Publications

Abstract

Objective: To combine MRI-based cortical morphometry and diffusion white matter tractography to describe the anatomical correlates of repetition deficits in patients with primary progressive aphasia (PPA).

Methods: The traditional anatomical model of language identifies a network for word repetition that includes Wernicke and Broca regions directly connected via the arcuate fasciculus. Recent tractography findings of an indirect pathway between Wernicke and Broca regions suggest a critical role of the inferior parietal lobe for repetition. To test whether repetition deficits are associated with damage to the direct or indirect pathway between both regions, tractography analysis was performed in 30 patients with PPA (64.27 ± 8.51 years) and 22 healthy controls. Cortical volume measurements were also extracted from 8 perisylvian language areas connected by the direct and indirect pathways.

Results: Compared to healthy controls, patients with PPA presented with reduced performance in repetition tasks and increased damage to most of the perisylvian cortical regions and their connections through the indirect pathway. Repetition deficits were prominent in patients with cortical atrophy of the temporo-parietal region with volumetric reductions of the indirect pathway.

Conclusions: The results suggest that in PPA, deficits in repetition are due to damage to the temporo-parietal cortex and its connections to Wernicke and Broca regions. We therefore propose a revised language model that also includes an indirect pathway for repetition, which has important clinical implications for the functional mapping and treatment of neurologic patients.

Abstract

This scientific commentary refers to ‘Metabolic lesion-deficit mapping of human cognition’ by Jha etal.

Abstract

In speech, listeners extract continuously-varying spectrotemporal cues from the acoustic signal to perceive discrete phonetic categories. Spectral cues are spatially encoded in the amplitude of responses in phonetically-tuned neural populations in auditory cortex. It remains unknown whether similar neurophysiological mechanisms encode temporal cues like voice-onset time (VOT), which distinguishes sounds like /b/ and/p/. We used direct brain recordings in humans to investigate the neural encoding of temporal speech cues with a VOT continuum from /ba/ to /pa/. We found that distinct neural populations respond preferentially to VOTs from one phonetic category, and are also sensitive to sub-phonetic VOT differences within a population’s preferred category. In a simple neural network model, simulated populations tuned to detect either temporal gaps or coincidences between spectral cues captured encoding patterns observed in real neural data. These results demonstrate that a spatial/amplitude neural code underlies the cortical representation of both spectral and temporal speech cues.

Abstract

Turn on your affective system by tweaking your face muscles - or getting an eyeful of someone else doing the same.

Abstract

Find the fire that's cooking your memory systems.

Abstract

Emotions are powerful on the inside but often displayed in subtle ways on the outside. Are these displays culturally dependent or universal?

Abstract

Language perception studies on bilinguals often show that words that share form and meaning across languages (cognates) are easier to process than words that share only meaning. This facilitatory phenomenon is known as the cognate effect. Most previous studies have shown this effect visually, whereas the auditory modality as well as the interplay between type of similarity and modality remain largely unexplored. In this study, highly proficient late Spanish–English bilinguals carried out a lexical decision task in their second language, both visually and auditorily. Words had high or low phonological and orthographic similarity, fully crossed. We also included orthographically identical words (perfect cognates). Our results suggest that similarity in the same modality (i.e., orthographic similarity in the visual modality and phonological similarity in the auditory modality) leads to improved signal detection, whereas similarity across modalities hinders it. We provide support for the idea that perfect cognates are a special category within cognates. Results suggest a need for a conceptual and practical separation between types of similarity in cognate studies. The theoretical implication is that the representations of items are active in both modalities of the non-target language during language processing, which needs to be incorporated to our current processing models.

Abstract

Vocabulary learning occurs throughout the lifespan, often implicitly. For foreign language learners,
this is particularly challenging as they must acquire a large number of new words with little exposure.
In the present study, we explore the effects of contextual diversity—namely, the number of texts a
word appears in—on native and foreign language word learning. Participants read several texts that
had novel pseudowords replacing high-frequency words. The total number of encounters with the
novel words was held constant, but they appeared in 1, 2, 4, or 8 texts. In addition, some participants
read the texts in Spanish (their native language) and others in English (their foreign language). We
found that increasing contextual diversity improved recall and recognition of the word, as well as the
ability to match the word with its meaning while keeping comprehension unimpaired. Using a foreign
language only affected performance in the matching task, where participants had to quickly identify
the meaning of the word. Results are discussed in the greater context of the word learning and foreign
language literature as well as their importance as a teaching tool.

Abstract

Language perception studies on bilinguals often show that words that share form and meaning across
languages (cognates) are easier to process than words that share only meaning. This facilitatory
phenomenon is known as the cognate effect. Most previous studies have shown this effect visually,
whereas the auditory modality as well as the interplay between type of similarity and modality
remain largely unexplored. In this study, highly proficient late Spanish–English bilinguals carried out
a lexical decision task in their second language, both visually and auditorily. Words had high or low
phonological and orthographic similarity, fully crossed. We also included orthographically identical
words (perfect cognates). Our results suggest that similarity in the same modality (i.e., orthographic
similarity in the visual modality and phonological similarity in the auditory modality) leads to
improved signal detection, whereas similarity across modalities hinders it. We provide support for
the idea that perfect cognates are a special category within cognates. Results suggest a need for a
conceptual and practical separation between types of similarity in cognate studies. The theoretical
implication is that the representations of items are active in both modalities of the non‑target
language during language processing, which needs to be incorporated to our current processing
models.

Abstract

The current study focuses on how different scales with varying demands can
affect our subjective assessments. We carried out 2 experiments in which we
asked participants to rate how happy or sad morphed images of faces looked.
The two extremes were the original happy and original sad faces with 4
morphs in between. We manipulated language of the task—namely, half of
the participants carried it out in their native language, Spanish, and the other
half in their foreign language, English—and type of scale. Within type of
scale, we compared verbal and brightness scales. We found that, while
language did not have an effect on the assessment, type of scale did. The
brightness scale led to overall higher ratings, i.e., assessing all faces as
somewhat happier. This provides a limitation on the foreign language effect,
as well as evidence for the influence of the cognitive demands of a scale on
emotionality assessments.

Abstract

As knowing a foreign language becomes a necessity in the modern world, a large portion of
the population is faced with the challenge of learning a language in a classroom. This, in turn,
presents a unique set of difficulties. Acquiring a language with limited and artificial exposure makes
learning new information and vocabulary particularly difficult. The purpose of this thesis is to help us
understand how we can compensate—at least partially—for these difficulties by presenting
information in a way that aids learning. In particular, I focused on variables that affect semantic
richness—meaning the amount and variability of information associated with a word. Some factors
that affect semantic richness are intrinsic to the word and others pertain to that word’s relationship
with other items and information. This latter group depends on the context around the to-be-
learned items rather than the words themselves. These variables are easier to manipulate than
intrinsic qualities, making them more accessible tools for teaching and understanding learning. I
focused on two factors: emotionality of the surrounding semantic context and contextual diversity.
Publication 1 (Frances, de Bruin, et al., 2020b) focused on content learning in a foreign
language and whether the emotionality—positive or neutral—of the semantic context surrounding
key information aided its learning. This built on prior research that showed a reduction in
emotionality in a foreign language. Participants were taught information embedded in either
positive or neutral semantic contexts in either their native or foreign language. When they were
then tested on these embedded facts, participants’ performance decreased in the foreign language.
But, more importantly, they remembered better the information from the positive than the neutral
semantic contexts.
In Publication 2 (Frances, de Bruin, et al., 2020a), I focused on how emotionality affected
vocabulary learning. I taught participants the names of novel items described either in positive or
neutral terms in either their native or foreign language. Participants were then asked to recall and
recognize the object's name—when cued with its image. The effects of language varied with the
difficulty of the task—appearing in recall but not recognition tasks. Most importantly, learning the
words in a positive context improved learning, particularly of the association between the image of
the object and its name.
In Publication 3 (Frances, Martin, et al., 2020), I explored the effects of contextual
diversity—namely, the number of texts a word appears in—on native and foreign language word
learning. Participants read several texts that had novel pseudowords. The total number of
encounters with the novel words was held constant, but they appeared in 1, 2, 4, or 8 texts in either
their native or foreign language. Increasing contextual diversity—i.e., the number of texts a word
appeared in—improved recall and recognition, as well as the ability to match the word with its
meaning. Using a foreign language only affected performance when participants had to quickly
identify the meaning of the word.
Overall, I found that the tested contextual factors related to semantic richness—i.e.,
emotionality of the semantic context and contextual diversity—can be manipulated to improve
learning in a foreign language. Using positive emotionality not only improved learning in the foreign
language, but it did so to the same extent as in the native language. On a theoretical level, this
suggests that the reduction in emotionality in a foreign language is not ubiquitous and might relate
to the way in which that language as learned.
The third article shows an experimental manipulation of contextual diversity and how this
can affect learning of a lexical item, even if the amount of information known about the item is kept
constant. As in the case of emotionality, the effects of contextual diversity were also the same
between languages. Although deducing words from context is dependent on vocabulary size, this
does not seem to hinder the benefits of contextual diversity in the foreign language.
Finally, as a whole, the articles contained in this compendium provide evidence that some
aspects of semantic richness can be manipulated contextually to improve learning and memory. In
addition, the effects of these factors seem to be independent of language status—meaning, native
or foreign—when learning new content. This suggests that learning in a foreign and a native
language is not as different as I initially hypothesized, allowing us to take advantage of native
language learning tools in the foreign language, as well.

Abstract

Learning new content and vocabulary in a foreign language can be particularly difficult. Yet,
there are educational programs that require people to study in a language they are not
native speakers of. For this reason, it is important to understand how these learning processes work and possibly differ from native language learning, as well as to develop strategies to ease this process. The current study takes advantage of emotionality—operationally
defined as positive valence and high arousal—to improve memory. In two experiments, the
present paper addresses whether participants have more difficulty learning the names of
objects they have never seen before in their foreign language and whether embedding them
in a positive semantic context can help make learning easier. With this in mind, we had participants (with a minimum of a B2 level of English) in two experiments (43 participants in
Experiment 1 and 54 in Experiment 2) read descriptions of made-up objects—either positive
or neutral and either in their native or a foreign language. The effects of language varied
with the difficulty of the task and measure used. In both cases, learning the words in a positive context improved learning. Importantly, the effect of emotionality was not modulated by
language, suggesting that the effects of emotionality are independent of language and could
potentially be a useful tool for improving foreign language vocabulary learning.

Abstract

Family and twin studies consistently demonstrate a significant role for genetic factors in the aetiology of the reading disorder dyslexia. However, dyslexia is complex at both the genetic and phenotypic levels, and currently the nature of the core deficit or deficits remains uncertain. Traditional approaches for mapping disease genes, originally developed for single-gene disorders, have limited success when there is not a simple relationship between genotype and phenotype. Recent advances in high-throughput genotyping technology and quantitative statistical methods have made a new approach to identifying genes involved in complex disorders possible. The method involves assessing the genetic similarity of many sibling pairs along the lengths of all their chromosomes and attempting to correlate this similarity with that of their phenotypic scores. We are adopting this approach in an ongoing genome-wide search for genes involved in dyslexia susceptibility, and have already successfully applied the method by replicating results from previous studies suggesting that a quantitative trait locus at 6p21.3 influences reading disability.

Abstract

Several quantitative trait loci (QTLs) that influence developmental dyslexia (reading disability [RD]) have been mapped to chromosome regions by linkage analysis. The most consistently replicated area of linkage is on chromosome 6p23-21.3. We used association analysis in 223 siblings from the United Kingdom to identify an underlying QTL on 6p22.2. Our association study implicates a 77-kb region spanning the gene TTRAP and the first four exons of the neighboring uncharacterized gene KIAA0319. The region of association is also directly upstream of a third gene, THEM2. We found evidence of these associations in a second sample of siblings from the United Kingdom, as well as in an independent sample of twin-based sibships from Colorado. One main RD risk haplotype that has a frequency of ∼12% was found in both the U.K. and U.S. samples. The haplotype is not distinguished by any protein-coding polymorphisms, and, therefore, the functional variation may relate to gene expression. The QTL influences a broad range of reading-related cognitive abilities but has no significant impact on general cognitive performance in these samples. In addition, the QTL effect may be largely limited to the severe range of reading disability.

Abstract

Human behavioral asymmetries are commonly studied in the context of structural cortical and connectional asymmetries. Within this framework, Sreenivasan and Sridharan (1) provide intriguing evidence of a relationship between visual asymmetries and the lateralization of superior colliculi connections—a phylogenetically older mesencephalic structure. Specifically, response facilitation for cued locations (i.e., choice bias) in the contralateral hemifield was associated with differences in the connectivity of the superior colliculus. Given that the superior colliculus has a structural homolog—the optic tectum—which can be traced across all Vertebrata, these results may have meaningful evolutionary ramifications.

Abstract

Evolution, as we currently understand it, strikes a delicate balance between animals' ancestral history and adaptations to their current niche. Similarities between species are generally considered inherited from a common ancestor whereas observed differences are considered as more recent evolution. Hence comparing species can provide insights into the evolutionary history. Comparative neuroimaging has recently emerged as a novel subdiscipline, which uses magnetic resonance imaging (MRI) to identify similarities and differences in brain structure and function across species. Whereas invasive histological and molecular techniques are superior in spatial resolution, they are laborious, post-mortem, and oftentimes limited to specific species. Neuroimaging, by comparison, has the advantages of being applicable across species and allows for fast, whole-brain, repeatable, and multi-modal measurements of the structure and function in living brains and post-mortem tissue. In this review, we summarise the current state of the art in comparative anatomy and function of the brain and gather together the main scientific questions to be explored in the future of the fascinating new field of brain evolution derived from comparative neuroimaging.

Abstract

Gradients capture some of the variance of the resting-state functional magnetic resonance imaging (rsfMRI) signal. Amongst these, the principal gradient depicts a functional processing hierarchy that spans from sensory-motor cortices to regions of the default-mode network. While the cortex has been well characterised in terms of gradients little is known about its underlying white matter. For instance, comprehensive mapping of the principal gradient on the largest white matter tract, the corpus callosum, is still missing. Here, we mapped the principal gradient onto the midsection of the corpus callosum using the 7T human connectome project dataset. We further explored how quantitative measures and variability in callosal midsection connectivity relate to the principal gradient values. In so doing, we demonstrated that the extreme values of the principal gradient are located within the callosal genu and the posterior body, have lower connectivity variability but a larger spatial extent along the midsection of the corpus callosum than mid-range values. Our results shed light on the relationship between the brain's functional hierarchy and the corpus callosum. We further speculate about how these results may bridge the gap between functional hierarchy, brain asymmetries, and evolution.

Abstract

Language acquisition is complex. However, one thing that has been suggested to help learning is the way that information is distributed throughout language; co-occurrences among particular items (e.g., syllables and words) have been shown to help learners discover the words that a language contains and figure out how those words are used. Humans’ ability to draw on this information—“statistical learning”—has been demonstrated across a broad range of studies. However, evidence from non-WEIRD (Western, Educated, Industrialized, Rich, and Democratic) societies is critically lacking, which limits theorizing on the universality of this skill. We extended work on statistical language learning to a new, non-WEIRD linguistic population: speakers of Yélî Dnye, who live on a remote island off mainland Papua New Guinea (Rossel Island). We performed a replication of an existing statistical learning study, training adults on an artificial language with statistically defined words, then examining what they had learnt using a two-alternative forced-choice test. Crucially, we implemented several key amendments to the original study to ensure the replication was suitable for remote field-site testing with speakers of Yélî Dnye. We made critical changes to the stimuli and materials (to test speakers of Yélî Dnye, rather than English), the instructions (we re-worked these significantly, and added practice tasks to optimize participants’ understanding), and the study format (shifting from a lab-based to a portable tablet-based setup). We discuss the requirement for acute sensitivity to linguistic, cultural, and environmental factors when adapting studies to test new populations.

Abstract

High frequency words play a key role in language acquisition, with recent work suggesting they may serve both speech segmentation and lexical categorisation. However, it is not yet known whether infants can detect novel high frequency words in continuous speech, nor whether they can use them to help learning for segmentation and categorisation at the same time. For instance, when hearing “you eat the biscuit”, can children use the high-frequency words “you” and “the” to segment out “eat” and “biscuit”, and determine their respective lexical categories? We tested this in two experiments. In Experiment 1, we familiarised 12-month-old infants with continuous artificial speech comprising repetitions of target words, which were preceded by high-frequency marker words that distinguished the targets into two distributional categories. In Experiment 2, we repeated the task using the same language but with additional phonological cues to word and category structure. In both studies, we measured learning with head-turn preference tests of segmentation and categorisation, and compared performance against a control group that heard the artificial speech without the marker words (i.e., just the targets). There was no evidence that high frequency words helped either speech segmentation or grammatical categorisation. However, segmentation was seen to improve when the distributional information was supplemented with phonological cues (Experiment 2). In both experiments, exploratory analysis indicated that infants’ looking behaviour was related to their linguistic maturity (indexed by infants’ vocabulary scores) with infants with high versus low vocabulary scores displaying novelty and familiarity preferences, respectively. We propose that high-frequency words must reach a critical threshold of familiarity before they can be of significant benefit to learning.

Abstract

To acquire language, infants must learn how to identify words and linguistic structure in speech. Statistical learning has been suggested to assist both of these tasks. However, infants’ capacity to use statistics to discover words and structure together remains unclear. Further, it is not yet known how infants’ statistical learning ability relates to their language development. We trained 17-month-old infants on an artificial language comprising non-adjacent dependencies, and examined their looking times on tasks assessing sensitivity to words and structure using an eye-tracked head-turn-preference paradigm. We measured infants’ vocabulary size using a Communicative Development Inventory (CDI) concurrently and at 19, 21, 24, 25, 27, and 30 months to relate performance to language development. Infants could segment the words from speech, demonstrated by a significant difference in looking times to words versus part-words. Infants’ segmentation performance was significantly related to their vocabulary size (receptive and expressive) both currently, and over time (receptive until 24 months, expressive until 30 months), but was not related to the rate of vocabulary growth. The data also suggest infants may have developed sensitivity to generalised structure, indicating similar statistical learning mechanisms may contribute to the discovery of words and structure in speech, but this was not related to vocabulary size.

Abstract

Acquiring language is notoriously complex, yet for the majority of children this feat is accomplished with remarkable ease. Usage-based accounts of language acquisition suggest that this success can be largely attributed to the wealth of experience with language that children accumulate over the course of language acquisition. One field of research that is heavily underpinned by this principle of experience is statistical learning, which posits that learners can perform powerful computations over the distribution of information in a given input, which can help them to discern precisely how that input is structured, and how it operates. A growing body of work brings this notion to bear in the field of language acquisition, due to a developing understanding of the richness of the statistical information contained in speech. In this chapter we discuss the role that statistical learning plays in language acquisition, emphasising the importance of both the distribution of information within language, and the situation in which language is being learnt. First, we address the types of statistical learning that apply to a range of language learning tasks, asking whether the statistical processes purported to support language learning are the same or distinct across different tasks in language acquisition. Second, we expand the perspective on what counts as environmental input, by determining how statistical learning operates over the situated learning environment, and not just sequences of sounds in utterances. Finally, we address the role of variability in children’s input, and examine how statistical learning can accommodate (and perhaps even exploit) this during language acquisition.

Abstract

Background: Two distinct insomnia disorder (ID) phenotypes have been proposed, distinguished on the basis of an objective total sleep time less or more than 6 hr. In particular, it has been recently reported that patients with objective short sleep duration have a blunted response to cognitive behavioral therapy for insomnia (CBT-I). The aim of this study was to investigate the differences of CBT-I response in two groups of ID patients subdivided according to total sleep time. Methods: Two hundred forty-six ID patients were subdivided into two groups, depending on their reported total sleep time (TST) assessed by sleep diaries. Patients with a TST greater than 6 hr were classified as “normal sleepers” (NS), while those with a total sleep time less than 6 hr were classified as “short sleepers” (SS). Results: The delta between Insomnia Severity Index scores and sleep efficiency at the beginning as compared to the end of the treatment was significantly higher for SS in comparison to NS, even if they still exhibit more insomnia symptoms. No difference was found between groups in terms of remitters; however, more responders were observed in the SS group in comparison to the NS group. Conclusions: Our results demonstrate that ID patients with reported short total sleep time had a beneficial response to CBT-I of greater magnitude in comparison to NS. However, these patients may still experience the presence of residual insomnia symptoms after treatment.

Abstract

Graph neural networks (GNNs) have emerged as the standard method for numerous tasks on graph-structured data such as node classification. However, real-world graphs are often evolving over time and even new classes may arise. We model these challenges as an instance of lifelong learning, in which a learner faces a sequence of tasks and may take over knowledge acquired in past tasks. Such knowledge may be stored explicitly as historic data or implicitly within model parameters. In this work, we systematically analyze the influence of implicit and explicit knowledge. Therefore, we present an incremental training method for lifelong learning on graphs and introduce a new measure based on k-neighborhood time differences to address variances in the historic data. We apply our training method to five representative GNN architectures and evaluate them on three new lifelong node classification datasets. Our results show that no more than 50% of the GNN's receptive field is necessary to retain at least 95% accuracy compared to training over the complete history of the graph data. Furthermore, our experiments confirm that implicit knowledge becomes more important when fewer explicit knowledge is available.

Abstract

COVID-19 research datasets are crucial for analyzing research dynamics. Most collections of COVID-19 research items do not to include cited works and do not have annotations
from a controlled vocabulary. Starting with ZB MED KE data on COVID-19, which comprises CORD-19, we assemble a new dataset that includes cited work and MeSH annotations for all records. Furthermore, we conduct experiments on the analysis of research dynamics, in which we investigate predicting links in a co-annotation graph created on the basis of the new dataset. Surprisingly, we find that simple heuristic methods are better at
predicting future links than more sophisticated approaches such as graph neural networks.

Abstract

Visuospatial attention theories often propose hemispheric asymmetries underlying the control of attention. In general support of these theories, previous EEG/MEG studies have shown that spatial attention is associated with hemispheric modulation of posterior alpha power (gating by inhibition). However, since measures of alpha power are typically expressed as lateralization scores, or collapsed across left and right attention shifts, the individual hemispheric contribution to the attentional control mechanism remains unclear. This is, however, the most crucial and decisive aspect in which the currently competing attention theories continue to disagree. To resolve this long-standing conflict, we derived predictions regarding alpha power modulations from Heilman's hemispatial theory and Kinsbourne's interhemispheric competition theory and tested them empirically in an EEG experiment. We used an attention paradigm capable of isolating alpha power modulation in two attentional states, namely attentional bias in a neutral cue condition and spatial orienting following directional cues. Differential alpha modulations were found for both hemispheres across conditions. When anticipating peripheral visual targets without preceding directional cues (neutral condition), posterior alpha power in the left hemisphere was generally lower and more strongly modulated than in the right hemisphere, in line with the interhemispheric competition theory. Intriguingly, however, while alpha power in the right hemisphere was modulated by both, cue-directed leftward and rightward attention shifts, the left hemisphere only showed modulations by rightward shifts of spatial attention, in line with the hemispatial theory. This suggests that the two theories may not be mutually exclusive, but rather apply to different attentional states.

Abstract

We investigated whether Tagalog-speaking children incrementally interpret the first noun
as the agent, even if verbal and nominal markers for assigning thematic roles are given
early in Tagalog sentences. We asked five- and seven-year-old children and adult
controls to select which of two pictures of reversible actions matched the sentence they
heard, while their looks to the pictures were tracked. Accuracy and eye-tracking data
showed that agent-initial sentences were easier to comprehend than patient-initial
sentences, but the effect of word order was modulated by voice. Moreover, our eyetracking
data provided evidence that, by the first noun phrase, seven-year-old children
looked more to the target in the agent-initial compared to the patient-initial conditions,
but this word order advantage was no longer observed by the second noun phrase. The
findings support language processing and acquisition models which emphasize the role
of frequency in developing heuristic strategies (e.g., Chang, Dell, & Bock, 2006).

Abstract

Children must necessarily process their input in order to learn it, yet the architecture of the developing parsing system and how it interfaces with acquisition is unclear. In the current paper we report experimental and corpus data investigating adult and children's use of morphosyntactic cues for making incremental online predictions of thematic roles in Tagalog, a verb-initial symmetrical voice language of the Philippines. In Study 1, Tagalog-speaking adults completed a visual world eye-tracking experiment in which they viewed pictures of causative actions that were described by transitive sentences manipulated for voice and word order. The pattern of results showed that adults process agent and patient voice differently, predicting the upcoming noun in the patient voice but not in the agent voice, consistent with the observation of a patient voice preference in adult sentence production. In Study 2, our analysis of a corpus of child-directed speech showed that children heard more patient voice- than agent voice-marked verbs. In Study 3, 5-, 7-, and 9-year-old children completed a similar eye-tracking task as used in Study 1. The overall pattern of results suggested that, like the adults in Study 1, children process agent and patient voice differently in a manner that reflects the input distributions, with children developing towards the adult state across early childhood. The results are most consistent with theoretical accounts that identify a key role for input distributions in acquisition and language processing

Abstract

We report on two experiments that investigated the acquisition of the Tagalog symmetrical voice system, a typologically rare feature of Western Austronesian languages in which there are more than one basic transitive construction and no preference for agents to be syntactic subjects. In the experiments, 3-, 5-, and 7-year-old Tagalog-speaking children and adults completed a structural priming task that manipulated voice and word order, with the uniqueness of Tagalog allowing us to tease apart priming of thematic role order from that of syntactic roles. Participants heard a description of a picture showing a transitive action, and were then asked to complete a sentence of an unrelated picture using a voice-marked verb provided by the experimenter. Our results show that children gradually acquire an agent-before-patient preference, instead of having a default mapping of the agent to the first noun position. We also found an earlier mastery of the patient voice verbal and nominal marker configuration (patient is the subject), suggesting that children do not initially map the agent to the subject. Children were primed by thematic role but not syntactic role order, suggesting that they prioritize mapping of the thematic roles to sentence positions.

Abstract

Acoustic allometry is the study of how animal vocalisations reflect their body size. A key aim of this research is to identify outliers to acoustic allometry principles and pinpoint the evolutionary origins of such outliers. A parallel strand of research investigates species capable of vocal learning, the experience-driven ability to produce novel vocal signals through imitation or modification of existing vocalisations. Modification of vocalizations is a common feature found when studying both acoustic allometry and vocal learning. Yet, these two fields have only been investigated separately to date. Here, we review and connect acoustic allometry and vocal learning across mammalian clades, combining perspectives from bioacoustics, anatomy and evolutionary biology. Based on this, we hypothesize that, as a precursor to vocal learning, some species might have evolved the capacity for volitional vocal modulation via sexual selection for ‘dishonest’ signalling. We provide preliminary support for our hypothesis by showing significant associations between allometric deviation and vocal learning in a dataset of 164 mammals. Our work offers a testable framework for future empirical research linking allometric principles with the evolution of vocal learning.

Abstract

Communicating species identity is a key component of many animal signals. However, whether selection for species recognition systematically increases signal diversity during clade radiation remains debated. Here we show that in woodpecker drumming, a rhythmic signal used during mating and territorial defense, the amount of species identity information encoded remained stable during woodpeckers’ radiation. Acoustic analyses and evolutionary reconstructions show interchange among six main drumming types despite strong phylogenetic contingencies, suggesting evolutionary tinkering of drumming structure within a constrained acoustic space. Playback experiments and quantification of species discriminability demonstrate sufficient signal differentiation to support species recognition in local communities. Finally, we only find character displacement in the rare cases where sympatric species are also closely related. Overall, our results illustrate how historical contingencies and ecological interactions can promote conservatism in signals during a clade radiation without impairing the effectiveness of information transfer relevant to inter-specific discrimination.

Abstract

Social factors play a crucial role in the advancement of science. New findings are discussed and theories emerge through social interactions, which usually take place within local research groups and at academic events such as conferences, seminars, or workshops. This system tends to amplify the voices of a select subset of the community—especially more established researchers—thus limiting opportunities for the larger community to contribute and connect. Brainhack (https://brainhack.org/) events (or Brainhacks for short) complement these formats in neuroscience with decentralized 2- to 5-day gatherings, in which participants from diverse backgrounds and career stages collaborate and learn from each other in an informal setting. The Brainhack format was introduced in a previous publication (Cameron Craddock et al., 2016; Figures 1A and 1B). It is inspired by the hackathon model (see glossary in Table 1), which originated in software development and has gained traction in science as a way to bring people together for collaborative work and educational courses. Unlike many hackathons, Brainhacks welcome participants from all disciplines and with any level of experience—from those who have never written a line of code to software developers and expert neuroscientists. Brainhacks additionally replace the sometimes-competitive context of traditional hackathons with a purely collaborative one and also feature informal dissemination of ongoing research through unconferences.

Abstract

Processing of recursion has been proposed as the foundation of human linguistic ability. Yet this ability may be shared with other domains, such as the musical or rhythmic domain. Lindenmayer grammars (L-systems) have been proposed as a recursive grammar for use in artificial grammar experiments to test recursive processing abilities, and previous work had shown that participants are able to learn such a grammar using linguistic stimuli (syllables). In the present work, we used two experimental paradigms (a yes/no task and a two-alternative forced choice) to test whether adult participants are able to learn a recursive Lindenmayer grammar composed of drum sounds. After a brief exposure phase, we found that participants at the group level were sensitive to the exposure grammar and capable of distinguishing the grammatical and ungrammatical test strings above chance level in both tasks. While we found evidence of participants’ sensitivity to a very complex L-system grammar in a non-linguistic, potentially musical domain, the results were not robust. We discuss the discrepancy within our results and with the previous literature using L-systems in the linguistic domain. Furthermore, we propose directions for future music cognition research using L-system grammars.

Abstract

Tropical ecosystems are known for high species diversity. Adaptations permitting niche differentiation enable species to coexist. Historically, research focused primarily on morphological and behavioral adaptations for foraging, roosting, and other basic ecological factors. Another important factor, however, is differences in sensory capabilities. So far, studies mainly have focused on the output of behavioral strategies of predators and their prey preference. Understanding the coexistence of different foraging strategies, however, requires understanding underlying cognitive and neural mechanisms. In this study, we investigate hearing in bats and how it shapes bat species coexistence. We present the hearing thresholds and echolocation calls of 12 different gleaning bats from the ecologically diverse Phyllostomid family. We measured their auditory brainstem responses to assess their hearing sensitivity. The audiograms of these species had similar overall shapes but differed substantially for frequencies below 9 kHz and in the frequency range of their echolocation calls. Our results suggest that differences among bats in hearing abilities contribute to the diversity in foraging strategies of gleaning bats. We argue that differences in auditory sensitivity could be important mechanisms shaping diversity in sensory niches and coexistence of species.

Abstract

A key function of attention is to select an appropriate subset of available information by facilitation of attended processes and/or inhibition of irrelevant processing. Functional imaging studies, using positron emission tomography, have during different experimental tasks revealed decreased neuronal activity in areas that process input from unattended sensory modalities. It has been hypothesized that these decreases reflect a selective inhibitory modulation of nonrelevant cortical processing. In this study we addressed this question using a continuous arithmetical task with and without concomitant disturbing auditory input (task-irrelevant speech). During the arithmetical task, irrelevant speech did not affect task-performance but yielded decreased activity in the auditory and midcingulate cortices and increased activity in the left posterior parietal cortex. This pattern of modulation is consistent with a top down inhibitory modulation of a nonattended input to the auditory cortex and a coexisting, attention-based facilitation of taskrelevant processing in higher order cortices. These findings suggest that task-related decreases in cortical activity may be of functional importance in the understanding of both attentional mechanisms and taskrelated information processing.

Abstract

Developmental dyslexia (DD) is a learning disorder affecting the ability to read, with a heritability of 40–60%. A notable part of this heritability remains unexplained, and large genetic studies are warranted to identify new susceptibility genes and clarify the genetic bases of dyslexia. We carried out a genome-wide association study (GWAS) on 2274 dyslexia cases and 6272 controls, testing associations at the single variant, gene, and pathway level, and estimating heritability using single-nucleotide polymorphism (SNP) data. We also calculated polygenic scores (PGSs) based on large-scale GWAS data for different neuropsychiatric disorders and cortical brain measures, educational attainment, and fluid intelligence, testing them for association with dyslexia status in our sample. We observed statistically significant (p  < 2.8 × 10−6) enrichment of associations at the gene level, for LOC388780 (20p13; uncharacterized gene), and for VEPH1 (3q25), a gene implicated in brain development. We estimated an SNP-based heritability of 20–25% for DD, and observed significant associations of dyslexia risk with PGSs for attention deficit hyperactivity disorder (at pT = 0.05 in the training GWAS: OR = 1.23[1.16; 1.30] per standard deviation increase; p  = 8 × 10−13), bipolar disorder (1.53[1.44; 1.63]; p = 1 × 10−43), schizophrenia (1.36[1.28; 1.45]; p = 4 × 10−22), psychiatric cross-disorder susceptibility (1.23[1.16; 1.30]; p = 3 × 10−12), cortical thickness of the transverse temporal gyrus (0.90[0.86; 0.96]; p = 5 × 10−4), educational attainment (0.86[0.82; 0.91]; p = 2 × 10−7), and intelligence (0.72[0.68; 0.76]; p = 9 × 10−29). This study suggests an important contribution of common genetic variants to dyslexia risk, and novel genomic overlaps with psychiatric conditions like bipolar disorder, schizophrenia, and cross-disorder susceptibility. Moreover, it revealed the presence of shared genetic foundations with a neural correlate previously implicated in dyslexia by neuroimaging evidence.

Abstract

Regional variation in African-American English (AAE) is especially salient to its speakers involved with hip-hop culture, as hip-hop assigns great importance to regional identity and regional accents are a key means of expressing regional identity. However, little is known about AAE regional variation regarding prosodic rhythm and melody. In hip-hop music, regional variation can also be observed, with different regions’ rap performances being characterized by distinct “flows” (i.e., rhythmic and melodic delivery), an observation which has not been quantitatively investigated yet. This study concerns regional variation in AAE speech and rap, specifically regarding the United States’ East and West Coasts. It investigates how East Coast and West Coast AAE prosody are distinct, how East Coast and West Coast rap flows differ, and whether the two domains follow a similar pattern: more rhythmic and melodic variation on the West Coast compared to the East Coast for both speech and rap. To this end, free speech and rap recordings of 16 prominent African-American members of the East Coast and West Coast hip-hop communities were phonetically analyzed regarding rhythm (e.g., syllable isochrony and musical timing) and melody (i.e., pitch fluctuation) using a combination of existing and novel methodological approaches. The results mostly confirm the hypotheses that East Coast AAE speech and rap are less rhythmically diverse and more monotone than West Coast AAE speech and rap, respectively. They also show that regional variation in AAE prosody and rap flows pattern in similar ways, suggesting a connection between rhythm and melody in language and music.

Abstract

Irrelevant speech impairs the immediate serial recall of visually presented material. Previously, we have shown that the irrelevant speech effect (ISE) was associated with a relative decrease of regional blood flow in cortical regions subserving the verbal working memory, in particular the superior temporal cortex. In this extension of the previous study, the working memory load was increased and an increased activity as a response to irrelevant speech was noted in the dorsolateral prefrontal cortex. We suggest that the two studies together provide some basic insights as to the nature of the irrelevant speech effect. Firstly, no area in the brain can be ascribed as the single locus of the irrelevant speech effect. Instead, the functional neuroanatomical substrate to the effect can be characterized in terms of changes in networks of functionally interrelated areas. Secondly, the areas that are sensitive to the irrelevant speech effect are also generically activated by the verbal working memory task itself. Finally, the impact of irrelevant speech and related brain activity depends on working memory load as indicated by the differences between the present and the previous study. From a brain perspective, the irrelevant speech effect may represent a complex phenomenon that is a composite of several underlying mechanisms, which depending on the working memory load, include top-down inhibition as well as recruitment of compensatory support and control processes. We suggest that, in the low-load condition, a selection process by an inhibitory top-down modulation is sufficient, whereas in the high-load condition, at or above working memory span, auxiliary adaptive cognitive resources are recruited as compensation

Abstract

Comparative thanatology encompasses the study of death-related responses in non-human animals and aspires to elucidate the evolutionary origins of human behavior in the context of death. Many reports have revealed that humans are not the only species affected by the death of group members. Non-human primates in particular show behaviors such as congregating around the deceased, carrying the corpse for prolonged periods of time (predominantly mothers carrying dead infants), and inspecting the corpse for signs of life. Here, we extend the focus on death-related responses in non-human animals by exploring whether chimpanzees are inclined to console the bereaved: the individual(s) most closely associated with the deceased. We report a case in which a chimpanzee (Pan troglodytes) mother experienced the loss of her fully developed infant (presumed stillborn). Using observational data to compare the group members’ behavior before and after the death, we found that a substantial number of group members selectively increased their affiliative expressions toward the bereaved mother. Moreover, on the day of the death, we observed heightened expressions of species-typical reassurance behaviors toward the bereaved mother. After ruling out several alternative explanations, we propose that many of the chimpanzees consoled the bereaved mother by means of affiliative and selective empathetic expressions.

Abstract

The present article examines the proposal that typology is a major factor guiding transfer selectivity in L3/Ln acquisition. We tested first exposure in L3/Ln using two artificial languages (ALs) lexically based in English and Spanish, focusing on gender agreement between determiners and nouns, and between nouns and adjectives. 50 L1 Spanish-L2 English speakers took part in the experiment. After receiving implicit training in one of the ALs (Mini-Spanish, N = 26; Mini-English, N = 24), gender violations elicited a fronto-lateral negativity in Mini-English in the earliest time window (200–500 ms), although this was not followed by any other differences in subsequent periods. This effect was highly localized, surfacing only in electrodes of the right-anterior region. In contrast, gender violations in Mini-Spanish elicited a broadly distributed positivity in the 300–600 ms time window. While we do not find typical indices of grammatical processing such as the P600 component, we believe that the between-groups differential appearance of the positivity for gender violations in the 300–600 ms time window reflects differential allocation of attentional resources as a function of the ALs’ lexical similarity to English or Spanish. We take these differences in attention to be precursors of the processes involved in transfer source selection in L3/Ln.

Abstract

Semantic verbal fluency tasks are commonly used in neuropsychological assessment. Investigations of the influence of level of literacy have not yielded consistent results in the literature. This prompted us to investigate the ecological relevance of task specifics, in particular, the choice of semantic criteria used. Two groups of literate and illiterate subjects were compared on two verbal fluency tasks using different semantic criteria. The performance on a food criterion (supermarket fluency task), considered more ecologically relevant for the two literacy groups, and an animal criterion (animal fluency task) were compared. The data were analysed using both quantitative and qualitative measures. The quantitative analysis indicated that the two literacy groups performed equally well on the supermarket fluency task. In contrast, results differed significantly during the animal fluency task. The qualitative analyses indicated differences between groups related to the strategies used, especially with respect to the animal fluency task. The overall results suggest that there is not a substantial difference between literate and illiterate subjects related to the fundamental workings of semantic memory. However, there is indication that the content of semantic memory reflects differences in shared cultural background - in other words, formal education –, as indicated by the significant interaction between level of literacy and semantic criterion.

Abstract

Humans associate abstract words with physical stimulus dimensions, such as linking upward locations with positive concepts (e.g., happy = up). These associations manifest both via subjective reports of associations and on objective performance metrics. Humans also report subjective associations between colours and abstract words (e.g., joy is linked to yellow). Here we tested whether such associations manifest on objective task performance, even when not task-relevant. Across three experiments, participants were presented with abstract words in physical colours that were either congruent with previously-reported subjective word-colour associations (e.g., victory in red and unhappy in blue), or were incongruent (e.g., victory in blue and unhappy in red). In Experiment 1, participants' task was to identify the valence of words. This congruency manipulation systematically affected objective task performance. In Experiment 2, participants completed two blocks, a valence-identification and a colour-identification task block. Both tasks produced congruency effects on performance, however, the results of the colour identification block could have reflected learning effects (i.e., associating the more common congruent colour with the word). This issue was rectified in Experiment 3, whereby participants completed the same two tasks as Experiment 2, but now matched congruent and incongruent pairs were used for both tasks. Again, both tasks produced reliable congruency effects. Item analyses in each experiment revealed that these effects demonstrated a degree of item specificity. Overall, there was clear evidence that at least some abstract word-colour pairings can systematically affect behaviour.

Abstract

The development of rhythmicity is foundational to communicative and social behaviours in humans and many other species, and mechanisms of synchrony could be conserved across species. The goal of the current paper is to explore evolutionary hypotheses linking vocal learning and beat synchronization through genomic approaches, testing the prediction that genetic underpinnings of birdsong also contribute to the aetiology of human interactions with musical beat structure. We combined state-of-the-art-genomic datasets that account for underlying polygenicity of these traits: birdsong genome-wide transcriptomics linked to singing in zebra finches, and a human genome-wide association study of beat synchronization. Results of competitive gene set analysis revealed that the genetic architecture of human beat synchronization is significantly enriched for birdsong genes expressed in songbird Area X (a key nucleus for vocal learning, and homologous to human basal ganglia). These findings complement ethological and neural evidence of the relationship between vocal learning and beat synchronization, supporting a framework of some degree of common genomic substrates underlying rhythm-related behaviours in two clades, humans and songbirds (the largest evolutionary radiation of vocal learners). Future cross-species approaches investigating the genetic underpinnings of beat synchronization in a broad evolutionary context are discussed.

Abstract

Background: While persons with aphasia (PwA) are often dichotomised as fluent or nonfluent, agreement that fluency is not an all-or-nothing construct has led to the use of continuous variables as a way to quantify fluency, such as multi-dimensional rating scales, speech rate, and utterance length. Though these measures are often used in research, they provide little information about the underlying fluency deficit.
Aim: The aim of the study was to identify how well commonly used continuous measures of fluency capture variability in spontaneous speech variables at lexical, grammatical, and speech production levels. Methods & Procedures: Speech samples of 254 English-speaking PwA from the AphasiaBank database were analyzed to examine the distributions of four continuous measures of fluency: the WAB-R fluency scale, utterance length, retracing, and speech rate. Linear regression was used to identify spontaneous speech predictors contributing to each fluency outcome measure.
Outcomes & Results: All the outcome measures reflected the influence of multiple underlying dimensions, although the predictors varied. The WAB-R fluency scale, speech rate, and retracing were influenced by measures of grammatical competence, lexical retrieval, and speech production, whereas utterance length was influenced only by measures of grammatical competence and lexical retrieval. The strongest predictor of WAB-R fluency was aphasia severity, whereas the strongest predictor for all other fluency proxy measures was grammatical complexity.
Conclusions: Continuous measures allow a variety of ways to objectively quantify speech fluency; however, they reflect superficial manifestations of fluency that may be affected by multiple underlying deficits. Furthermore, the deficits underlying different measures vary, which may reduce the reliability of fluency diagnoses. Capturing these differences at the individual level is critical to accurate diagnosis and appropriately targeted therapy.

Abstract

Our aim in the present study is to measure neural correlates during spontaneous interactive sentence production. We present a novel approach using the word-by-word technique from improvisational theatre, in which two speakers jointly produce one sentence. This paradigm allows the assessment of behavioural aspects, such as turn-times, and electrophysiological responses, such as event-related-potentials (ERPs). Twenty-five participants constructed a cued but spontaneous four-word German sentence together with a confederate, taking turns for each word of the sentence. In 30% of the trials, the confederate uttered an unexpected gender-marked article. To complete the sentence in a meaningful way, the participant had to detect the violation and retrieve and utter a new fitting response. We found significant increases in response times after unexpected words and – despite allowing unscripted language production and naturally varying speech material – successfully detected significant N400 and P600 ERP effects for the unexpected word. The N400 EEG activity further significantly predicted the response time of the subsequent turn. Our results show that combining behavioural and neuroscientific measures of verbal interactions while retaining sufficient experimental control is possible, and that this combination provides promising insights into the mechanisms of spontaneous spoken dialogue.

Abstract

Children who have knowledge of two languages may show better phonological awareness than their monolingual peers (e.g. Bruck & Genesee, 1995). It remains unclear how much bilingual experience is needed for such advantages to appear, and whether differences in language or cognitive skills alter the relation between bilingualism and phonological awareness. These questions were investigated in this cross-sectional study. Participants (n = 294; 4–7 year-olds, in the first three grades of primary school) were Dutch-speaking pupils attending mainstream monolingual Dutch primary schools or early-English schools providing English lessons from grade 1, and simultaneous Dutch-English bilinguals. We investigated phonological awareness (rhyming, phoneme blending, onset phoneme identification, and phoneme deletion) and its relation to age, Dutch vocabulary, English vocabulary, working memory and short-term memory, and the balance between Dutch and English vocabulary. Small significant (α < .05) effects of bilingualism were found on onset phoneme identification and phoneme deletion, but post-hoc comparisons revealed no robust pairwise differences between the groups. Furthermore, effects of bilingualism sometimes disappeared when differences in language or memory skills were taken into account. Learning two languages simultaneously is not beneficial to – and importantly, also not detrimental to – phonological awareness.

Abstract

The aim of this study was to investigate whether early-English education benefits the perception
of English phonetic contrasts that are known to be perceptually confusable for Dutch
native speakers, comparing Dutch pupils who were enrolled in an early-English programme
at school from the age of four with pupils in a mainstream programme with English instruction
from the age of 11, and English-Dutch early bilingual children. Children were 4-5-yearolds
(start of primary school), 8-9-year-olds, or 11-12-year-olds (end of primary school).
Children were tested on four contrasts that varied in difficulty: /b/-/s/ (easy), /k/-/ɡ/ (intermediate),
/f/-/θ/ (difficult), /ε/-/æ/ (very difficult). Bilingual children outperformed the two other
groups on all contrasts except /b/-/s/. Early-English pupils did not outperform mainstream
pupils on any of the contrasts. This shows that early-English education as it is currently
implemented is not beneficial for pupils’ perception of non-native contrasts.

Abstract

This study investigated to what extent the Peabody Picture Vocabulary Test
(PPVT-4) is a reliable tool for measuring vocabulary knowledge of English as
a second language (L2), and to what extent L1 characteristics affect test
outcomes. The PPVT-4 was administered to Dutch pupils in six different
age groups (4-15 years old) who were or were not following an English
educational programme at school. Our first finding was that the PPVT-4
was not a reliable measure for pupils who were correct on maximally 24
items, but it was reliable for pupils who performed better. Second, both
primary-school and secondary-school pupils performed better on items
for which the phonological similarity between the English word and its
Dutch translation was higher. Third, young unexperienced L2 learners’
scores were predicted by Dutch lexical frequency, while older more
experienced pupils’ scores were predicted by English frequency. These
findings indicate that the PPVT may be inappropriate for use with L2
learners with limited L2 proficiency. Furthermore, comparisons of PPVT
scores across learners with different L1s are confounded by effects of L1
frequency and L1-L2 similarity. The PPVT-4 is however a suitable measure
to compare more proficient L2 learners who have the same L1.

Abstract

In recent years, the influence of alpha (7–13 Hz) phase on visual processing has received a lot of attention. Magneto‐/encephalography (M/EEG) studies showed that alpha phase indexes visual excitability and task performance. Studies with transcranial alternating current stimulation (tACS) aim to modulate oscillations and causally impact task performance. Here, we applied right occipital tACS (O2 location) to assess the functional role of alpha phase in a series of experiments. We presented visual stimuli at different pre‐determined, experimentally controlled, phases of the entraining tACS signal, hypothesizing that this should result in an oscillatory pattern of visual performance in specifically left hemifield detection tasks. In experiment 1, we applied 10 Hz tACS and used separate psychophysical staircases for six equidistant tACS‐phase conditions, obtaining contrast thresholds for detection of visual gratings in left or right hemifield. In experiments 2 and 3, tACS was at EEG‐based individual peak alpha frequency. In experiment 2, we measured detection rates for gratings with (pseudo‐)fixed contrast. In experiment 3, participants detected brief luminance changes in a custom‐built LED device, at eight equidistant alpha phases. In none of the experiments did the primary outcome measure over phase conditions consistently reflect a one‐cycle sinusoid. However, post hoc analyses of reaction times (RT) suggested that tACS alpha phase did modulate RT for specifically left hemifield targets in both experiments 1 and 2 (not measured in experiment 3). This observation requires future confirmation, but is in line with the idea that alpha phase causally gates visual inputs through cortical excitability modulation.

Abstract

The cerebral cortex underlies our complex cognitive capabilities, yet little is known about the specific genetic loci that influence human cortical structure. To identify genetic variants that affect cortical structure, we conducted a genome-wide association meta-analysis of brain magnetic resonance imaging data from 51,665 individuals. We analyzed the surface area and average thickness of the whole cortex and 34 regions with known functional specializations. We identified 199 significant loci and found significant enrichment for loci influencing total surface area within regulatory elements that are active during prenatal cortical development, supporting the radial unit hypothesis. Loci that affect regional surface area cluster near genes in Wnt signaling pathways, which influence progenitor expansion and areal identity. Variation in cortical structure is genetically correlated with cognitive function, Parkinson’s disease, insomnia, depression, neuroticism, and attention deficit hyperactivity disorder.

Abstract

Languages, like molecules, document evolutionary history. Darwin(1) observed that evolutionary change in languages greatly resembled the processes of biological evolution: inheritance from a common ancestor and convergent evolution operate in both. Despite many suggestions(2-4), few attempts have been made to apply the phylogenetic methods used in biology to linguistic data. Here we report a parsimony analysis of a large language data set. We use this analysis to test competing hypotheses - the "express-train''(5) and the "entangled-bank''(6,7) models - for the colonization of the Pacific by Austronesian-speaking peoples. The parsimony analysis of a matrix of 77 Austronesian languages with 5,185 lexical items produced a single most-parsimonious tree. The express-train model was converted into an ordered geographical character and mapped onto the language tree. We found that the topology of the language tree was highly compatible with the express-train model.

Abstract

This theme issue assembles current studies that ask how and why precise synchronization and related forms of rhythm interaction are expressed in a wide range of behaviour. The studies cover human activity, with an emphasis on music, and social behaviour, reproduction and communication in non-human animals. In most cases, the temporally aligned rhythms have short—from several seconds down to a fraction of a second—periods and are regulated by central nervous system pacemakers, but interactions involving rhythms that are 24 h or longer and originate in biological clocks also occur. Across this spectrum of activities, species and time scales, empirical work and modelling suggest that synchrony arises from a limited number of coupled-oscillator mechanisms with which individuals mutually entrain. Phylogenetic distribution of these common mechanisms points towards convergent evolution. Studies of animal communication indicate that many synchronous interactions between the signals of neighbouring individuals are specifically favoured by selection. However, synchronous displays are often emergent properties of entrainment between signalling individuals, and in some situations, the very signallers who produce a display might not gain any benefit from the collective timing of their production.

Abstract

What are the origins of musical rhythm? One approach to the biology and evolution of music consists in finding common musical traits across species. These similarities allow biomusicologists to infer when and how musical traits appeared in our species1
. A parallel approach to the biology and evolution of music focuses on finding statistical universals in human music2
. These include rhythmic features that appear above chance across musical cultures. One such universal is the production of categorical rhythms3
, defined as those where temporal intervals between note onsets are distributed categorically rather than uniformly2
,4
,5
. Prominent rhythm categories include those with intervals related by small integer ratios, such as 1:1 (isochrony) and 1:2, which translates as some notes being twice as long as their adjacent ones. In humans, universals are often defined in relation to the beat, a top-down cognitive process of inferring a temporal regularity from a complex musical scene1
. Without assuming the presence of the beat in other animals, one can still investigate its downstream products, namely rhythmic categories with small integer ratios detected in recorded signals. Here we combine the comparative and statistical universals approaches, testing the hypothesis that rhythmic categories and small integer ratios should appear in species showing coordinated group singing3
. We find that a lemur species displays, in its coordinated songs, the isochronous and 1:2 rhythm categories seen in human music, showing that such categories are not, among mammals, unique to humans3

Abstract

The discussion on root infinitives has mainly centered around their supposed modal usage. This article aims at modelling the form-function relation of the root infinitive phenomenon by taking into account the full range of interpretational facets encountered cross-linguistically and interindividually. Following the idea of a subsequent ‘‘cell partitioning’’ in the emergence of form-function correlations, I claim that it is the major fission between [+-finite] which is central to express temporal reference different from the default here&now in tense-oriented languages. In aspectual-oriented languages, a similar opposition is mastered with the marking of early aspectual forms. It is observed that in tense-oriented languages like Dutch and German, the progression of functions associated with the infinitival form proceeds from nonmodal to modal, whereas the reverse progression holds for the Russian infinitive. Based on this crucial observation, a model of acquisition is proposed which allows for a flexible and systematic relationship between morphological forms and their respective interpretational biases dependent on their developmental context. As for early child language, I argue that children entertain only two temporal parameters: one parameter is fixed to the here&now point in time, and a second parameter relates to the time talked about, the topic time; this latter time overlaps the situation time as long as no empirical evidence exists to support the emergence of a proper distinction between tense and aspect.

Abstract

To study the time course of sentence formulation, we monitored the eye movements of speakers as they described simple events. The similarity between speakers' initial eye movements and those of observers performing a nonverbal event-comprehension task suggested that response-relevant information was rapidly extracted from scenes, allowing speakers to select grammatical subjects based on comprehended events rather than salience. When speaking extemporaneously, speakers began fixating pictured elements less than a second before naming them within their descriptions, a finding consistent with incremental lexical encoding. Eye movements anticipated the order of mention despite changes in picture orientation, in who-did-what-to-whom, and in sentence structure. The results support Wundt's theory of sentence production.

Abstract

The central topic of this study is to investigate three- and four-place predicate in Yaqui, which are characterized by having multiple object arguments. As with other Southern Uto-Aztecan languages, it has been said that Yaqui follows the Primary/Secondary Object pattern (Dryer 1986). Actually, Yaqui presents three patterns: verbs like nenka ‘sell’ follow the direct–indirect object pattern, verbs like miika ‘give’ follow the primary object pattern, and verbs like chijakta ‘sprinkle’ follow the locative alternation pattern; the primary object pattern is the exclusive one found with derived verbs. This paper shows that the contrast between direct object and primary object languages is not absolute but rather one of degree, and hence two “object” selection principles are needed to explain this mixed system. The two principles are not limited to Yaqui but are found in other languages as well, including English.

Abstract

Psychology endeavors to develop theories of human capacities and behaviors on the basis of a variety of methodologies and dependent measures. We argue that one of the most divisive factors in psychological science is whether researchers choose to use computational modeling of theories (over and above data) during the scientific-inference process. Modeling is undervalued yet holds promise for advancing psychological science. The inherent demands of computational modeling guide us toward better science by forcing us to conceptually analyze, specify, and formalize intuitions that otherwise remain unexamined—what we dub open theory. Constraining our inference process through modeling enables us to build explanatory and predictive theories. Here, we present scientific inference in psychology as a path function in which each step shapes the next. Computational modeling can constrain these steps, thus advancing scientific inference over and above the stewardship of experimental practice (e.g., preregistration). If psychology continues to eschew computational modeling, we predict more replicability crises and persistent failure at coherent theory building. This is because without formal modeling we lack open and transparent theorizing. We also explain how to formalize, specify, and implement a computational model, emphasizing that the advantages of modeling can be achieved by anyone with benefit to all.

Abstract

A key strength of connectionist modelling is its ability to simulate both intact cognition and the behavioural effects of neural damage. We survey the literature, showing that models have been damaged in a variety of ways, e.g. by removing connections, by adding noise to connection weights, by scaling weights, by removing units and by adding noise to unit activations. While these different implementations of damage have often been assumed to be behaviourally equivalent, some theorists have made aetiological claims that rest on nonequivalence. They suggest that related deficits with different aetiologies might be accounted for by different forms of damage within a single model. We present two case studies that explore the effects of different forms of damage in two influential connectionist models, each of which has been applied to explain neuropsychological deficits. Our results indicate that the effect of simulated damage can indeed be sensitive to the way in which damage is implemented, particularly when the environment comprises subsets of items that differ in their statistical properties, but such effects are sensitive to relatively subtle aspects of the model’s training environment. We argue that, as a consequence, substantial methodological care is required if aetiological claims about simulated neural damage are to be justified, and conclude more generally that implementation assumptions, including those concerning simulated damage, must be fully explored when evaluating models of neurological deficits, both to avoid over-extending the explanatory power of specific implementations and to ensure that reported results are replicable.

Abstract

Gestures are often regarded as the most typical compensatory device used by language learners in communicative trouble. Yet gestural solutions to communicative problems have rarely been studied within any theory of second language use. The work pre­sented in this volume aims to account for second language learners’ strategic use of speech-associated gestures by combining a process-oriented framework for communi­cation strategies with a cognitive theory of gesture. Two empirical studies are presented. The production study investigates Swedish lear­ners of French and French learners of Swedish and their use of strategic gestures. The results, which are based on analyses of both individual and group behaviour, contradict popular opinion as well as theoretical assumptions from both fields. Gestures are not primarily used to replace speech, nor are they chiefly mimetic. Instead, learners use gestures with speech, and although they do exploit mimetic gestures to solve lexical problems, they also use more abstract gestures to handle discourse-related difficulties and metalinguistic commentary. The influence of factors such as proficiency, task, culture, and strategic competence on gesture use is discussed, and the oral and gestural strategic modes are compared. In the evaluation study, native speakers’ assessments of learners’ gestures, and the potential effect of gestures on evaluations of proficiency are analysed and discussed in terms of individual communicative style. Compensatory gestures function at multiple communicative levels. This has implica­tions for theories of communication strategies, and an expansion of the existing frameworks is discussed taking both cognitive and interactive aspects into account.

Abstract

Three groups of monolingual listeners, with Standard Chinese, Dutch and Hungarian as their native language, judged pairs of trisyllabic stimuli which differed only in their itch pattern. The segmental structure of the stimuli was made up by the experimenters and presented to subjects as being taken from a little-known language spoken on a South Pacific island. Pitch patterns consisted of a single rise-fall located on or near the second syllable. By and large, listeners selected the stimulus with the higher peak, the later eak, and the higher end rise as the one that signalled a question, regardless of language group. The result is argued to reflect innate, non-linguistic knowledge of the meaning of pitch variation, notably Ohala’s Frequency Code. A significant difference between groups is explained as due to the influence of the mother tongue.

Abstract

What is the long‐term trajectory of semantic memory deficits in patients who have suffered structural brain damage? Memory is, per definition, a changing faculty. The traditional view is that after an initial recovery period, the mature human brain has little capacity to repair or reorganize. More recently, it has been suggested that the central nervous system may be more plastic with the ability to change in neural structure, connectivity, and function. The latter observations are, however, largely based on normal learning in healthy subjects. Here, we report a patient who suffered bilateral ventro‐medial damage after presumed herpes encephalitis in 1971. He was seen regularly in the eighties, and we recently had the opportunity to re‐assess his semantic memory deficits. On semantic category fluency, he showed a very clear category‐specific deficit performing better that control data on non‐living categories and significantly worse on living items. Recent testing showed that his impairments have remained unchanged for more than 40 years. We suggest cautiousness when extrapolating the concept of brain plasticity, as observed during normal learning, to plasticity in the context of structural brain damage.

Abstract

Rede uitgesproken op 12 mei 2000 bij de aanvaarding van het ambt van hoogleraar in de neuropsychologie aan de Faculteit Sociale Wetenschappen KUN.

Abstract

In this study, event-related brain potential ffects of speech processing are obtained and compared to similar effects in sentence reading. In two experiments sentences were presented that contained three different types of grammatical violations. In one experiment sentences were presented word by word at a rate of four words per second. The grammatical violations elicited a Syntactic Positive Shift (P600/SPS), 500 ms after the onset of the word that rendered the sentence ungrammatical. The P600/SPS consisted of two phases, an early phase with a relatively equal anterior-posterior distribution and a later phase with a strong posterior distribution. We interpret the first phase as an indication of structural integration complexity, and the second phase as an indication of failing parsing operations and/or an attempt at reanalysis. In the second experiment the same syntactic violations were presented in sentences spoken at a normal rate and with normal intonation. These violations elicited a P600/SPS with the same onset as was observed for the reading of these sentences. In addition two of the three violations showed a preceding frontal negativity, most clearly over the left hemisphere.

Abstract

In this study, event-related brain potential effects of speech processing are obtained and compared to similar effects insentence reading. In two experiments spoken sentences were presented with semantic violations in sentence-signal or mid-sentence positions. For these violations N400 effects were obtained that were very similar to N400 effects obtained in reading. However, the N400 effects in speech were preceded by an earlier negativity (N250). This negativity is not commonly observed with written input. The early effect is explained as a manifestation of a mismatch between the word forms expected on the basis of the context, and the actual cohort of activated word candidates that is generated on the basis of the speech signal.

Abstract

Although the sentences that we hear or read have meaning, this does not necessarily mean that they are also true. Relatively little is known about the critical brain structures for, and the relative time course of, establishing the meaning and truth of linguistic expressions. We present electroencephalogram data that show the rapid parallel integration of both semantic and world
knowledge during the interpretation of a sentence. Data from functional magnetic resonance imaging revealed that the left inferior prefrontal cortex is involved in the integration of both meaning and world knowledge. Finally, oscillatory brain responses indicate that the brain keeps a record of what makes a sentence hard to interpret.

Abstract

Rhyme perception is an important predictor for future literacy. Assessing rhyme
abilities, however, commonly requires children to make explicit rhyme judgements on
single words. Here we explored whether infants already implicitly process rhymes in
natural rhyming contexts (child songs) and whether this response correlates with later
vocabulary size. In a passive listening ERP study, 10.5 month-old Dutch infants were
exposed to rhyming and non-rhyming child songs. Two types of rhyme effects were
analysed: (1) ERPs elicited by the first rhyme occurring in each song (rhyme sensitivity)
and (2) ERPs elicited by rhymes repeating after the first rhyme in each song (rhyme
repetition). Only for the latter a tentative negativity for rhymes from 0 to 200 ms
after the onset of the rhyme word was found. This rhyme repetition effect correlated
with productive vocabulary at 18 months-old, but not with any other vocabulary
measure (perception at 10.5 or 18 months-old). While awaiting future replication, the
study indicates precursors of phonological awareness already during infancy and with
ecologically valid linguistic stimuli.

Abstract

Children’s songs are a great source for linguistic learning. Here we explore whether children can acquire novel words in a second language by playing a game featuring children’s songs in a playhouse. The playhouse is designed by the Noplica foundation (www.noplica.nl) to advance language learning through unsupervised play. We present data from three experiments that serve to scientifically proof the functionality of one game of the playhouse: the Energy Center. For this game, children move three hand-bikes mounted on a panel within the playhouse. Once the children cycle, a song starts playing that is accompanied by musical instruments. In our experiments, children executed a picture-selection task to evaluate whether they acquired new vocabulary from the songs presented during the game. Two of our experiments were run in the field, one at a Dutch and one at an Indian pre-school. The third experiment features data from a more controlled laboratory setting. Our results partly confirm that the Energy Center is a successful means to support vocabulary acquisition in a second language. More research with larger sample sizes and longer access to the Energy Center is needed to evaluate the overall functionality of the game. Based on informal observations at our test sites, however, we are certain that children do pick up linguistic content from the songs during play, as many of the children repeat words and phrases from the songs they heard. We will pick up upon these promising observations during future studies.

Abstract

Infants exploit acoustic boundaries to perceptually organize phrases in speech. This prosodic parsing ability is well‐attested and is a cornerstone to the development of speech perception and grammar. However, infants also receive linguistic input in child songs. This study provides evidence that infants parse songs into meaningful phrasal units and replicates previous research for speech. Six‐month‐old Dutch infants (n = 80) were tested in the song or speech modality in the head‐turn preference procedure. First, infants were familiarized to two versions of the same word sequence: One version represented a well‐formed unit, and the other contained a phrase boundary halfway through. At test, infants were presented two passages, each containing one version of the familiarized sequence. The results for speech replicated the previously observed preference for the passage containing the well‐formed sequence, but only in a more fine‐grained analysis. The preference for well‐formed phrases was also observed in the song modality, indicating that infants recognize phrase structure in song. There were acoustic differences between stimuli of the current and previous studies, suggesting that infants are flexible in their processing of boundary cues while also providing a possible explanation for differences in effect sizes.

Abstract

This paper investigates the time and space complexity of word order computation in the psycholinguistically motivated grammar formalism of Performance Grammar (PG). In PG, the first stage of syntax assembly yields an unordered tree ('mobile') consisting of a hierarchy of lexical frames (lexically anchored elementary trees). Associated with each lexica l frame is a linearizer—a Finite-State Automaton that locally computes the left-to-right order of the branches of the frame. Linearization takes place after the promotion component may have raised certain constituents (e.g. Wh- or focused phrases) into the domain of lexical frames higher up in the syntactic mobile. We show that the worst-case time and space complexity of analyzing input strings of length n is O(n5) and O(n4), respectively. This result compares favorably with the time complexity of word-order computations in Tree Adjoining Grammar (TAG). A comparison with Head-Driven Phrase Structure Grammar (HPSG) reveals that PG yields a more declarative linearization method, provided that the FSA is rewritten as an equivalent regular expression.

Abstract

Repetition appears to be part of error correction and action preparation in all domains that involve producing an action sequence. The present work contends that the ubiquity of repetition is due to its role in resolving a problem inherent to planning and retrieval of action sequences: the Problem of Retrieval. Repetitions occur when the production to perform next is not activated enough to be executed. Repetitions are helpful in this situation because the repeated action sequence activates the likely continuation. We model a corpus of natural speech using a recurrent network, with words as units of production. We show that repeated material makes upcoming words more predictable, especially when more than one word is repeated. Speakers are argued to produce multiword repetitions by using backward associations to reactivate recently produced words. The existence of multiword repetitions means that speakers must decide where to reinitiate execution from. We show that production restarts from words that have seldom occurred in a predictive preceding-word context and have often occurred utterance-initially. These results are explained by competition between preceding-context and top-down cues over the course of language learning. The proposed theory improves on structural accounts of repetition disfluencies, and integrates repetition disfluencies in language production with repetitions observed in other domains of skilled action.

Abstract

There is evidence that the process of executing a planned utterance involves the use of both preceding-context and top-down cues. Utterance-initial words are cued only by the top-down plan. In contrast, non-initial words are cued both by top-down cues and preceding-context cues. Co-existence of both cue types raises the question of how they interact during learning. We argue that this interaction is competitive: items that tend to be preceded by predictive preceding-context cues are harder to activate from the plan without this predictive context. A novel computational model of this competition is developed. The model is tested on a corpus of repetition disfluencies and shown to account for the influences on patterns of restarts during production. In particular, this model predicts a novel Initiation Effect: following an interruption, speakers re-initiate production from words that tend to occur in utterance-initial position, even when they are not initial in the interrupted utterance.

Abstract

Children with developmental language disorder (DLD) regularly use the base form of verbs (e.g., dance) instead of inflected forms (e.g., danced). We propose an account of this behavior in which children with DLD have difficulty processing novel inflected verbs in their input. This leads the inflected form to face stronger competition from alternatives. Competition is resolved by the production of a more accessible alternative with high semantic overlap with the inflected form: in English, the bare form. We test our account computationally by training a nonparametric Bayesian model that infers the productivity of the inflectional suffix (-ed). We systematically vary the number of novel types of inflected verbs in the input to simulate the input as processed by children with and without DLD. Modeling results are consistent with our hypothesis, suggesting that children’s inconsistent use of inflectional morphemes could stem from inferences they make on the basis of impoverished data.

Abstract

Humans are deeply affected by stories, yet it is unclear how. In this study, we explored two aspects of aesthetic experiences during narrative engagement - literariness and narrative fluctuations in appraised emotional intensity. Independent ratings of literariness and emotional intensity of two literary stories were used to predict blood-oxygen-level-dependent signal changes in 52 listeners from an existing fMRI dataset. Literariness was associated with increased activation in brain areas linked to semantic integration (left angular gyrus, supramarginal gyrus, and precuneus), and decreased activation in bilateral middle temporal cortices, associated with semantic representations and word memory. Emotional intensity correlated with decreased activation in a bilateral frontoparietal network that is often associated with controlled attention. Our results confirm a neural dissociation in processing literary form and emotional content in stories and generate new questions about the function of and interaction between attention, social cognition, and semantic systems during literary engagement and aesthetic experiences.

Abstract

The representations generated by many mod-
els of language (word embeddings, recurrent
neural networks and transformers) correlate
to brain activity recorded while people read.
However, these decoding results are usually
based on the brain’s reaction to syntactically
and semantically sound language stimuli. In
this study, we asked: how does an LSTM (long
short term memory) language model, trained
(by and large) on semantically and syntac-
tically intact language, represent a language
sample with degraded semantic or syntactic
information? Does the LSTM representation
still resemble the brain’s reaction? We found
that, even for some kinds of nonsensical lan-
guage, there is a statistically significant rela-
tionship between the brain’s activity and the
representations of an LSTM. This indicates
that, at least in some instances, LSTMs and the
human brain handle nonsensical data similarly.

Abstract

Preregistration, the act of specifying a research plan in advance, is becoming more common in scientific research. Infant researchers contend with unique problems that might make preregistration particularly challenging. Infants are a hard‐to‐reach population, usually yielding small sample sizes, they can only complete a limited number of trials, and they can be excluded based on hard‐to‐predict complications (e.g., parental interference, fussiness). In addition, as effects themselves potentially change with age and population, it is hard to calculate an a priori effect size. At the same time, these very factors make preregistration in infant studies a valuable tool. A priori examination of the planned study, including the hypotheses, sample size, and resulting statistical power, increases the credibility of single studies and adds value to the field. Preregistration might also improve explicit decision making to create better studies. We present an in‐depth discussion of the issues uniquely relevant to infant researchers, and ways to contend with them in preregistration and study planning. We provide recommendations to researchers interested in following current best practices.

Abstract

The endeavor to understand the human brain has seen more progress in the last few decades than in the previous two millennia. Still, our understanding of how the human brain relates to behavior in the real world and how this link is modulated by biological, social, and environmental factors is limited. To address this, we designed the Healthy Brain Study (HBS), an interdisciplinary, longitudinal, cohort study based on multidimensional, dynamic assessments in both the laboratory and the real world. Here, we describe the rationale and design of the currently ongoing HBS. The HBS is examining a population-based sample of 1,000 healthy participants (age 30-39) who are thoroughly studied across an entire year. Data are collected through cognitive, affective, behavioral, and physiological testing, neuroimaging, bio-sampling, questionnaires, ecological momentary assessment, and real-world assessments using wearable devices. These data will become an accessible resource for the scientific community enabling the next step in understanding the human brain and how it dynamically and individually operates in its bio-social context. An access procedure to the collected data and bio-samples is in place and published on https://www.healthybrainstudy.nl/en/data-and-methods.

https://www.trialregister.nl/trial/7955

Abstract

Second language (L2) learners frequently encounter persistent difficulty in perceiving certain non-native sound contrasts, i.e., a phenomenon called “phonological deafness”. However, if extensive L2 experience leads to neuroplastic changes in the phonological system, then the capacity to discriminate non-native phonemic contrasts should progressively improve. Such perceptual changes should be attested by modifications at the neurophysiological level. We designed an EEG experiment in which the listeners’ perceptual capacities to discriminate second language phonemic contrasts influence the processing of lexical-semantic violations. Semantic congruency of critical words in a sentence context was driven by a phonemic contrast that was unique to the L2, English (e.g.,/ɪ/-/i:/, ship – sheep). Twenty-eight young adult native speakers of French with intermediate proficiency in English listened to sentences that contained either a semantically congruent or incongruent critical word (e.g., The anchor of the ship/*sheep was let down) while EEG was recorded. Three ERP effects were found to relate to increasing L2 proficiency: (1) a left frontal auditory N100 effect, (2) a smaller fronto-central phonological mismatch negativity (PMN) effect and (3) a semantic N400 effect. No effect of proficiency was found on oscillatory markers. The current findings suggest that neuronal plasticity in the human brain allows for the late acquisition of even hard-wired linguistic features such as the discrimination of phonemic contrasts in a second language. This is the first time that behavioral and neurophysiological evidence for the critical role of neural plasticity underlying L2 phonological processing and its interdependence with semantic processing has been provided. Our data strongly support the idea that pieces of information from different levels of linguistic processing (e.g., phonological, semantic) strongly interact and influence each other during online language processing.

Abstract

The present article on executive control addresses the issue of the locus of the Stroop effect by examining neurophysiological components marking conflict monitoring, interference suppression, and conflict resolution. Our goal was to provide an overview of a series of determining neurophysiological findings including neural source reconstruction data on distinct executive control processes and sub-processes involved in the Stroop task. Consistently, a fronto-central N2 component is found to reflect conflict monitoring processes, with its main neural generator being the anterior cingulate cortex (ACC). Then, for cognitive control tasks that involve a linguistic component like the Stroop task, the N2 is followed by a centro-posterior N400 and subsequently a late sustained potential (LSP). The N400 is mainly generated by the ACC and the prefrontal cortex (PFC) and is thought to reflect interference suppression, whereas the LSP plausibly reflects conflict resolution processes. The present overview shows that ERP constitute a reliable methodological tool for tracing with precision the time course of different executive processes and sub-processes involved in experimental tasks involving a cognitive conflict. Future research should shed light on the fine-grained mechanisms of control respectively involved in linguistic and non-linguistic tasks.

Abstract

Speakers and listeners usually interact in larger discourses than single words or even single sentences. The goal of the present study was to identify the neural bases reflecting how the mental representation of the situation denoted in a multi-sentence discourse (situation model) is constructed and shared between speakers and listeners. An fMRI study using a variant of the ambiguous text paradigm was designed. Speakers (n=15) produced ambiguous texts in the scanner and listeners (n=27) subsequently listened to these texts in different states of ambiguity: preceded by a highly informative, intermediately informative or no title at all. Conventional BOLD activation analyses in listeners, as well as inter-subject correlation analyses between the speakers’ and the listeners’ hemodynamic time courses were performed. Critically, only the processing of disambiguated, coherent discourse with an intelligible situation model representation involved (shared) activation in bilateral lateral parietal and medial prefrontal regions. This shared spatiotemporal pattern of brain activation between the speaker and the listener suggests that the process of memory retrieval in medial prefrontal regions and the binding of retrieved information in the lateral parietal cortex constitutes a core mechanism underlying the communication of complex conceptual representations.