sleep and consolidation. Summary: The attempts to characterize the interaction between implicit and explicit learning are promising although not well understood. The same can be said about the role of sleep and consolidation. Despite the fact that lesion studies have relatively consistently suggested that the medial temporal lobe memory system is not necessary for implicit learning, a number of functional magnetic resonance studies have reported medial temporal lobe activation in implicit learning. This issue merits further research. Finally, the clinical relevance of implicit learning remains to be determined.

Abstract

Progress in genome sequencing now enables the large-scale generation of reference genomes. Various international initiatives aim to generate reference genomes representing global biodiversity. These genomes provide unique insights into genomic diversity and architecture, thereby enabling comprehensive analyses of population and functional genomics, and are expected to revolutionize conservation genomics.

Abstract

The cognate effect refers to translation equivalents with similar form between languages—i.e., cognates, such as “band” (English) and “banda” (Spanish)—being processed faster than words with dissimilar forms—such as, “cloud” and “nube.” Substantive literature supports this claim, but is mostly based on orthographic similarity and tested in the visual modality. In a previous study, we found an inhibitory orthographic similarity effect in the auditory modality—i.e., greater orthographic similarity led to slower response times and reduced accuracy. The aim of the present study is to explain this effect. In doing so, we explore the role of the speaker's accent in auditory word recognition and whether native accents lead to a mismatch between the participants' phonological representation and the stimulus. Participants carried out a lexical decision task and a typing task in which they spelled out the word they heard. Words were produced by two speakers: one with a native English accent (Standard American) and the other with a non-native accent matching that of the participants (native Spanish speaker from Spain). We manipulated orthographic and phonological similarity orthogonally and found that accent did have some effect on both response time and accuracy as well as modulating the effects of similarity. Overall, the non-native accent improved performance, but it did not fully explain why high orthographic similarity items show an inhibitory effect in the auditory modality. Theoretical implications and future directions are discussed.

Abstract

Delineating the association of age and cortical thickness in healthy individuals is critical given the association of cortical thickness with cognition and behavior. Previous research has shown that robust estimates of the association between age and brain morphometry require large‐scale studies. In response, we used cross‐sectional data from 17,075 individuals aged 3–90 years from the Enhancing Neuroimaging Genetics through Meta‐Analysis (ENIGMA) Consortium to infer age‐related changes in cortical thickness. We used fractional polynomial (FP) regression to quantify the association between age and cortical thickness, and we computed normalized growth centiles using the parametric Lambda, Mu, and Sigma method. Interindividual variability was estimated using meta‐analysis and one‐way analysis of variance. For most regions, their highest cortical thickness value was observed in childhood. Age and cortical thickness showed a negative association; the slope was steeper up to the third decade of life and more gradual thereafter; notable exceptions to this general pattern were entorhinal, temporopolar, and anterior cingulate cortices. Interindividual variability was largest in temporal and frontal regions across the lifespan. Age and its FP combinations explained up to 59% variance in cortical thickness. These results may form the basis of further investigation on normative deviation in cortical thickness and its significance for behavioral and cognitive outcomes.

Abstract

A spelling disorder that received much attention recently is the so-called graphemic buffer impairment. Caramazza et al. (1987) presented the first systematic case study of a patient with this disorder. Miceli & Capasso (2006) provide an extensive overview of the relevant literature. This article adds to the literature by describing a Dutch case, i.e. patient BM. We demonstrate how specific features of Dutch and Dutch orthography interact with the graphemic buffer impairment. In addition, we paid special attention to the influence of grapheme position on the patient’s spelling accuracy. For this we used, in contrast with most of the previous literature, the proportional accountability method described in Machtynger & Shallice (2009). We show that by using this method the underlying error distribution can be more optimally captured than with classical methods. The result of this analysis replicates two distributions that have been previously reported in the literature. Finally, attention will be paid to the role of phonology in the described disorder.

Abstract

Mutations in the human FOXP2 gene cause impaired speech development and linguistic deficits, which have been best characterised in a large pedigree called the KE family. The encoded protein is highly conserved in many vertebrates and is expressed in homologous brain regions required for sensorimotor integration and motor-skill learning, in particular corticostriatal circuits. Independent studies in multiple species suggest that the striatum is a key site of FOXP2 action. Here, we used in vivo recordings in awake-behaving mice to investigate the effects of the KE-family mutation on the function of striatal circuits during motor-skill learning. We uncovered abnormally high ongoing striatal activity in mice carrying an identical mutation to that of the KE family. Furthermore, there were dramatic alterations in striatal plasticity during the acquisition of a motor skill, with most neurons in mutants showing negative modulation of firing rate, starkly contrasting with the predominantly positive modulation seen in control animals. We also observed striking changes in the temporal coordination of striatal firing during motor-skill learning in mutants. Our results indicate that FOXP2 is critical for the function of striatal circuits in vivo, which are important not only for speech but also for other striatal-dependent skills.

Abstract

The current study investigates whether self-talk phrases can influence behavior in Ultimatum Games. In our three self-talk treatments, participants were instructed to tell themselves (i) to keep their own interests in mind, (ii) to also think of the other person, or (iii) to take some time to contemplate their decision. We investigate how such so-called experimenter-determined strategic self-talk phrases affect behavior and emotions in comparison to a control treatment without instructed self-talk. The results demonstrate that other-focused self-talk can nudge proposers towards fair behavior, as offers were higher in this group than in the other conditions. For responders, self-talk tended to increase acceptance rates of unfair offers as compared to the condition without self-talk. This effect is significant for both other-focused and contemplation-inducing self-talk but not for self-focused self-talk. In the self-focused condition, responders were most dissatisfied with unfair offers. These findings suggest that use of self-talk can increase acceptance rates in responders, and that focusing on personal interests can undermine this effect as it negatively impacts the responders’ emotional experience. In sum, our study shows that strategic self-talk interventions can be used to affect behavior in bargaining situations.

Abstract

Sleep plays an important role in neural reorganisation which underpins memory consolidation. The gradual replacement of
hippocampal binding of new memories with intracortical connections helps to link new memories to existing knowledge. This process appears to be faster for memories which fit more easily into existing schemas. Here we seek to investigate whether this more rapid consolidation of schema-conformant information is facilitated by
sleep, and the neural basis of this process.

Abstract

Since the discovery that rhythmic abilities are universal in humans, temporal features of vocal communication have greatly interested researchers studying animal communication. Rhythmic patterns are a valuable tool for species discrimination, mate choice, and individual recognition. A recent study showed that bird songs and human music share rhythmic categories when a signal's temporal intervals are distributed categorically rather than uniformly. Following that study, we aimed to investigate whether songs of indris (Indri indri), the only singing lemur, may show similar features. We measured the inter-onset intervals (tk), delimited by the onsets of two consecutive units, and the rhythmic ratios between these intervals (rk), calculated by dividing an interval by itself plus its adjacent, and finded a three-cluster distribution. Two clusters corresponded to rhythmic categories at 1:1 and 1:2, and the third approached a 2:1 ratio. Our results demonstrated for the first time that another primate besides humans produces categorical rhythms, an ability likely evolved convergently among singing species such as songbirds, indris, and humans. Understanding which communicative features are shared with other species is fundamental to understanding how they have evolved. In this regard, thanks to the simplicity of data processing and interpretation, our study relied on an accessible analytical approach that could open up new branches of the investigation into primate communication, leading the way to reconstruct a phylogeny of rhythm abilities across the entire order.

Abstract

Many contemporary texts include shortcuts, such as cu or phones4u. The aim of this study was to investigate how the meanings of shortcuts are retrieved. A primed lexical decision paradigm was used with shortcuts and the corresponding words as primes. The target word was associatively related to the meaning of the whole prime (cu/see you – goodbye), to a component of the prime (cu/see you – look), or unrelated to the prime. In Experiment 1, primes were presented for 57 ms. For both word and shortcut primes, responses were faster to targets preceded by whole-related than by unrelated primes. No priming from component-related primes was found. In Experiment 2, the prime duration was 1000 ms. The priming effect seen in Experiment 1 was replicated. Additionally, there was priming from component-related word primes, but not from component-related shortcut primes. These results indicate that the meanings of shortcuts can be retrieved without translating them first into corresponding words.

Abstract

Whether reading in different writing systems recruits language-unique or language-universal neural processes is a long-standing debate. Many studies have shown the left arcuate fasciculus (AF) to be involved in phonological and reading processes. In contrast, little is known about the role of the right AF in reading, but some have suggested that it may play a role in visual spatial aspects of reading or the prosodic components of language. The right AF may be more important for reading in Chinese due to its logographic and tonal properties, but this hypothesis has yet to be tested. We recruited a group of Chinese-English bilingual children (8.2 to 12.0 years old) to explore the common and unique relation of reading skill in English and Chinese to fractional anisotropy (FA) in the bilateral AF. We found that both English and Chinese reading skills were positively correlated with FA in the rostral part of the left AF-direct segment. Additionally, English reading skill was positively correlated with FA in the caudal part of the left AF-direct segment, which was also positively correlated with phonological awareness. In contrast, Chinese reading skill was positively correlated with FA in certain segments of the right AF, which was positively correlated with visual spatial ability, but not tone discrimination ability. Our results suggest that there are language universal substrates of reading across languages, but that certain left AF nodes support phonological mechanisms important for reading in English, whereas certain right AF nodes support visual spatial mechanisms important for reading in Chinese.

Abstract

The effortfulness hypothesis implies that difficulty in decoding the surface form, as in the case of age-related sensory limitations or background noise, consumes the attentional resources that are then unavailable for semantic integration in language comprehension. Because ageing is associated with sensory declines, degrading of the surface form by a noisy background can pose an extra challenge for older adults. In two experiments, this hypothesis was tested in a self-paced moving window paradigm in which younger and older readers' online allocation of attentional resources to surface decoding and semantic integration was measured as they read sentences embedded in varying levels of visual noise. When visual noise was moderate (Experiment 1), resource allocation among young adults was unaffected but older adults allocated more resources to decode the surface form at the cost of resources that would otherwise be available for semantic processing; when visual noise was relatively intense (Experiment 2), both younger and older participants allocated more attention to the surface form and less attention to semantic processing. The decrease in attentional allocation to semantic integration resulted in reduced recall of core ideas in both experiments, suggesting that a less organized semantic representation was constructed in noise. The greater vulnerability of older adults at relatively low levels of noise is consistent with the effortfulness hypothesis.

Abstract

The COVID-19 pandemic has massively limited how linguists can collect data, and out of necessity, researchers across several disciplines have moved data collection online. Here we argue that the rising popularity of remote web-based experiments also provides an opportunity for widening the context of linguistic research by facilitating data collection from understudied populations. We discuss collecting production data from adult native speakers of Tagalog using an unsupervised web-based experiment. Compared to equivalent lab experiments, data collection went quicker, and the sample was more diverse, without compromising data quality. However, there were also technical and human issues that come with this method. We discuss these challenges and provide suggestions on how to overcome them.

Abstract

Western Austronesian languages have typologically rare but theoretically important voice systems that raise many questions about their learnability. While these languages have been featured prominently in the descriptive and typological literature, data on acquisition is sparse. In the current paper, we report on a variationist analysis of Tagalog child-directed speech using a newly collected corpus of caregiver-child interaction. We determined the constraints that condition voice use, voice selection, argument position, and thematic role assignment, thus providing the first quantitative analysis of verb argument structure variation in the language. We also examined whether children are sensitive to the constraints on variability. Our analyses showed that, despite the diversity of structures that children have to learn under Tagalog’s voice system, there are unique factors that strongly predict the speakers’ choice between the voice and word order alternations, with children’s choices related to structure alternations being similar to what is available in their input. The results thus suggest that input distributions provide many cues to the acquisition of the Tagalog voice system, making it eminently learnable despite its apparent complexity.

Abstract

Meta-analyses provide researchers with an overview of the body of evidence in a topic, with quantified estimates of effect sizes and the role of moderators, and weighting studies according to their precision. We provide a guide for conducting a transparent and reproducible meta-analysis in the field of developmental psychology within the framework of the MetaLab platform, in 10 steps: (1) Choose a topic for your meta-analysis, (2) Formulate your research question and specify inclusion criteria, (3) Preregister and document all stages of your meta-analysis, (4) Conduct the literature search, (5) Collect and screen records, (6) Extract data from eligible studies, (7) Read the data into analysis software and compute effect sizes, (8) Visualize your data, (9) Create meta-analytic models to assess the strength of the effect and investigate possible moderators, (10) Write up and promote your meta-analysis. Meta-analyses can inform future studies, through power calculations, by identifying robust methods and exposing research gaps. By adding a new meta-analysis to MetaLab, datasets across multiple topics of developmental psychology can be synthesized, and the dataset can be maintained as a living, community-augmented meta-analysis to which researchers add new data, allowing for a cumulative approach to evidence synthesis.

Abstract

BACKGROUND: There is a growing interest in the study of the genetic origins of comorbidity, a direct consequence of the recent findings of genetic loci that are seemingly linked to more than one disorder. There are several potential causes for these shared regions of linkage, but one possibility is that these loci may harbor genes with manifold effects. The established genetic correlation between reading disability (RD) and attention-deficit/hyperactivity disorder (ADHD) suggests that their comorbidity is due at least in part to genes that have an impact on several phenotypes, a phenomenon known as pleiotropy. METHODS: We employ a bivariate linkage test for selected samples that could help identify these pleiotropic loci. This linkage method was employed to carry out the first bivariate genome-wide analysis for RD and ADHD, in a selected sample of 182 sibling pairs. RESULTS: We found evidence for a novel locus at chromosome 14q32 (multipoint LOD=2.5; singlepoint LOD=3.9) with a pleiotropic effect on RD and ADHD. Another locus at 13q32, which had been implicated in previous univariate scans of RD and ADHD, seems to have a pleiotropic effect on both disorders. 20q11 is also suggested as a pleiotropic locus. Other loci previously implicated in RD or ADHD did not exhibit bivariate linkage. CONCLUSIONS: Some loci are suggested as having pleiotropic effects on RD and ADHD, while others might have unique effects. These results highlight the utility of this bivariate linkage method to study pleiotropy.

Abstract

Understanding human white matter development is vital to characterize typical brain organization and developmental neurocognitive disorders. In this issue of Neuron, Nazeri and colleagues1 identify different parts of white matter in the neonatal brain and show their maturational trajectories in line with microstructural feature development.

Abstract

In principle mutational records make it possible to estimate frequencies of disease alleles (q) for autosomal recessive disorders using a novel approach based on the calculation of the Homozygosity Index (HI), i.e., the proportion of homozygous patients, which is complementary to the proportion of compound heterozygous patients P(CH). In other words, the rarer the disorder, the higher will be the HI and the lower will be the P(CH). To test this hypothesis we used mutational records of individuals affected with Familial Mediterranean Fever (FMF) and Phenylketonuria (PKU), born to either consanguineous or apparently unrelated parents from six population samples of the Mediterranean region. Despite the unavailability of precise values of the inbreeding coefficient for the general population, which are needed in the case of apparently unrelated parents, our estimates of q are very similar to those of previous descriptive epidemiological studies. Finally, we inferred from simulation studies that the minimum sample size needed to use this approach is 25 patients either with unrelated or first cousin parents. These results show that the HI can be used to produce a ranking order of allele frequencies of autosomal recessive disorders, especially in populations with high rates of consanguineous marriages.

Abstract

The neurobiology of sentence production has been largely understudied compared to the neurobiology of sentence comprehension, due to difficulties with experimental control and motion-related artifacts in neuroimaging. We studied the neural response to constituents of increasing size and specifically focused on the similarities and differences in the production and comprehension of the same stimuli. Participants had to either produce or listen to stimuli in a gradient of constituent size based on a visual prompt. Larger constituent sizes engaged the left inferior frontal gyrus (LIFG) and middle temporal gyrus (LMTG) extending to inferior parietal areas in both production and comprehension, confirming that the neural resources for syntactic encoding and decoding are largely overlapping. An ROI analysis in LIFG and LMTG also showed that production elicited larger responses to constituent size than comprehension and that the LMTG was more engaged in comprehension than production, while the LIFG was more engaged in production than comprehension. Finally, increasing constituent size was characterized by later BOLD peaks in comprehension but earlier peaks in production. These results show that syntactic encoding and parsing engage overlapping areas, but there are asymmetries in the engagement of the language network due to the specific requirements of production and comprehension.

Abstract

Gender stereotypes have endured despite substantial change in gender roles. Previous work has assessed how gender stereotypes affect language production in particular interactional contexts. Here, we assessed communication biases where context was less specified: written texts to diffuse audiences. We used Latent Semantic Analysis (LSA) to computationally quantify the similarity in meaning between gendered names and stereotype-linked terms in these communications. This revealed that female names were more similar in meaning to the proscriptive (undesirable) masculine terms, such as emotional.

Abstract

Purpose: Aphasia fluency is multiply determined by underlying impairments in lexical retrieval, grammatical formulation, and speech production. This poses challenges for establishing a reliable and feasible tool to measure fluency in the clinic. We examine the reliability and validity of perceptual ratings and clinical perspectives on the utility and relevance of methods used to assess fluency.
Method: In an online survey, 112 speech-language pathologists rated spontaneous speech samples from 181 people with aphasia (PwA) on eight perceptual rating scales (overall fluency, speech rate, pausing, effort, melody, phrase length, grammaticality, and lexical retrieval) and answered questions about their current practices for assessing fluency in the clinic.
Results: Interrater reliability for the eight perceptual rating scales ranged from fair to good. The most reliable scales were speech rate, pausing, and phrase length. Similarly, clinicians' perceived fluency ratings were most strongly correlated to objective measures of speech rate and utterance length but were also related to grammatical complexity, lexical diversity, and phonological errors. Clinicians' ratings reflected expected aphasia subtype patterns: Individuals with Broca's and transcortical motor aphasia were rated below average on fluency, whereas those with anomic, conduction, and Wernicke's aphasia were rated above average. Most respondents reported using multiple methods in the clinic to measure fluency but relying most frequently on subjective judgments.
Conclusions: This study lends support for the use of perceptual rating scales as valid assessments of speech-language production but highlights the need for a more reliable method for clinical use. We describe next steps for developing such a tool that is clinically feasible and helps to identify the underlying deficits disrupting fluency to inform treatment targets.

Abstract

Adopting the paradigm of a study conducted with chimpanzees, Pan troglodytes (Melis et al. 2006, Journal of Comparative Psychology, 120, 154–162), we investigated orang-utans', Pongo pygmaeus, understanding of others' visual perspectives. More specifically, we examined whether orang-utans would adjust their behaviour in a way that prevents a human competitor from seeing them steal a piece of food. In the task, subjects had to reach through one of two opposing Plexiglas tunnels in order to retrieve a food reward. Both rewards were also physically accessible to a human competitor sitting opposite the subject. Subjects always had the possibility of reaching one piece of food that was outside the human's line of sight. This was because either the human was oriented to one, but not the other, reward or because one tunnel was covered by an opaque barrier and the other remained transparent. In the situation in which the human was oriented towards one reward, the orang-utans successfully avoided the tunnel that the competitor was facing. If one tunnel was covered, they marginally preferred to reach through the opaque versus the transparent tunnel. However, they did so frequently after initially inspecting the transparent tunnel (then switching to the opaque one). Considering only the subjects' initial inspections, they chose randomly between the opaque and transparent tunnel, indicating that their final decision to reach was probably driven by a more egocentric behavioural rule. Overall the results suggest that orang-utans have a limited understanding of others' perspectives, relying mainly on cues from facial and bodily orientation and egocentric rules when making such judgements.

Abstract

Most people have a right-ear advantage for the perception of spoken syllables, consistent with left hemisphere dominance for speech processing. However, there is considerable variation, with some people showing left-ear advantage. The extent to which this variation is reflected in brain structure remains unclear. We tested for relations between hemispheric asymmetries of auditory processing and of grey matter in 281 adults, using dichotic listening and voxel-based morphometry. This was the largest study of this issue to date. Per-voxel asymmetry indexes were derived for each participant following registration of brain magnetic resonance images to a template that was symmetrized. The asymmetry index derived from dichotic listening was related to grey matter asymmetry in clusters of voxels corresponding to the amygdala and cerebellum lobule VI. There was also a smaller, non-significant cluster in the posterior superior temporal gyrus, a region of auditory cortex. These findings contribute to the mapping of asymmetrical structure–function links in the human brain and suggest that subcortical structures should be investigated in relation to hemispheric dominance for speech processing, in addition to auditory cortex.

Abstract

PURPOSE: Time spent in "sports/outdoor activity" has shown a negative association with incident myopia during childhood. We investigated the association of incident myopia with time spent outdoors and physical activity separately. METHODS: Participants in the Avon Longitudinal Study of Parents and Children (ALSPAC) were assessed by noncycloplegic autorefraction at ages 7, 10, 11, 12, and 15 years, and classified as myopic (≤-1 diopters) or as emmetropic/hyperopic (≥-0.25 diopters) at each visit (N = 4,837-7,747). Physical activity at age 11 years was measured objectively using an accelerometer, worn for 1 week. Time spent outdoors was assessed via a parental questionnaire administered when children were aged 8-9 years. Variables associated with incident myopia were examined using Cox regression. RESULTS: In analyses using all available data, both time spent outdoors and physical activity were associated with incident myopia, with time outdoors having the larger effect. The results were similar for analyses restricted to children classified as either nonmyopic or emmetropic/hyperopic at age 11 years. Thus, for children nonmyopic at age 11, the hazard ratio (95% confidence interval, CI) for incident myopia was 0.66 (0.47-0.93) for a high versus low amount of time spent outdoors, and 0.87 (0.76-0.99) per unit standard deviation above average increase in moderate/vigorous physical activity. CONCLUSION: Time spent outdoors was predictive of incident myopia independently of physical activity level. The greater association observed for time outdoors suggests that the previously reported link between "sports/outdoor activity" and incident myopia is due mainly to its capture of information relating to time outdoors rather than physical activity.

Abstract

Discussions about the adult L2 learning capacity often take as their starting point stages where considerable L2 knowledge has already been accumulated. This paper probes the absolute earliest stages of learning and investigates what lexical knowledge adult learners can extract from complex, continuous speech in an unknown language after minimal exposure and without any help. Dutch participants were exposed to naturalistic but controlled audiovisual input in Mandarin Chinese, in which item frequency and gestural highlighting were manipulated. The results from a word recognition task showed that adults are able to draw on frequency to recognize disyllabic words appearing only eight times in continuous speech. The findings from a sound-to-picture matching task revealed that the mapping of meaning to word form requires a combination of cues: disyllabic words accompanied by a gesture were correctly assigned meaning after eight encounters. Overall, the study suggests that the adult learning mechanism is a considerably more powerful than typically assumed in the SLA literature drawing on frequency, gestural cues and syllable structure. Even in the absence of pre-existing knowledge about cognates and sound system to bootstrap and boost learning, it deals efficiently with very little, very complex input.

Abstract

The present study investigates the effects of late sign language exposure on narrative development in Turkish Sign Language (TİD) by focusing on the introductions of main characters and the linguistic strategies used in these introductions. We study these domains by comparing narrations produced by native and late signers in TİD. The results of our study reveal that late sign language exposure does not hinder the acquisition of linguistic devices to introduce main characters in narrations. Thus, their acquisition seems to be resilient to the effects of late language exposure. Our study further suggests that a two-year exposure to sign language facilitates the acquisition of these skills in signing children even in the case of late language exposure, thus providing further support for the importance of sign language exposure to develop linguistic skills for signing children.

Abstract

Many perception and processing effects of the lexical status of tone have been found in behavioral, psycholinguistic, and neuroscientific research, often pitting varieties of tonal Chinese against non-tonal Germanic languages. While the linguistic and cognitive evidence for lexical tone is therefore beyond dispute, the word prosodic systems of many languages continue to escape the categorizations of typologists. One controversy concerns the existence of a typological class of “pitch accent languages,” another the underlying phonological nature of surface tone contrasts, which in some cases have been claimed to be metrical rather than tonal. We address the question whether the Sequence Recall Task (SRT), which has been shown to discriminate between languages with and without word stress, can distinguish languages with and without lexical tone. Using participants from non-tonal Indonesian, semi-tonal Swedish, and two varieties of tonal Mandarin, we ran SRTs with monosyllabic tonal contrasts to test the hypothesis that high performance in a tonal SRT indicates the lexical status of tone. An additional question concerned the extent to which accuracy scores depended on phonological and phonetic properties of a language’s tone system, like its complexity, the existence of an experimental contrast in a language’s phonology, and the phonetic salience of a contrast. The results suggest that a tonal SRT is not likely to discriminate between tonal and non-tonal languages within a typologically varied group, because of the effects of specific properties of their tone systems. Future research should therefore address the first hypothesis with participants from otherwise similar tonal and non-tonal varieties of the same language, where results from a tonal SRT may make a useful contribution to the typological debate on word prosody.

Abstract

Previous research has set out to quantify the syntactic capacity of BERTje (the Dutch equivalent of BERT) in the context of phenomena such as control verb nesting and verb raising in Dutch. Another complex language phenomenon is ellipsis, where a constituent is omitted from a sentence and can be recovered using context. Like verb raising and control verb nesting, ellipsis is suitable for evaluating BERTje’s linguistic capacity since it requires the processing of syntactic and lexical cues to recover the elided phrases. This work outlines an approach to identify subject-verb dependencies in Dutch sentences with verb phrase and noun phrase ellipsis using BERTje. Results will inform about BERTje’s capability of capturing syntactic information and its ability to capture ellipsis in particular. Understanding more about how computational models process ellipsis and how it can be improved is crucial for boosting the performance of language models, as natural language contains many instances of ellipsis. Using training data from Lassy, converted to contextualized embeddings using BERTje, a probe model is trained to identify subject-verb dependencies. The model is tested on sentences generated using a Context Free Grammar (CFG), which is designed to generate sentences containing ellipsis. These sentences are also converted to contextualized representations using BERTje. Results show that BERTje’s syntactic abilities are lacking, shown by accuracy drops compared to baseline measures.

Abstract

“The most profound technologies are those that disappear. They weave themselves into the fabric of everyday life until they are indistinguishable from it.” (Weiser 1991, S. 94). – Die Behauptung stammt aus einem vielzitierten Text von Mark Weiser, ehemals Chief Technology Officer am berühmten Xerox Palo Alto Research Center (PARC), wo nicht nur einige bedeutende computertechnische Innovationen ihren Ursprung hatten, sondern auch grundlegende anthropologische Einsichten zum Umgang mit technischen Artefakten gewonnen wurden.1 In einem populärwissenschaftlichen Artikel mit dem Titel „The Computer for the 21st Century” entwarf Weiser 1991 die Vision einer Zukunft, in der wir nicht mehr mit einem einzelnen PC an unserem Arbeitsplatz umgehen – vielmehr seien wir in jedem Raum umgeben von hunderten elektronischer Vorrichtungen, die untrennbar in Alltagsgegenstände eingebettet und daher in unserer materiellen Umwelt gleichsam „verschwunden“ sind. Dabei ging es Weiser nicht allein um das ubiquitäre Phänomen, das in der Medientheorie als „Transparenz der Medien“ bekannt ist2 oder in allgemeineren Theorien der Alltagserfahrung als eine selbstverständliche Verwobenheit des Menschen mit den Dingen, die uns in ihrem Sinn vertraut und praktisch „zuhanden“ sind.3 Darüber hinaus zielte Weisers Vision darauf, unsere bereits existierende Umwelt durch computerlesbare Daten zu erweitern und in die Operationen eines solchen allgegenwärtigen Netzwerks alltägliche Praktiken gleichsam lückenlos zu integrieren: In der Welt, die Weiser entwirft, öffnen sich Türen für denjenigen, der ein bestimmtes elektronisches Abzeichen trägt, begrüßen Räume Personen, die sie betreten, mit Namen, passen sich Computerterminals an die Präferenzen individueller Nutzer an usw. (Weiser 1991, S. 99).

Abstract

“The most profound technologies are those that disappear. They weave themselves into the fabric of everyday life until they are indistinguishable from it.” (Weiser 1991, S. 94). – Die Behauptung stammt aus einem vielzitierten Text von Mark Weiser, ehemals Chief Technology Officer am berühmten Xerox Palo Alto Research Center (PARC), wo nicht nur einige bedeutende computertechnische Innovationen ihren Ursprung hatten, sondern auch grundlegende anthropologische Einsichten zum Umgang mit technischen Artefakten gewonnen wurden.1 In einem populärwissenschaftlichen Artikel mit dem Titel „The Computer for the 21st Century” entwarf Weiser 1991 die Vision einer Zukunft, in der wir nicht mehr mit einem einzelnen PC an unserem Arbeitsplatz umgehen – vielmehr seien wir in jedem Raum umgeben von hunderten elektronischer Vorrichtungen, die untrennbar in Alltagsgegenstände eingebettet und daher in unserer materiellen Umwelt gleichsam „verschwunden“ sind. Dabei ging es Weiser nicht allein um das ubiquitäre Phänomen, das in der Medientheorie als „Transparenz der Medien“ bekannt ist2 oder in allgemeineren Theorien der Alltagserfahrung als eine selbstverständliche Verwobenheit des Menschen mit den Dingen, die uns in ihrem Sinn vertraut und praktisch „zuhanden“ sind.3 Darüber hinaus zielte Weisers Vision darauf, unsere bereits existierende Umwelt durch computerlesbare Daten zu erweitern und in die Operationen eines solchen allgegenwärtigen Netzwerks alltägliche Praktiken gleichsam lückenlos zu integrieren: In der Welt, die Weiser entwirft, öffnen sich Türen für denjenigen, der ein bestimmtes elektronisches Abzeichen trägt, begrüßen Räume Personen, die sie betreten, mit Namen, passen sich Computerterminals an die Präferenzen individueller Nutzer an usw. (Weiser 1991, S. 99).

Abstract

In speaking and comprehending language, word information is retrieved from memory and combined into larger units (unification). Unification operations take place in parallel at the semantic, syntactic and phonological levels of processing. This article proposes a new framework that connects psycholinguistic models to a neurobiological account of language. According to this proposal the left inferior frontal gyrus (LIFG) plays an important role in unification. Research in other domains of cognition indicates that left prefrontal cortex has the necessary neurobiological characteristics for its involvement in the unification for language. I offer here a psycholinguistic perspective on the nature of language unification and the role of LIFG.

Abstract

Geen andere soort dan homo sapiens heeft in de loop van zijn evolutionaire geschiedenis een communicatiesysteem ontwikkeld waarin een eindig aantal symbolen samen met een reeks van regels voor het combineren daarvan een oneindig aantal uitdrukkingen mogelijk maakt. Dit natuurlijke taalsysteem stelt leden van onze soort in staat gedachten een uiterlijke vorm te geven en uit te wisselen met de sociale groep en, door de uitvinding van schriftsystemen, met de gehele samenleving. Spraak en taal zijn effectieve middelen voor het behoud van sociale cohesie in samenlevingen waarvan de groepsgrootte en de complexe sociale organisatie van dien aard is dat dit niet langer kan door middel van ‘vlooien’, de wijze waarop onze genetische buren, de primaten van de oude wereld, sociale cohesie bevorderen [1,2].

Abstract

This study tests the recent claim that Broca’s aphasics are impaired in automatic lexical access, including the retrieval of word meaning. Subjects are required to perform a lexical decision on visually presented prime target pairs. Half of the word targets are preceded by a related word, half by an unrelated word. Primes and targets are presented with a long stimulus-onset-asynchrony (SOA) of 1400 msec and with a short SOA of 300 msec. Normal priming effects are observed in Broca’s aphasics for both SOAs. This result is discussed in the context of the claim that Broca’s aphasics suffer from an impairment in the automatic access of lexical–semantic information. It is argued that none of the current priming studies provides evidence supporting this claim, since with short SOAs priming effects have been reliably obtained in Broca’s aphasics. The results are more compatible with the claim that in many Broca’s aphasics the functional locus of their comprehension deficit is at the level of postlexical integration processes.

Abstract

A series of articles by Ross (1995, 2001, 2005) use pronoun sim- ilarities to gauge relatedness between various Papuan microgroups, arguing that the similarities could not be the result of chance or bor- rowing. I argue that a more appropriate manner of calculating chance gives a signicantly dierent result: when cross-comparing a pool of languages the prospects for chance matches of rst and second person pronouns are very good. Using pronoun form data from over 3000 lan- guages and over 300 language families inside and outside New Guinea, I show that there is, nevertheless, a tendency for Papuan pronouns to use certain consonants more often in 1P and 2P SG forms than in the rest of the world. This could reect an underlying family. An alter- native explanation is the established Papuan areal feature of having a small consonant inventory, which results in a higher functional load on the remaining consonants, which is, in turn, reected in the enhanced popularity of certain consonants in pronouns of those languages. A test of surface forms (i.e., non-reconstructed forms) favours the latter explanation.

Abstract

This paper examines the role of morphological structure in the reduced pronunciation of morphologically complex words by discussing and re-analyzing data from the literature. Acoustic reduction refers to the phenomenon that, in spontaneous speech, phonemes may be shorter or absent. We review studies investigating effects of the repetition of a morpheme, of whether a segment plays a crucial role in the identification of its morpheme, and of a word's morphological decomposability. We conclude that these studies report either no effects of morphological structure or effects that are open to alternative interpretations. Our analysis also reveals the need for a uniform definition of morphological decomposability. Furthermore, we examine whether the reduction of segments in morphologically complex words correlates with these segments' contribution to the identification of the whole word, and discuss previous studies and new analyses supporting this hypothesis. We conclude that the data show no convincing evidence that morphological structure conditions reduction, which contrasts with the expectations of several models of speech production and of morphological processing (e.g., weaver++ and dual-route models). The data collected so far support psycholinguistic models which assume that all morphologically complex words are processed as complete units.

Abstract

Many learners of a foreign language (L2) struggle to correctly pronounce newly-learned speech sounds, yet many others achieve this with apparent ease. Here we explored how a training study of learning complex consonant clusters at the very onset of the L2 acquisition can inform us about L2 learning in general and individual differences in particular. To this end, adult Dutch native speakers were trained on Slovak words with complex consonant clusters (e.g., pstruh /pstrux/‘trout’, štvrť /ʃtvrc/ ‘quarter’) using auditory and orthographic input. In the same session following training, participants were tested on a battery of L2 perception and production tasks. The battery of L2 tests was repeated twice more with one week between each session. In the first session, an additional battery of control tests was used to test participants’ native language (L1) skills. Overall, in line with some previous research, participants showed only weak learning effects across the L2 perception tasks. However, there were considerable individual differences across all L2 tasks, which remained stable across sessions. Only two participants showed overall high L2 production performance that fell within 2 standard deviations of the mean ratings obtained for an L1 speaker. The mispronunciation detection task was the only perception task which significantly predicted production performance in the final session. We conclude by discussing several recommendations for future L2 learning studies.

Abstract

We used eyetracking, perceptual discrimination, and production tasks to examine the influences of perceptual similarity and linguistic experience on word recognition in nonnative (L2) speech. Eye movements to printed words were tracked while German and Dutch learners of English heard words containing one of three pronunciation variants (/t/, /s/, or /f/) of the interdental fricative /θ/. Irrespective of whether the speaker was Dutch or German, looking preferences for target words with /θ/ matched the preferences for producing /s/ variants in German speakers and /t/ variants in Dutch speakers (as determined via the production task), while a control group of English participants showed no such preferences. The perceptually most similar and most confusable /f/ variant (as determined via the discrimination task) was never preferred as a match for /θ/. These results suggest that linguistic experience with L2 pronunciations facilitates recognition of variants in an L2, with effects of frequency outweighing effects of perceptual similarity.

Abstract

How do native listeners process grammatical errors that are frequent in non-native speech? We investigated whether the neural correlates of syntactic processing are modulated by speaker identity. ERPs to gender agreement errors in sentences spoken by a native speaker were compared with the same errors spoken by a non-native speaker. In line with previous research, gender violations in native speech resulted in a P600 effect (larger P600 for violations in comparison with correct sentences), but when the same violations were produced by the non-native speaker with a foreign accent, no P600 effect was observed. Control sentences with semantic violations elicited comparable N400 effects for both the native and the non-native speaker, confirming no general integration problem in foreign-accented speech. The results demonstrate that the P600 is modulated by speaker identity, extending our knowledge about the role of speaker's characteristics on neural correlates of speech processing.

Abstract

CONTEXT Recent studies have shown an association between cigarettes per day (CPD) and a nonsynonymous single-nucleotide polymorphism in CHRNA5, rs16969968. OBJECTIVE To determine whether the association between rs16969968 and smoking is modified by age at onset of regular smoking. DATA SOURCES Primary data. STUDY SELECTION Available genetic studies containing measures of CPD and the genotype of rs16969968 or its proxy. DATA EXTRACTION Uniform statistical analysis scripts were run locally. Starting with 94 050 ever-smokers from 43 studies, we extracted the heavy smokers (CPD >20) and light smokers (CPD ≤10) with age-at-onset information, reducing the sample size to 33 348. Each study was stratified into early-onset smokers (age at onset ≤16 years) and late-onset smokers (age at onset >16 years), and a logistic regression of heavy vs light smoking with the rs16969968 genotype was computed for each stratum. Meta-analysis was performed within each age-at-onset stratum. DATA SYNTHESIS Individuals with 1 risk allele at rs16969968 who were early-onset smokers were significantly more likely to be heavy smokers in adulthood (odds ratio [OR] = 1.45; 95% CI, 1.36-1.55; n = 13 843) than were carriers of the risk allele who were late-onset smokers (OR = 1.27; 95% CI, 1.21-1.33, n = 19 505) (P = .01). CONCLUSION These results highlight an increased genetic vulnerability to smoking in early-onset smokers.

Abstract

Cultural transmission is a key component of human evolution. Two of humans' closest living relatives, chimpanzees and orangutans, have also been argued to transmit behavioral traditions across generations culturally [ [1], [2] and [3]], but how much the process might resemble the human process is still in large part unknown. One key phenomenon of human cultural transmission is majority-biased transmission: the increased likelihood for learners to end up not with the most frequent behavior but rather with the behavior demonstrated by most individuals. Here we show that chimpanzees and human children as young as 2 years of age, but not orangutans, are more likely to copy an action performed by three individuals, once each, than an action performed by one individual three times. The tendency to acquire the behaviors of the majority has been posited as key to the transmission of relatively safe, reliable, and productive behavioral strategies [ [4], [5], [6] and [7]] but has not previously been demonstrated in primates.

Abstract

Morphology is the study of the internal structure of words. A vigorous ongoing debate surrounds the question of how such internal structure is best accounted for: by means of lexical entries and deterministic symbolic rules, or by means of probabilistic subsymbolic networks implicitly encoding structural similarities in connection weights. In this review, we separate the question of subsymbolic versus symbolic implementation from the question of deterministic versus probabilistic structure. We outline a growing body of evidence, mostly external to the above debate, indicating that morphological structure is indeed intrinsically graded. By allowing probability into the grammar, progress can be made towards solving some long-standing puzzles in morphological theory.

Abstract

Human joint action is inherently cooperative, manifested in the collaborative efforts of participants to minimize communicative trouble through interactive repair. Although interactive repair requires sophisticated cognitive abilities,
it can be dissected into basic building blocks shared with non-human animal species. A review of the primate literature shows that interactionally contingent signal sequences are at least common among species of nonhuman great apes, suggesting a gradual evolution of repair. To pioneer a cross-species assessment of repair this paper aims at (i) identifying necessary precursors of human interactive repair; (ii) proposing a coding framework for its comparative study in humans and non-human species; and (iii) using this framework to analyse examples of interactions of humans (adults/children) and non-human great apes. We hope this paper will serve as a primer for cross-species comparisons of communicative breakdowns and how they are repaired.

Abstract

Understanding spoken language requires transforming ambiguous acoustic streams into a hierarchy of representations, from phonemes to meaning. It has been suggested that the brain uses prediction to guide the interpretation of incoming input. However, the role of prediction in language processing remains disputed, with disagreement about both the ubiquity and representational nature of predictions. Here, we address both issues by analyzing brain recordings of participants listening to audiobooks, and using a deep neural network (GPT-2) to precisely quantify contextual predictions. First, we establish that brain responses to words are modulated by ubiquitous predictions. Next, we disentangle model-based predictions into distinct dimensions, revealing dissociable neural signatures of predictions about syntactic category (parts of speech), phonemes, and semantics. Finally, we show that high-level (word) predictions inform low-level (phoneme) predictions, supporting hierarchical predictive processing. Together, these results underscore the ubiquity of prediction in language processing, showing that the brain spontaneously predicts upcoming language at multiple levels of abstraction.

Abstract

Culture, a pillar of the remarkable ecological success of humans, is increasingly recognized as a powerful force structuring nonhuman animal populations. A key gap between these two types of culture is quantitative evidence of symbolic markers—seemingly arbitrary traits that function as reliable indicators of cultural group membership to conspecifics. Using acoustic data collected from 23 Pacific Ocean locations, we provide quantitative evidence that certain sperm whale acoustic signals exhibit spatial patterns consistent with a symbolic marker function. Culture segments sperm whale populations into behaviorally distinct clans, which are defined based on dialects of stereotyped click patterns (codas). We classified 23,429 codas into types using contaminated mixture models and hierarchically clustered coda repertoires into seven clans based on similarities in coda usage; then we evaluated whether coda usage varied with geographic distance within clans or with spatial overlap between clans. Similarities in within-clan usage of both “identity codas” (coda types diagnostic of clan identity) and “nonidentity codas” (coda types used by multiple clans) decrease as space between repertoire recording locations increases. However, between-clan similarity in identity, but not nonidentity, coda usage decreases as clan spatial overlap increases. This matches expectations if sympatry is related to a measurable pressure to diversify to make cultural divisions sharper, thereby providing evidence that identity codas function as symbolic markers of clan identity. Our study provides quantitative evidence of arbitrary traits, resembling human ethnic markers, conveying cultural identity outside of humans, and highlights remarkable similarities in the distributions of human ethnolinguistic groups and sperm whale clans.

Abstract

Previous research suggests that literacy, specifically learning alphabetic letter-to-phoneme mappings, modifies online speech processing, and enhances brain responses, as indexed by the blood-oxygenation level dependent signal (BOLD), to speech in auditory areas associated with phonological processing (Dehaene et al., 2010). However, alphabets are not the only orthographic systems in use in the world, and hundreds of millions of individuals speak languages that are not written using alphabets. In order to make claims that literacy per se has broad and general consequences for brain responses to speech, one must seek confirmatory evidence from non-alphabetic literacy. To this end, we conducted a longitudinal fMRI study in India probing the effect of literacy in Devanagari, an abugida, on functional connectivity and cerebral responses to speech in 91 variously literate Hindi-speaking male and female human participants. Twenty-two completely illiterate participants underwent six months of reading and writing training. Devanagari literacy increases functional connectivity between acoustic-phonetic and graphomotor brain areas, but we find no evidence that literacy changes brain responses to speech, either in cross-sectional or longitudinal analyses. These findings shows that a dramatic reconfiguration of the neurofunctional substrates of online speech processing may not be a universal result of learning to read, and suggest that the influence of writing on speech processing should also be investigated.

Abstract

We used functional magnetic resonance imaging (fMRI) to investigate the neural basis of comprehension and perceptual learning of artificially degraded [noise vocoded (NV)] speech. Fifteen participants were scanned while listening to 6-channel vocoded words, which are difficult for naive listeners to comprehend, but can be readily learned with appropriate feedback presentations. During three test blocks, we compared responses to potentially intelligible NV words, incomprehensible distorted words and clear speech. Training sessions were interleaved with the test sessions and included paired presentation of clear then noise-vocoded words: a type of feedback that enhances perceptual learning. Listeners' comprehension of NV words improved significantly as a consequence of training. Listening to NV compared to clear speech activated left insula, and prefrontal and motor cortices. These areas, which are implicated in speech production, may play an active role in supporting the comprehension of degraded speech. Elevated activation in the precentral gyrus during paired clear-then-distorted presentations that enhance learning further suggests a role for articulatory representations of speech in perceptual learning of degraded speech.

Abstract

Alexithymia concerns a difficulty identifying and communicating one’s own emotions, and a tendency towards externally-oriented thinking. Recent work argues that such alexithymic traits are due to altered arousal response and poor subjective awareness of “objective” arousal responses. Although there are individual differences within the general population in identifying and describing emotions, extant research has focused on highly alexithymic individuals. Here we investigated whether mean arousal and concordance between subjective and objective arousal underpin individual differences in alexithymic traits in a general population sample. Participants rated subjective arousal responses to 60 images from the International Affective Picture System whilst their skin conductance was recorded. The Autism Quotient was employed to control for autistic traits in the general population. Analysis using linear models demonstrated that mean arousal significantly predicted Toronto Alexithymia Scale scores above and beyond autistic traits, but concordance scores did not. This indicates that, whilst objective arousal is a useful predictor in populations that are both above and below the cut-off values for alexithymia, concordance scores between objective and subjective arousal do not predict variation in alexithymic traits in the general population.

Abstract

Height-pitch associations are claimed to be universal and independent of language, but this claim remains controversial. The present study sheds new light on this debate with a multimodal analysis of individual sound and melody descriptions obtained in an interactive communication paradigm with speakers of Dutch and Farsi. The findings reveal that, in contrast to Dutch speakers, Farsi speakers do not use a height-pitch metaphor consistently in speech. Both Dutch and Farsi speakers’ co-speech gestures did reveal a mapping of higher pitches to higher space and lower pitches to lower space, and this gesture space-pitch mapping tended to co-occur with corresponding spatial words (high-low). However, this mapping was much weaker in Farsi speakers than Dutch speakers. This suggests that cross-linguistic differences shape the conceptualization of pitch and further calls into question the universality of height-pitch associations.

Abstract

The view put forward here is that visual bodily signals play a core role in human communication and the coordination of minds. Critically, this role goes far beyond referential and propositional meaning. The human communication system that we consider to be the explanandum in the evolution of language thus is not spoken language. It is, instead, a deeply multimodal, multilayered, multifunctional system that developed—and survived—owing to the extraordinary flexibility and adaptability that it endows us with. Beyond their undisputed iconic power, visual bodily signals (manual and head gestures, facial expressions, gaze, torso movements) fundamentally contribute to key pragmatic processes in modern human communication. This contribution becomes particularly evident with a focus that includes non-iconic manual signals, non-manual signals and signal combinations. Such a focus also needs to consider meaning encoded not just via iconic mappings, since kinematic modulations and interaction-bound meaning are additional properties equipping the body with striking pragmatic capacities. Some of these capacities, or its precursors, may have already been present in the last common ancestor we share with the great apes and may qualify as early versions of the components constituting the hypothesized interaction engine.

Abstract

The given-new contract entails that speakers must distinguish for their addressee whether references are new or already part of their dialogue. Past research had found that, in a monologue to a listener, speakers shortened repeated words. However, the notion of the given-new contract is inherently dialogic, with an addressee and the availability of co-speech gestures. Here, two face-to-face dialogue experiments tested whether gesture duration also follows the given-new contract. In Experiment 1, four experimental sequences confirmed that when speakers repeated their gestures, they shortened the duration significantly. Experiment 2 replicated the effect with spontaneous gestures in a different task. This experiment also extended earlier results with words, confirming that speakers shortened their repeated words significantly in a multimodal dialogue setting, the basic form of language use. Because words and gestures were not necessarily redundant, these results offer another instance in which gestures and words independently serve pragmatic requirements of dialogue.

Abstract

Abstract Neuroimaging has been extensively used to study brain structure and function in individuals with attention deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) over the past decades. Two of the main shortcomings of the neuroimaging literature of these disorders are the small sample sizes employed and the heterogeneity of methods used. In 2013 and 2014, the ENIGMA-ADHD and ENIGMA-ASD working groups were respectively, founded with a common goal to address these limitations. Here, we provide a narrative review of the thus far completed and still ongoing projects of these working groups. Due to an implicitly hierarchical psychiatric diagnostic classification system, the fields of ADHD and ASD have developed largely in isolation, despite the considerable overlap in the occurrence of the disorders. The collaboration between the ENIGMA-ADHD and -ASD working groups seeks to bring the neuroimaging efforts of the two disorders closer together. The outcomes of case–control studies of subcortical and cortical structures showed that subcortical volumes are similarly affected in ASD and ADHD, albeit with small effect sizes. Cortical analyses identified unique differences in each disorder, but also considerable overlap between the two, specifically in cortical thickness. Ongoing work is examining alternative research questions, such as brain laterality, prediction of case–control status, and anatomical heterogeneity. In brief, great strides have been made toward fulfilling the aims of the ENIGMA collaborations, while new ideas and follow-up analyses continue that include more imaging modalities (diffusion MRI and resting-state functional MRI), collaborations with other large databases, and samples with dual diagnoses.

Abstract

Background Reduced total brain volume is a consistent finding in children with Attention Deficit/Hyperactivity Disorder (ADHD). In order to get a better understanding of the neurobiology of ADHD, we take the first step in studying the dimensionality of current self-reported adult ADHD symptoms, by looking at its relation with total brain volume. Methodology/Principal Findings In a sample of 652 highly educated adults, the association between total brain volume, assessed with magnetic resonance imaging, and current number of self-reported ADHD symptoms was studied. The results showed an association between these self-reported ADHD symptoms and total brain volume. Post-hoc analysis revealed that the symptom domain of inattention had the strongest association with total brain volume. In addition, the threshold for impairment coincides with the threshold for brain volume reduction. Conclusions/Significance This finding improves our understanding of the biological substrates of self-reported ADHD symptoms, and suggests total brain volume as a target intermediate phenotype for future gene-finding in ADHD.

Abstract

We investigated 4- and 5-year-old children’s mapping strategies in a spatial task. Children were required to find a picture in an array of three identical cups after observing another picture being hidden in another array of three cups. The arrays were either aligned one behind the other in two rows or placed side by side forming one line. Moreover, children were rewarded for two different mapping strategies. Half of the children needed to choose a cup that held the same relative position as the rewarded cup in the other array; they needed to map left–left, middle–middle, and right–right cups together (aligned mapping), which required encoding and mapping of two relations (e.g., the cup left of the middle cup and left of the right cup). The other half needed to map together the cups that held the same relation to the table’s spatial features—the cups at the edges, the middle cups, and the cups in the middle of the table (landmark mapping)—which required encoding and mapping of one relation (e.g., the cup at the table’s edge). Results showed that children’s success was constellation dependent; performance was higher when the arrays were aligned one behind the other in two rows than when they were placed side by side. Furthermore, children showed a preference for landmark mapping over aligned mapping.

Abstract

When participants are presented simultaneously with spoken language and a visual display depicting objects to which that language refers, participants spontaneously fixate the visual referents of the words being heard [Cooper, R. M. (1974). The control of eye fixation by the meaning of spoken language: A new methodology for the real-time investigation of speech perception, memory, and language processing. Cognitive Psychology, 6(1), 84–107; Tanenhaus, M. K., Spivey-Knowlton, M. J., Eberhard, K. M., & Sedivy, J. C. (1995). Integration of visual and linguistic information in spoken language comprehension. Science, 268(5217), 1632–1634]. We demonstrate here that such spontaneous fixation can be driven by partial semantic overlap between a word and a visual object. Participants heard the word ‘piano’ when (a) a piano was depicted amongst unrelated distractors; (b) a trumpet was depicted amongst those same distractors; and (c), both the piano and trumpet were depicted. The probability of fixating the piano and the trumpet in the first two conditions rose as the word ‘piano’ unfolded. In the final condition, only fixations to the piano rose, although the trumpet was fixated more than the distractors. We conclude that eye movements are driven by the degree of match, along various dimensions that go beyond simple visual form, between a word and the mental representations of objects in the concurrent visual field.

Abstract

A recent trend in psycholinguistic research has been to posit prediction as an essential function of language processing. The present paper develops a linguistic perspective on viewing prediction in terms of pre-activation. We describe what predictions are and how they are produced. Our basic premises are that (a) no prediction can be made without knowledge to support it; and (b) it is therefore necessary to characterize the precise form of that knowledge, as revealed by a suitable theory of linguistic representations. We describe the Parallel Architecture (PA: Jackendoff, 2002; Jackendoff and Audring, 2020), which makes explicit our commitments about linguistic representations, and we develop an account of processing based on these representations. Crucial to our account is that what have been traditionally treated as derivational rules of grammar are formalized by the PA as lexical items, encoded in the same format as words. We then present a theory of prediction in these terms: linguistic input activates lexical items whose beginning (or incipit) corresponds to the input encountered so far; and prediction amounts to pre-activation of the as yet unheard parts of those lexical items (the remainder). Thus the generation of predictions is a natural byproduct of processing linguistic representations. We conclude that the PA perspective on pre-activation provides a plausible account of prediction in language processing that bridges linguistic and psycholinguistic theorizing.

Abstract

The experimental investigation of language-mediated visual attention is a promising way to study the interaction of the cognitive systems involved in language, vision, attention, and memory. Here we highlight four challenges for a mechanistic account of this oculomotor behavior: the levels of representation at which language-derived and vision-derived representations are integrated; attentional mechanisms; types of memory; and the degree of individual and group differences. Central points in our discussion are (a) the possibility that local microcircuitries involving feedforward and feedback loops instantiate a common representational substrate of linguistic and non-linguistic information and attention; and (b) that an explicit working memory may be central to explaining interactions between language and visual attention. We conclude that a synthesis of further experimental evidence from a variety of fields of inquiry and the testing of distinct, non-student, participant populations will prove to be critical.

Abstract

Typical adults read remarkably quickly. Such fast reading is facilitated by brain processes that are sensitive to both word frequency and contextual constraints. It is debated as to whether these attributes have additive or interactive effects on language processing in the brain. We investigated this issue by analysing existing magnetoencephalography data from 99 participants reading intact and scrambled sentences. Using a cross-validated model comparison scheme, we found that lexical frequency predicted the word-by-word elicited MEG signal in a widespread cortical network, irrespective of sentential context. In contrast, index (ordinal word position) was more strongly encoded in sentence words, in left front-temporal areas. This confirms that frequency influences word processing independently of predictability, and that contextual constraints affect word-by-word brain responses. With a conservative multiple comparisons correction, only the interaction between lexical frequency and surprisal survived, in anterior temporal and frontal cortex, and not between lexical frequency and entropy, nor between lexical frequency and index. However, interestingly, the uncorrected index*frequency interaction revealed an effect in left frontal and temporal cortex that reversed in time and space for intact compared to scrambled sentences. Finally, we provide evidence to suggest that, in sentences, lexical frequency and predictability may independently influence early (<150ms) and late stages of word processing, but interact during later stages of word processing (>150-250ms), thus helping to converge previous contradictory eye-tracking and electrophysiological literature. Current neuro-cognitive models of reading would benefit from accounting for these differing effects of lexical frequency and predictability on different stages of word processing.

Abstract

Traditional experiments indicate that prediction is important for efficient speech processing. In three virtual reality visual world paradigm experiments, we tested whether such findings hold in naturalistic settings (Experiment 1) and provided novel insights into whether disfluencies in speech (repairs/hesitations) inform one’s predictions in rich environments (Experiments 2–3). Experiment 1 supports that listeners predict upcoming speech in naturalistic environments, with higher proportions of anticipatory target fixations in predictable compared to unpredictable trials. In Experiments 2–3, disfluencies reduced anticipatory fixations towards predicted referents, compared to conjunction (Experiment 2) and fluent (Experiment 3) sentences. Unexpectedly, Experiment 2 provided no evidence that participants made new predictions from a repaired verb. Experiment 3 provided novel findings that fixations towards the speaker increase upon hearing a hesitation, supporting current theories of how hesitations influence sentence processing. Together, these findings unpack listeners’ use of visual (objects/speaker) and auditory (speech/disfluencies) information when predicting upcoming words.

Abstract

Being ostracized or excluded, even briefly and by strangers, is painful and threatens fundamental needs. Recent work by Zhong and Leonardelli (2008) found that excluded individuals perceive the room as cooler and that they desire warmer drinks. A perspective that many rely on in embodiment is the theoretical idea that people use metaphorical associations to understand social exclusion (see Landau, Meier, & Keefer, 2010). We suggest that people feel colder because they are colder. The results strongly support the idea that more complex metaphorical understandings of social relations are scaffolded onto literal changes in bodily temperature: Being excluded in an online ball tossing game leads to lower finger temperatures (Study 1), while the negative affect typically experienced after such social exclusion is alleviated after holding a cup of warm tea (Study 2). The authors discuss further implications for the interaction between body and social relations specifically, and for basic and cognitive systems in general.

Abstract

During aging, intracranial volume remains unchanged and represents maximally attained brain size, while various interacting biological phenomena lead to brain volume loss. Consequently, intracranial volume and brain volume in late life reflect different genetic influences. Our genome-wide association study (GWAS) in 8,175 community-dwelling elderly persons did not reveal any associations at genome-wide significance (P < 5 × 10(-8)) for brain volume. In contrast, intracranial volume was significantly associated with two loci: rs4273712 (P = 3.4 × 10(-11)), a known height-associated locus on chromosome 6q22, and rs9915547 (P = 1.5 × 10(-12)), localized to the inversion on chromosome 17q21. We replicated the associations of these loci with intracranial volume in a separate sample of 1,752 elderly persons (P = 1.1 × 10(-3) for 6q22 and 1.2 × 10(-3) for 17q21). Furthermore, we also found suggestive associations of the 17q21 locus with head circumference in 10,768 children (mean age of 14.5 months). Our data identify two loci associated with head size, with the inversion at 17q21 also likely to be involved in attaining maximal brain size.

Abstract

Stimulus-related changes in cerebral blood oxygenation were measured using high-resolution functional magnetic resonance imaging sequentially covering visual occipital areas in contiguous sections. During dynamic imaging, healthy subjects silently viewed pseudowords, single false fonts, or length-matched strings of the same false fonts. The paradigm consisted of a sixfold alternation of an activation and a control task. With pseudowords as activation vs single false fonts as control, responses were seen mainly in medial occipital cortex. These responses disappeared when pseudowords were alternated with false font strings as the control and reappeared when false font strings instead of pseudowords served as activation and were alternated with single false fonts. The string-length contrast alone, therefore, is sufficient to account for the activation pattern observed in medial visual cortex when word-like stimuli are contrasted with single characters.

Abstract

Infectious diseases exert a constant evolutionary pressure on the innate immunity genes. TLR4, an important member of the Toll-like receptors family, specifically recognizes conserved structures of various infectious pathogens. Two functional TLR4 polymorphisms, Asp299Gly and Thr399Ile, modulate innate host defense against infections, and their prevalence between various populations has been proposed to be influenced by local infectious pressures. If this assumption is true, strong local infectious pressures would lead to a homogeneous pattern of these ancient TLR4 polymorphisms in geographically close populations, while a weak selection or genetic drift may result in a diverse pattern. We evaluated TLR4 polymorphisms in 15 ethnic groups of Iran, to assess whether infections exerted selective pressures on different haplotypes containing these variants. The Iranian subpopulations displayed a heterogeneous pattern of TLR4 polymorphisms, comprising various percentages of Asp299Gly and Thr399Ile alone or in combination. The Iranian sample as a whole showed an intermediate mixed pattern when compared with commonly found patterns in Africa, Europe, Eastern Asia and Americas. These findings suggest a weak or absent selection pressure on TLR4 polymorphisms in the Middle-East, that does not support the assumption of an important role of these polymorphisms in the host defence against local pathogens.

Abstract

How individuals learn complex regularities in the environment and generalize them to new instances is a key question in cognitive science. Although previous investigations have advocated the idea that learning and generalizing depend upon separate processes, the same basic learning mechanisms may account for both. In language learning experiments, these mechanisms have typically been studied in isolation of broader cognitive phenomena such as memory, perception, and attention. Here, we show how learning and generalization in language is embedded in these broader theories by testing learners on their ability to chunk nonadjacent dependencies—a key structure in language but a challenge to theories that posit learning through the memorization of structure. In two studies, adult participants were trained and tested on an artificial language containing nonadjacent syllable dependencies, using a novel chunking-based serial recall task involving verbal repetition of target sequences (formed from learned strings) and scrambled foils. Participants recalled significantly more syllables, bigrams, trigrams, and nonadjacent dependencies from sequences conforming to the language’s statistics (both learned and generalized sequences). They also encoded and generalized specific nonadjacent chunk information. These results suggest that participants chunk remote dependencies and rapidly generalize this information to novel structures. The results thus provide further support for learning-based approaches to language acquisition, and link statistical learning to broader cognitive mechanisms of memory.

Abstract

Hereditary mixed polyposis syndrome (HMPS) is characterized by apparent autosomal dominant inheritance of multiple types of colorectal polyp, with colorectal carcinoma occurring in a high proportion of affected individuals. Here, we use genetic mapping, copy-number analysis, exclusion of mutations by high-throughput sequencing, gene expression analysis and functional assays to show that HMPS is caused by a duplication spanning the 3' end of the SCG5 gene and a region upstream of the GREM1 locus. This unusual mutation is associated with increased allele-specific GREM1 expression. Whereas GREM1 is expressed in intestinal subepithelial myofibroblasts in controls, GREM1 is predominantly expressed in the epithelium of the large bowel in individuals with HMPS. The HMPS duplication contains predicted enhancer elements; some of these interact with the GREM1 promoter and can drive gene expression in vitro. Increased GREM1 expression is predicted to cause reduced bone morphogenetic protein (BMP) pathway activity, a mechanism that also underlies tumorigenesis in juvenile polyposis of the large bowel.

Abstract

In this study, older adults monitored for pre-assigned target sounds in a target talker's speech in a quiet (no noise) condition and in a condition with competing-talker noise. The question was to which extent the impact of the competing-talker noise on performance could be predicted from individual hearing loss and from a cognitive measure of inhibitory abilities, i.e., a measure of Stroop interference. The results showed that the non-auditory measure of Stroop interference predicted the impact of distraction on performance, over and above the effect of hearing loss. This suggests that individual differences in inhibitory abilities among older adults relate to susceptibility to distracting speech.

Abstract

Microarrays provide a powerful analytical tool for the simultaneous detection of multiple pathogens. We developed diagnostic suspension microarrays for sensitive and specific detection of the biothreat pathogens Bacillus anthracis, Yersinia pestis, Francisella tularensis and Coxiella burnetii. Two assay chemistries for amplification and labeling were developed, one method using direct hybridization and the other using target-specific primer extension, combined with hybridization to universal arrays. Asymmetric PCR products for both assay chemistries were produced by using a multiplex asymmetric PCR amplifying 16 DNA signatures (16-plex). The performances of both assay chemistries were compared and their advantages and disadvantages are discussed. The developed microarrays detected multiple signature sequences and an internal control which made it possible to confidently identify the targeted pathogens and assess their virulence potential. The microarrays were highly specific and detected various strains of the targeted pathogens. Detection limits for the different pathogen signatures were similar or slightly higher compared to real-time PCR. Probit analysis showed that even a few genomic copies could be detected with 95% confidence. The microarrays detected DNA from different pathogens mixed in different ratios and from spiked or naturally contaminated samples. The assays that were developed have a potential for application in surveillance and diagnostics. © 2012 Janse et al.

Abstract

We investigated comprehension of and adaptation to speech in an unfamiliar accent in older adults. Participants performed a speeded sentence verification task for accented sentences: one group upon auditory-only presentation, and the other group upon audiovisual presentation. Our questions were whether audiovisual presentation would facilitate adaptation to the novel accent, and which cognitive and linguistic measures would predict adaptation. Participants were therefore tested on a range of background tests: hearing acuity, auditory verbal short-term memory, working memory, attention-switching control, selective attention, and vocabulary knowledge. Both auditory-only and audiovisual groups showed improved accuracy and decreasing response times over the course of the experiment, effectively showing accent adaptation. Even though the total amount of improvement was similar for the auditory-only and audiovisual groups, initial rate of adaptation was faster in the audiovisual group. Hearing sensitivity and short-term and working memory measures were associated with efficient processing of the novel accent. Analysis of the relationship between accent comprehension and the background tests revealed furthermore that selective attention and vocabulary size predicted the amount of adaptation over the course of the experiment. These results suggest that vocabulary knowledge and attentional abilities facilitate the attention-shifting strategies proposed to be required for perceptual learning.

Abstract

Rhythmic stimulation can be applied to modulate neuronal oscillations. Such ‘entrainment’ is optimized when stimulation frequency is individually calibrated based on magneto/encephalography markers. It remains unknown how consistent such individual markers are across days/sessions, within a session, or across cognitive states, hemispheres and estimation methods, especially in a realistic, practical, lab setting. We here estimated individual alpha frequency (IAF) repeatedly from short electroencephalography (EEG) measurements at rest or during an attention task (cognitive state), using single parieto-occipital electrodes in 24 participants on 4 days (between-sessions), with multiple measurements over an hour on 1 day (within-session). First, we introduce an algorithm to automatically reject power spectra without a sufficiently clear peak to ensure unbiased IAF estimations. Then we estimated IAF via the traditional ‘maximum’ method and a ‘Gaussian fit’ method. IAF was reliable within- and between-sessions for both cognitive states and hemispheres, though task-IAF estimates tended to be more variable. Overall, the ‘Gaussian fit’ method was more reliable than the ‘maximum’ method. Furthermore, we evaluated how far from an approximated ‘true’ task-related IAF the selected ‘stimulation frequency’ was, when calibrating this frequency based on a short rest-EEG, a short task-EEG, or simply selecting 10 Hz for all participants. For the ‘maximum’ method, rest-EEG calibration was best, followed by task-EEG, and then 10 Hz. For the ‘Gaussian fit’ method, rest-EEG and task-EEG-based calibration were similarly accurate, and better than 10 Hz. These results lead to concrete recommendations about valid, and automated, estimation of individual oscillation markers in experimental and clinical settings.

Abstract

Transcranial alternating current stimulation (tACS) can be used to study causal contributions of oscillatory brain mechanisms to cognition and behavior. For instance, individual alpha frequency (IAF) tACS was reported to enhance alpha power and impact visuospatial attention performance. Unfortunately, such results have been inconsistent and difficult to replicate. In tACS, stimulation generally involves one frequency, sometimes individually calibrated to a peak value observed in an M/EEG power spectrum. Yet, the ‘peak’ actually observed in such power spectra often contains a broader range of frequencies, raising the question whether a biologically calibrated tACS protocol containing this fuller range of alpha-band frequencies might be more effective. Here, we introduce ‘Broadband-alpha-tACS’, a complex individually calibrated electrical stimulation protocol. We band-pass filtered left posterior resting-state EEG data around the IAF (+/- 2 Hz), and converted that time series into an electrical waveform for tACS stimulation of that same left posterior parietal cortex location. In other words, we stimulated a brain region with a ‘replay’ of its own alpha-band frequency content, based on spontaneous activity. Within-subjects (N=24), we compared to a sham tACS session the effects of broadband-alpha tACS, power-matched spectral inverse (‘alpha-removed’) control tACS, and individual alpha frequency tACS, on EEG alpha power and performance in an endogenous attention task previously reported to be affected by alpha tACS. Broadband-alpha-tACS significantly modulated attention task performance (i.e., reduced the rightward visuospatial attention bias in trials without distractors, and reduced attention benefits). Alpha-removed tACS also reduced the rightward visuospatial attention bias. IAF-tACS did not significantly modulate attention task performance compared to sham tACS, but also did not statistically significantly differ from broadband-alpha-tACS. This new broadband-alpha tACS approach seems promising, but should be further explored and validated in future studies.

Abstract

This functional magnetic resonance imaging (fMRI) study investigates a crucial parameter in spatial description, namely variants in the frame of reference chosen. Two frames of reference are available in European languages for the description of small-scale assemblages, namely the intrinsic (or object-oriented) frame and the relative (or egocentric) frame. We showed participants a sentence such as “the ball is in front of the man”, ambiguous between the two frames, and then a picture of a scene with a ball and a man – participants had to respond by indicating whether the picture did or did not match the sentence. There were two blocks, in which we induced each frame of reference by feedback. Thus for the crucial test items, participants saw exactly the same sentence and the same picture but now from one perspective, now the other. Using this method, we were able to precisely pinpoint the pattern of neural activation associated with each linguistic interpretation of the ambiguity, while holding the perceptual stimuli constant. Increased brain activity in bilateral parahippocampal gyrus was associated with the intrinsic frame of reference whereas increased activity in the right superior frontal gyrus and in the parietal lobe was observed for the relative frame of reference. The study is among the few to show a distinctive pattern of neural activation for an abstract yet specific semantic parameter in language. It shows with special clarity the nature of the neural substrate supporting each frame of spatial reference

Abstract

A foundational assumption of human communication is that speakers should say as much as necessary, but no more. Yet, people routinely produce redundant adjectives and their propensity to do so varies cross-linguistically. Here, we propose a computational theory, whereby speakers create referential expressions designed to facilitate listeners’ reference resolution, as they process words in real time. We present a computational model of our account, the Incremental Collaborative Efficiency (ICE) model, which generates referential expressions by considering listeners’ real-time incremental processing and reference identification. We apply the ICE framework to physical reference, showing that listeners construct expressions designed to minimize listeners’ expected visual search effort during online language processing. Our model captures a number of known effects in the literature, including cross-linguistic differences in speakers’ propensity to over-specify. Moreover, the ICE model predicts graded acceptability judgments with quantitative accuracy, systematically outperforming an alternative, brevity-based model. Our findings suggest that physical reference production is best understood as driven by a collaborative goal to help the listener identify the intended referent, rather than by an egocentric effort to minimize utterance length.

Abstract

The QWERTY keyboard mediates communication for millions of language users. Here, we investigated whether differences in the way words are typed correspond to differences in their meanings. Some words are spelled with more letters on the right side of the keyboard and others with more letters on the left. In three experiments, we tested whether asymmetries in the way people interact with keys on the right and left of the keyboard influence their evaluations of the emotional valence of the words. We found the predicted relationship between emotional valence and QWERTY key position across three languages (English, Spanish, and Dutch). Words with more right-side letters were rated as more positive in valence, on average, than words with more left-side letters: the QWERTY effect. This effect was strongest in new words coined after QWERTY was invented and was also found in pseudowords. Although these data are correlational, the discovery of a similar pattern across languages, which was strongest in neologisms, suggests that the QWERTY keyboard is shaping the meanings of words as people filter language through their fingers. Widespread typing introduces a new mechanism by which semanntic changes in language can arise.