Publications

Abstract

Like many other types of memory formation, novel word learning benefits from an offline consolidation period after the initial encoding phase. A previous EEG study has shown that retrieval of novel words elicited more word-like-induced electrophysiological brain activity in the theta band after consolidation [Bakker, I., Takashima, A., van Hell, J. G., Janzen, G., & McQueen, J. M. Changes in theta and beta oscillations as signatures of novel word consolidation. Journal of Cognitive Neuroscience, 27, 1286–1297, 2015]. This suggests that theta-band oscillations play a role in lexicalization, but it has not been demonstrated that this effect is directly caused by the formation of lexical representations. This study used magnetoencephalography to localize the theta consolidation effect to the left posterior middle temporal gyrus (pMTG), a region known to be involved in lexical storage. Both untrained novel words and words learned immediately before test elicited lower theta power during retrieval than existing words in this region. After a 24-hr consolidation period, the difference between novel and existing words decreased significantly, most strongly in the left pMTG. The magnitude of the decrease after consolidation correlated with an increase in behavioral competition effects between novel words and existing words with similar spelling, reflecting functional integration into the mental lexicon. These results thus provide new evidence that consolidation aids the development of lexical representations mediated by the left pMTG. Theta synchronization may enable lexical access by facilitating the simultaneous activation of distributed semantic, phonological, and orthographic representations that are bound together in the pMTG.

Abstract

Memory reprocessing following acquisition enhances memory consolidation. Specifically, neural activity during encoding is thought to be ‘replayed’ during subsequent slow-wave sleep. Such memory replay is thought to contribute to the functional reorganization of neural memory traces. In particular, memory replay may facilitate the exchange of information across brain regions by inducing a reconfiguration of connectivity across the brain. Memory reactivation can be induced by external cues through a procedure known as “targeted memory reactivation”. Here, we analysed data from a published study with auditory cues used to reactivate visual object-location memories during slow-wave sleep. We characterized effects of memory reactivation on brain network connectivity using graph-theory. We found that cue presentation during slow-wave sleep increased global network integration of occipital cortex, a visual region that was also active during retrieval of object locations. Although cueing did not have an overall beneficial effect on the retention of cued versus uncued associations, individual differences in overnight memory stabilization were related to enhanced network integration of occipital cortex. Furthermore, occipital cortex displayed enhanced connectivity with mnemonic regions, namely the hippocampus, parahippocampal gyrus, thalamus and medial prefrontal cortex during cue sound presentation. Together, these results suggest a neural mechanism where cue-induced replay during sleep increases integration of task-relevant perceptual regions with mnemonic regions. This cross-regional integration may be instrumental for the consolidation and long-term storage of enduring memories.

Abstract

The neural mechanism for selectively tuning in to a target speaker while tuning out the others in a multi-speaker situation (i.e., the cocktail-party effect) remains elusive. Here we addressed this issue by measuring brain activity simultaneously from a listener and from multiple speakers while they were involved in naturalistic conversations. Results consistently show selectively enhanced interpersonal neural synchronization (INS) between the listener and the attended speaker at left temporal–parietal junction, compared with that between the listener and the unattended speaker across different multi-speaker situations. Moreover, INS increases significantly prior to the occurrence of verbal responses, and even when the listener’s brain activity precedes that of the speaker. The INS increase is independent of brain-to-speech synchronization in both the anatomical location and frequency range. These findings suggest that INS underlies the selective process in a multi-speaker situation through neural predictions at the content level but not the sensory level of speech.

Abstract

In this article we investigate the relation between discourse markers and turn-transition strategies in face-to-face conversations and Instant Messaging (IM), that is, unplanned, real-time, text-based, computer-mediated communication. By means of a quantitative corpus study of utterances containing a discourse marker, we show that utterance-final discourse markers are used more often in IM than in face-to-face conversations. Moreover, utterance-final discourse markers are shown to occur more often at points of turn-transition compared with points of turn-maintenance in both types of conversation. From our results we conclude that the discourse markers in utterance-final position can function as a turn-transition mechanism, signaling that the turn is over and the floor is open to the hearer. We argue that this linguistic turn-taking strategy is essentially similar in face-to-face and IM communication. Our results add to the evidence that communication in IM is more like speech than like writing.

Abstract

Biologically inspired spiking networks are an important tool to study the nature of computation and cognition in neural systems. In this work, we investigate the representational capacity of spiking networks engaged in an identity mapping task. We compare two schemes for encoding symbolic input, one in which input is injected as a direct current and one where input is delivered as a spatio-temporal spike pattern. We test the ability of networks to discriminate their input as a function of the number of distinct input symbols. We also compare performance using either membrane potentials or filtered spike trains as state variable. Furthermore, we investigate how the circuit behavior depends on the balance between excitation and inhibition, and the degree of synchrony and regularity in its internal dynamics. Finally, we compare different linear methods of decoding population activity onto desired target labels. Overall, our results suggest that even this simple mapping task is strongly influenced by design choices on input encoding, state-variables, circuit characteristics and decoding methods, and these factors can interact in complex ways. This work highlights the importance of constraining computational network models of behavior by available neurobiological evidence.

Abstract

While the importance of mental simulation during literary reading has long been recognized, we know little about the factors that determine when, what, and how much readers mentally simulate. Here we investigate the influence of a specific text characteristic, namely verb tense (present vs. past), on mental simulation during literary reading. Verbs usually denote the actions and events that take place in narratives and hence it is hypothesized that verb tense will influence the amount of mental simulation elicited in readers. Although the present tense is traditionally considered to be more “vivid”, this study is one of the first to experimentally assess this claim. We recorded eye-movements while subjects read stories in the past or present tense and collected data regarding self-reported levels of mental simulation, transportation and appreciation. We found no influence of tense on any of the offline measures. The eye-tracking data showed a slightly more complex pattern. Although we did not find a main effect of sensorimotor simulation content on reading times, we were able to link the degree to which subjects slowed down when reading simulation eliciting content to offline measures of attention and transportation, but this effect did not interact with the tense of the story. Unexpectedly, we found a main effect of tense on reading times per word, with past tense stories eliciting longer first fixation durations and gaze durations. However, we were unable to link this effect to any of the offline measures. In sum, this study suggests that tense does not play a substantial role in the process of mental simulation elicited by literary stories.

Abstract

Predictive language processing is often studied by measuring eye movements as participants look at objects on a computer screen while they listen to spoken sentences. The use of this variant of the visual world paradigm has shown that information encountered by a listener at a spoken verb can give rise to anticipatory eye movements to a target object, which is taken to indicate that people predict upcoming words. The ecological validity of such findings remains questionable, however, because these computer experiments used two-dimensional (2D) stimuli that are mere abstractions of real world objects. Here we present a visual world paradigm study in a three-dimensional (3D) immersive virtual reality environment. Despite significant changes in the stimulus material and the different mode of stimulus presentation, language-mediated anticipatory eye movements were observed. These findings thus indicate prediction of upcoming words in language comprehension in a more naturalistic setting where natural depth cues are preserved. Moreover, the results confirm the feasibility of using eye-tracking in rich and multimodal 3D virtual environments.

Abstract

One of the fundamental issues for a language is its capacity to express
argument structure unambiguously. This study presents evidence
for the emergence and the incremental development of these
basic mechanisms in a newly developing language, Central Taurus
Sign Language. Our analyses identify universal patterns in both the
emergence and development of these mechanisms and in languagespecific
trajectories.

Abstract

The aim of the present fMRI study was to investigate whether typical and dyslexic adult readers differed in the neural correlates of audiovisual speech processing. We tested for Blood Oxygen-Level Dependent (BOLD) activity differences between these two groups in a 1-back task, as they processed written (word, illegal consonant strings) and spoken (auditory, visual and audiovisual) stimuli. When processing written stimuli, dyslexic readers showed reduced activity in the supramarginal gyrus, a region suggested to play an important role in phonological processing, but only when they processed strings of consonants, not when they read words. During the speech perception tasks, dyslexic readers were only slower than typical readers in their behavioral responses in the visual speech condition. Additionally, dyslexic readers presented reduced neural activation in the auditory, the visual, and the audiovisual speech conditions. The groups also differed in terms of superadditivity, with dyslexic readers showing decreased neural activation in the regions of interest. An additional analysis focusing on vision-related processing during the audiovisual condition showed diminished activation for the dyslexic readers in a fusiform gyrus cluster. Our results thus suggest that there are differences in audiovisual speech processing between dyslexic and normal readers. These differences might be explained by difficulties in processing the unisensory components of audiovisual speech, more specifically, dyslexic readers may benefit less from visual information during audiovisual speech processing than typical readers. Given that visual speech processing supports the development of phonological skills fundamental in reading, differences in processing of visual speech could contribute to differences in reading ability between typical and dyslexic readers.

Abstract

Speaking and listening are complex tasks that we perform on a daily basis, almost without conscious effort. Interestingly, speaking almost never occurs without listening: whenever we speak, we at least hear our own speech. The research in this thesis is concerned with how the perception of our own speech influences our speaking behavior. We show that unconsciously, we actively monitor this auditory feedback of our own speech. This way, we can efficiently take action and adapt articulation when an error occurs and auditory feedback does not correspond to our expectation. Processing the auditory feedback of our speech does not, however, automatically affect speech production. It is subject to a number of constraints. For example, we do not just track auditory feedback, but also its consistency. If auditory feedback is more consistent over time, it has a stronger influence on speech production. In addition, we investigated how auditory feedback during speech is processed in the brain, using magnetoencephalography (MEG). The results suggest the involvement of a broad cortical network including both auditory and motor-related regions. This is consistent with the view that the auditory center of the brain is involved in comparing auditory feedback to our expectation of auditory feedback. If this comparison yields a mismatch, motor-related regions of the brain can be recruited to alter the ongoing articulations.

Abstract

When talking, speakers continuously monitor and use the auditory feedback of their own voice to control and inform speech production processes. When speakers are provided with auditory feedback that is perturbed in real time, most of them compensate for this by opposing the feedback perturbation. But some speakers follow the perturbation. In the current study, we investigated whether the state of the speech production system at perturbation onset may determine what type of response (opposing or following) is given. The results suggest that whether a perturbation-related response is opposing or following depends on ongoing fluctuations of the production system: It initially responds by doing the opposite of what it was doing. This effect and the non-trivial proportion of following responses suggest that current production models are inadequate: They need to account for why responses to unexpected sensory feedback depend on the production-system’s state at the time of perturbation.

Abstract

Speaking is a complex motor skill which requires near instantaneous integration of sensory and motor-related information. Current theory hypothesizes a complex interplay between motor and auditory processes during speech production, involving the online comparison of the speech output with an internally generated forward model. To examine the neural correlates of this intricate interplay between sensory and motor processes, the current study uses altered auditory feedback (AAF) in combination with magnetoencephalography (MEG). Participants vocalized the vowel/e/and heard auditory feedback that was temporarily pitch-shifted by only 25 cents, while neural activity was recorded with MEG. As a control condition, participants also heard the recordings of the same auditory feedback that they heard in the first half of the experiment, now without vocalizing. The participants were not aware of any perturbation of the auditory feedback. We found auditory cortical areas responded more strongly to the pitch shifts during vocalization. In addition, auditory feedback perturbation resulted in spectral power increases in the θ and lower β bands, predominantly in sensorimotor areas. These results are in line with current models of speech production, suggesting auditory cortical areas are involved in an active comparison between a forward model's prediction and the actual sensory input. Subsequently, these areas interact with motor areas to generate a motor response. Furthermore, the results suggest that θ and β power increases support auditory-motor interaction, motor error detection and/or sensory prediction processing.

Abstract

Children’s songs often contain rhyming words at phrase endings. In this study, we investigated whether infants can already recognize this phonological pattern in songs. Earlier studies using lists of spoken words were equivocal on infants’ spontaneous processing of rhymes (Hayes, Slater, & Brown, 2000; Jusczyk, Goodman, & Baumann, 1999). Songs, however, constitute an ecologically valid rhyming stimulus, which could allow for spontaneous processing of this phonological pattern in infants. Novel children’s songs with rhyming and non-rhyming lyrics using pseudo-words were presented to 35 9-month-old Dutch infants using the Headturn Preference Procedure. Infants on average listened longer to the non-rhyming songs, with around half of the infants however exhibiting a preference for the rhyming songs. These results highlight that infants have the processing abilities to benefit from their natural rhyming input for the development of their phonological abilities.

Abstract

Recent decades have ushered in tremendous progress in understanding the neural basis of language. Most of our current knowledge on language and the brain, however, is derived from lab-based experiments that are far removed from everyday language use, and that are inspired by questions originating in linguistic and psycholinguistic contexts. In this paper we argue that in order to make progress, the field needs to shift its focus to understanding the neurobiology of naturalistic language comprehension. We present here a new conceptual framework for understanding the neurobiological organization of language comprehension. This framework is non-language-centered in the computational/neurobiological constructs it identifies, and focuses strongly on context. Our core arguments address three general issues: (i) the difficulty in extending language-centric explanations to discourse; (ii) the necessity of taking context as a serious topic of study, modeling it formally and acknowledging the limitations on external validity when studying language comprehension outside context; and (iii) the tenuous status of the language network as an explanatory construct. We argue that adopting this framework means that neurobiological studies of language will be less focused on identifying correlations between brain activity patterns and mechanisms postulated by psycholinguistic theories. Instead, they will be less self-referential and increasingly more inclined towards integration of language with other cognitive systems, ultimately doing more justice to the neurobiological organization of language and how it supports language as it is used in everyday life.

Abstract

The multilingual brain implements mechanisms that serve to select the appropriate language as a function of the communicative environment. Engaging these mechanisms on a regular basis appears to have consequences for brain structure and function. Studies have implicated the caudate nuclei as important nodes in polyglot language control processes, and have also shown structural differences in the caudate nuclei in bilingual compared to monolingual populations. However, the majority of published work has focused on the categorical differences between monolingual and bilingual individuals, and little is known about whether these findings extend to multilingual individuals, who have even greater language control demands. In the present paper, we present an analysis of the volume and morphology of the caudate nuclei, putamen, pallidum and thalami in 75 multilingual individuals who speak three or more languages. Volumetric analyses revealed a significant relationship between multilingual experience and right caudate volume, as well as a marginally significant relationship with left caudate volume. Vertex-wise analyses revealed a significant enlargement of dorsal and anterior portions of the left caudate nucleus, known to have connectivity with executive brain regions, as a function of multilingual expertise. These results suggest that multilingual expertise might exercise a continuous impact on brain structure, and that as additional languages beyond a second are acquired, the additional demands for linguistic and cognitive control result in modifications to brain structures associated with language management processes.

Abstract

A commentary on
Broca Pars Triangularis Constitutes a “Hub” of the Language-Control Network during Simultaneous Language Translation

by Elmer, S. (2016). Front. Hum. Neurosci. 10:491. doi: 10.3389/fnhum.2016.00491

Elmer (2016) conducted an fMRI investigation of “simultaneous language translation” in five participants. The article presents group and individual analyses of German-to-Italian and Italian-to-German translation, confined to a small set of anatomical regions previously reported to be involved in multilingual control. Here we take the opportunity to discuss concerns regarding certain aspects of the study.

Abstract

Participants’ performance differs when conducting a task in the presence of a secondary individual, moreover the opinion the participant has of this individual also plays a role. Using EEG, we investigated how previous interactions with, and evaluations of, an avatar in virtual reality subsequently influenced attentional allocation to the face of that avatar. We focused on changes in the alpha activity as an index of attentional allocation. We found that the onset of an avatar’s face whom the participant had developed a rapport with induced greater alpha suppression. This suggests greater attentional resources are allocated to the interacted-with avatars. The evaluative ratings of the avatar induced a U-shaped change in alpha suppression, such that participants paid most attention when the avatar was rated as average. These results suggest that attentional allocation is an important element of how behaviour is altered in the presence of a secondary individual and is modulated by our opinion of that individual.

Abstract

The cause of developmental dyslexia is still unknown despite decades of intense research. Many causal explanations have been proposed, based on the range of impairments displayed by affected individuals. Here we draw attention to the fact that many of these impairments are also shown by illiterate individuals who have not received any or very little reading instruction. We suggest that this fact may not be coincidental and that the performance differences of both illiterates and individuals with dyslexia compared to literate controls are, to a substantial extent, secondary consequences of either reduced or suboptimal reading experience or a combination of both. The search for the primary causes of reading impairments will make progress if the consequences of quantitative and qualitative differences in reading experience are better taken into account and not mistaken for the causes of reading disorders. We close by providing four recommendations for future research.

Abstract

This study investigates the implicit sequence learning abilities of dyslexic children using an artificial grammar learning task with an extended exposure period. Twenty children with developmental dyslexia participated in the study and were matched with two control groups—one matched for age and other for reading skills. During 3 days, all participants performed an acquisition task, where they were exposed to colored geometrical forms sequences with an underlying grammatical structure. On the last day, after the acquisition task, participants were tested in a grammaticality classification task. Implicit sequence learning was present in dyslexic children, as well as in both control groups, and no differences between groups were observed. These results suggest that implicit learning deficits per se cannot explain the characteristic reading difficulties of the dyslexics.

Abstract

Fiction is vital to our being. Many people enjoy engaging with fiction every day. Here we focus on literary reading as 1 instance of fiction consumption from a cognitive neuroscience perspective. The brain processes which play a role in the mental construction of fiction worlds and the related engagement with fictional characters, remain largely unknown. The authors discuss the neurocognitive poetics model (Jacobs, 2015a) of literary reading specifying the likely neuronal correlates of several key processes in literary reading, namely inference and situation model building, immersion, mental simulation and imagery, figurative language and style, and the issue of distinguishing fact from fiction. An overview of recent work on these key processes is followed by a discussion of methodological challenges in studying the brain bases of fiction processing

Abstract

Low-frequency neural entrainment to rhythmic input
has been hypothesized as a canonical mechanism
that shapes sensory perception in time. Neural
entrainment is deemed particularly relevant for
speech analysis, as it would contribute to the extraction
of discrete linguistic elements from continuous
acoustic signals. However, its causal influence in
speech perception has been difficult to establish.
Here, we provide evidence that oscillations build temporal
predictions about the duration of speech tokens
that affect perception. Using magnetoencephalography
(MEG), we studied neural dynamics during
listening to sentences that changed in speech rate.
Weobserved neural entrainment to preceding speech
rhythms persisting for several cycles after the change
in rate. The sustained entrainment was associated
with changes in the perceived duration of the last
word’s vowel, resulting in the perception of words
with different meanings. These findings support oscillatory
models of speech processing, suggesting that
neural oscillations actively shape speech perception.

Abstract

Neural oscillations may be instrumental for the tracking and segmentation of continuous speech. Earlier work has suggested that delta, theta and gamma oscillations entrain to the speech rhythm. We used magnetoencephalography and a large sample of 102 participants to investigate oscillatory entrainment to speech, and observed robust entrainment of delta and theta activity, and weak group-level gamma entrainment. We show that the peak frequency and the hemispheric lateralisation of the entrainment are subject to considerable individual variability. The first finding may support the involvement of intrinsic oscillations in entrainment, and the second finding suggests that there is no systematic default right-hemispheric bias for processing acoustic signals on a slow time scale. Although low frequency entrainment to speech is a robust phenomenon, the characteristics of entrainment vary across individuals, and this variation is important for understanding the underlying neural mechanisms of entrainment, as well as its functional significance.

Abstract

Reinstatement of memory-related neural activity measured with high temporal precision potentially provides a useful index for real-time monitoring of the timing of activation of memory content during cognitive processing. The utility of such an index extends to any situation where one is interested in the (relative) timing of activation of different sources of information in memory, a paradigm case of which is tracking lexical activation during language processing. Essential for this approach is that memory reinstatement effects are robust, so that their absence (in the average) definitively indicates that no lexical activation is present. We used electroencephalography to test the robustness of a reported subsequent memory finding involving reinstatement of frequency-specific entrained oscillatory brain activity during subsequent recognition. Participants learned lists of words presented on a background flickering at either 6 or 15 Hz to entrain a steady-state brain response. Target words subsequently presented on a non-flickering background that were correctly identified as previously seen exhibited reinstatement effects at both entrainment frequencies. Reliability of these statistical inferences was however critically dependent on the approach used for multiple comparisons correction. We conclude that effects are not robust enough to be used as a reliable index of lexical activation during language processing.

Abstract

We present the Narrative Brain Dataset, an fMRI dataset that was collected during spoken presentation of short excerpts of three
stories in Dutch. Together with the brain imaging data, the dataset contains the written versions of the stimulation texts. The texts are
accompanied with stochastic (perplexity and entropy) and semantic computational linguistic measures. The richness and unconstrained
nature of the data allows the study of language processing in the brain in a more naturalistic setting than is common for fMRI studies.
We hope that by making NBD available we serve the double purpose of providing useful neural data to researchers interested in natural
language processing in the brain and to further stimulate data sharing in the field of neuroscience of language.

Abstract

Prior knowledge about the visual world can change how a visual stimulus is processed. Two forms of prior knowledge are often distinguished: stimulus familiarity (i.e., whether a stimulus has been seen before) and stimulus expectation (i.e., whether a stimulus is expected to occur, based on the context). Neurophysiological studies in monkeys have shown suppression of spiking activity both for expected and for familiar items in object-selective inferotemporal cortex. It is an open question, however, if and how these types of knowledge interact in their modulatory effects on the sensory response. To address this issue and to examine whether previous findings generalize to noninvasively measured neural activity in humans, we separately manipulated stimulus familiarity and expectation while noninvasively recording human brain activity using magnetoencephalography. We observed independent suppression of neural activity by familiarity and expectation, specifically in the lateral occipital complex, the putative human homologue of monkey inferotemporal cortex. Familiarity also led to sharpened response dynamics, which was predominantly observed in early visual cortex. Together, these results show that distinct types of sensory knowledge jointly determine the amount of neural resources dedicated to object processing in the visual ventral stream.

Abstract

As conversation is the most important way of using language, linguists and psychologists should combine forces to investigate how interlocutors deal with the cognitive demands arising during conversation. Linguistic analyses of corpora of conversation are needed to understand the structure of conversations, and experimental work is indispensable for understanding the underlying cognitive processes. We argue that joint consideration of corpus and experimental data is most informative when the utterances elicited in a lab experiment match those extracted from a corpus in relevant ways. This requirement to compare like with like seems obvious but is not trivial to achieve. To illustrate this approach, we report two experiments where responses to polar (yes/no) questions were elicited in the lab and the response latencies were compared to gaps between polar questions and answers in a corpus of conversational speech. We found, as expected, that responses were given faster when they were easy to plan and planning could be initiated earlier than when they were harder to plan and planning was initiated later. Overall, in all but one condition, the latencies were longer than one would expect based on the analyses of corpus data. We discuss the implication of this partial match between the data sets and more generally how corpus and experimental data can best be combined in studies of conversation.

Abstract

Do people routinely pre-activate the meaning and even the phonological form of upcoming words? The most acclaimed evidence for phonological prediction comes from a 2005 Nature Neuroscience publication by DeLong, Urbach and Kutas, who observed a graded modulation of electrical brain potentials (N400) to nouns and preceding articles by the probability that people use a word to continue the sentence fragment (‘cloze’). In our direct replication study spanning 9 laboratories (N=334), pre-registered replication-analyses and exploratory Bayes factor analyses successfully replicated the noun-results but, crucially, not the article-results. Pre-registered single-trial analyses also yielded a statistically significant effect for the nouns but not the articles. Exploratory Bayesian single-trial analyses showed that the article-effect may be non-zero but is likely far smaller than originally reported and too small to observe without very large sample sizes. Our results do not support the view that readers routinely pre-activate the phonological form of predictable words.

Abstract

We present a significant extension of the Brain Imaging Data Structure (BIDS) to support the specific
aspects of magnetoencephalography (MEG) data. MEG measures brain activity with millisecond
temporal resolution and unique source imaging capabilities. So far, BIDS was a solution to organise
magnetic resonance imaging (MRI) data. The nature and acquisition parameters of MRI and MEG data
are strongly dissimilar. Although there is no standard data format for MEG, we propose MEG-BIDS as a
principled solution to store, organise, process and share the multidimensional data volumes produced
by the modality. The standard also includes well-defined metadata, to facilitate future data
harmonisation and sharing efforts. This responds to unmet needs from the multimodal neuroimaging
community and paves the way to further integration of other techniques in electrophysiology. MEGBIDS
builds on MRI-BIDS, extending BIDS to a multimodal data structure. We feature several dataanalytics
software that have adopted MEG-BIDS, and a diverse sample of open MEG-BIDS data
resources available to everyone.

Abstract

When combined with source modeling, magneto- (MEG) and electroencephalography (EEG) can be used to study
long-range interactions among cortical processes non-invasively. Estimation of such inter-areal connectivity is
nevertheless hindered by instantaneous field spread and volume conduction, which artificially introduce linear
correlations and impair source separability in cortical current estimates. To overcome the inflating effects of linear
source mixing inherent to standard interaction measures, alternative phase- and amplitude-correlation based
connectivity measures, such as imaginary coherence and orthogonalized amplitude correlation have been proposed.
Being by definition insensitive to zero-lag correlations, these techniques have become increasingly popular
in the identification of correlations that cannot be attributed to field spread or volume conduction. We show here,
however, that while these measures are immune to the direct effects of linear mixing, they may still reveal large
numbers of spurious false positive connections through field spread in the vicinity of true interactions. This
fundamental problem affects both region-of-interest-based analyses and all-to-all connectome mappings. Most
importantly, beyond defining and illustrating the problem of spurious, or “ghost” interactions, we provide a
rigorous quantification of this effect through extensive simulations. Additionally, we further show that signal
mixing also significantly limits the separability of neuronal phase and amplitude correlations. We conclude that
spurious correlations must be carefully considered in connectivity analyses in MEG/EEG source space even when
using measures that are immune to zero-lag correlations.

Abstract

Visual selective attention operates through top–down mechanisms of signal enhancement and suppression, mediated by a-band oscillations. The effects of such top–down signals on local processing in primary visual cortex (V1) remain poorly understood. In this work, we characterize the interplay between large-s cale interactions and local activity changes in V1 that orchestrat es selective attention, using Granger-causality and phase-amplitude coupling (PAC) analysis of EEG source signals. The task required participants to either attend to or ignore oriented gratings. Results from time-varying, directed connectivity analysis revealed frequency-specific effects of attentional selection: bottom–up g-band influences from visual areas increased rapidly in response to attended stimuli while distributed top–down a-band influences originated from parietal cortex in response to ignored stimuli. Importantly, the results revealed a critical interplay between top–down parietal signals and a–g PAC in visual areas.
Parietal a-band influences disrupted the a–g coupling in visual cortex, which in turn reduced the amount of g-band outflow from visual area s. Our results are a first demon stration of how directed interactions affect cross-frequency coupling in downstream areas depending on task demands. These findings suggest that parietal cortex realizes selective attention by disrupting cross-frequency coupling at target regions, which prevents them from propagating task-irrelevant information.

Abstract

The use of immersive virtual reality as a research tool is rapidly increasing in numerous scientific disciplines. By combining ecological validity with strict experimental control, immersive virtual reality provides the potential to develop and test scientific theory in rich environments that closely resemble everyday settings. This article introduces the first standardized database of colored three-dimensional (3D) objects that can be used in virtual reality and augmented reality research and applications. The 147 objects have been normed for name agreement, image agreement, familiarity, visual complexity, and corresponding lexical characteristics of the modal object names. The availability of standardized 3D-objects for virtual reality research is important, as reaching valid theoretical conclusions critically hinges on the use of well controlled experimental stimuli. Sharing standardized 3D-objects across different virtual reality labs will allow for science to move forward more quickly.

Abstract

Bilinguals often switch languages as a function of the language background of their addressee. The control mechanisms supporting bilinguals' ability to select the contextually appropriate language are heavily debated. Here we present four experiments in which unbalanced bilinguals named pictures in their first language Dutch and their second language English in mixed and blocked contexts. Immersive virtual reality technology was used to increase the ecological validity of the cued language-switching paradigm. Behaviorally, we consistently observed symmetrical switch costs, reversed language dominance, and asymmetrical mixing costs. These findings indicate that unbalanced bilinguals apply sustained inhibition to their dominant L1 in mixed language settings. Consequent enhanced processing costs for the L1 in a mixed versus a blocked context were reflected by a sustained positive component in event-related potentials. Methodologically, the use of virtual reality opens up a wide range of possibilities to study language and communication in bilingual and other communicative settings.

Abstract

Different frequency bands in the electroencephalogram are postulated to support distinct language functions. Studies have suggested
that alpha–beta power decreases may index word-retrieval processes. In context-driven word retrieval, participants hear
lead-in sentences that either constrain the final word (‘He locked the door with the’) or not (‘She walked in here with the’). The last
word is shown as a picture to be named. Previous studies have consistently found alpha–beta power decreases prior to picture
onset for constrained relative to unconstrained sentences, localised to the left lateral-temporal and lateral-frontal lobes. However,
the relative contribution of temporal versus frontal areas to alpha–beta power decreases is unknown. We recorded the electroencephalogram
from patients with stroke lesions encompassing the left lateral-temporal and inferior-parietal regions or left-lateral
frontal lobe and from matched controls. Individual participant analyses revealed a behavioural sentence context facilitation effect
in all participants, except for in the two patients with extensive lesions to temporal and inferior parietal lobes. We replicated the
alpha–beta power decreases prior to picture onset in all participants, except for in the two same patients with extensive posterior
lesions. Thus, whereas posterior lesions eliminated the behavioural and oscillatory context effect, frontal lesions did not. Hierarchical
clustering analyses of all patients’ lesion profiles, and behavioural and electrophysiological effects identified those two
patients as having a unique combination of lesion distribution and context effects. These results indicate a critical role for the left
lateral-temporal and inferior parietal lobes, but not frontal cortex, in generating the alpha–beta power decreases underlying context-
driven word production.

Abstract

It has been suggested that external and/or internal limitations paradoxically may lead to superior learning, that is, the concepts of starting small and less is more (Elman, 1993; Newport, 1990). In this paper, we explore the type of incremental ordering during training that might help learning, and what mechanism explains this facilitation. We report four artificial grammar learning experiments with human participants. In Experiments 1a and 1b we found a beneficial effect of starting small using two types of simple recursive grammars: right‐branching and center‐embedding, with recursive embedded clauses in fixed positions and fixed length. This effect was replicated in Experiment 2 (N = 100). In Experiment 3 and 4, we used a more complex center‐embedded grammar with recursive loops in variable positions, producing strings of variable length. When participants were presented an incremental ordering of training stimuli, as in natural language, they were better able to generalize their knowledge of simple units to more complex units when the training input “grew” according to structural complexity, compared to when it “grew” according to string length. Overall, the results suggest that starting small confers an advantage for learning complex center‐embedded structures when the input is organized according to structural complexity.

Abstract

Oscillatory activity in the alpha and gamma bands is considered key in shaping functional brain architecture. Power
increases in the high-frequency gamma band are typically reported in parallel to decreases in the low-frequency alpha
band. However, their functional significance and in particular their interactions are not well understood. The present
study shows that, in the context of an N-backworking memory task, alpha power decreases in the dorsal visual stream
are related to gamma power increases in early visual areas. Granger causality analysis revealed directed interregional
interactions from dorsal to ventral stream areas, in accordance with task demands. Present results reveal a robust,
behaviorally relevant, and architectonically decisive power-to-power relationship between alpha and gamma activity.
This relationship suggests that anatomically distant power fluctuations in oscillatory activity can link cerebral network
dynamics on trial-by-trial basis during cognitive operations such as working memory

Abstract

The auditory steady state evoked response (ASSR) is a robust and frequently utilized
phenomenon in psychophysiological research. It reflects the auditory cortical response
to an amplitude-modulated constant carrier frequency signal. The present report
provides a concrete example of a group analysis of the EEG data from 29 healthy human
participants, recorded during an ASSR paradigm, using the FieldTrip toolbox. First, we
demonstrate sensor-level analysis in the time domain, allowing for a description of the
event-related potentials (ERPs), as well as their statistical evaluation. Second, frequency
analysis is applied to describe the spectral characteristics of the ASSR, followed by
group level statistical analysis in the frequency domain. Third, we show how timeand
frequency-domain analysis approaches can be combined in order to describe
the temporal and spectral development of the ASSR. Finally, we demonstrate source
reconstruction techniques to characterize the primary neural generators of the ASSR.
Throughout, we pay special attention to explaining the design of the analysis pipeline
for single subjects and for the group level analysis. The pipeline presented here can be
adjusted to accommodate other experimental paradigms and may serve as a template
for similar analyses.

Abstract

Prediction can help support rapid language processing. However, it is unclear whether prediction has downstream
consequences, beyond processing in the moment. In particular, when a prediction is disconfirmed, does it linger,
or is it suppressed? This study manipulated whether words were actually seen or were only expected, and probed
their fate in memory by presenting the words (again) a few sentences later. If disconfirmed predictions linger,
subsequent processing of the previously expected (but never presented) word should be similar to actual word
repetition. At initial presentation, electrophysiological signatures of prediction disconfirmation demonstrated that
participants had formed expectations. Further downstream, relative to unseen words, repeated words elicited a
strong N400 decrease, an enhanced late positive complex (LPC), and late alpha band power decreases. Critically,
like repeated words, words previously expected but not presented also attenuated the N400. This “pseudorepetition
effect” suggests that disconfirmed predictions can linger at some stages of processing, and demonstrates
that prediction has downstream consequences beyond rapid on-line processing

Abstract

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

Abstract

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

Abstract

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

Abstract

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

Abstract

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

Abstract

This study examined the role of verbal short-term memory (STM) and executive function (EF) underlying semantic and syntactic interference resolution during sentence comprehension for persons with aphasia (PWA) with varying degrees of STM and EF deficits. Semantic interference was manipulated by varying the semantic plausibility of the intervening NP as subject of the verb and syntactic interference was manipulated by varying whether the NP was another subject or an object. Nine PWA were assessed on sentence reading times and on comprehension question performance. PWA showed exaggerated semantic and syntactic interference effects relative to healthy age-matched control subjects. Importantly, correlational analyses showed that while answering comprehension questions, PWA’ semantic STM capacity related to their ability to resolve semantic but not syntactic interference. In contrast, PWA’ EF abilities related to their ability to resolve syntactic but not semantic interference. Phonological STM deficits were not related to the ability to resolve either type of interference. The results for semantic STM are consistent with prior findings indicating a role for semantic but not phonological STM in sentence comprehension, specifically with regard to maintaining semantic information prior to integration. The results for syntactic interference are consistent with the recent findings suggesting that EF is critical for syntactic processing.

Abstract

When we comprehend language, we often do this in rich settings in which we can use many cues to understand what someone is saying. However, it has traditionally been difficult to design experiments with rich three-dimensional contexts that resemble our everyday environments, while maintaining control over the linguistic and non-linguistic information that is available. Here we test the validity of combining electroencephalography (EEG) and Virtual Reality (VR) to overcome this problem. We recorded electrophysiological brain activity during language processing in a well-controlled three-dimensional virtual audiovisual environment. Participants were immersed in a virtual restaurant, while wearing EEG equipment. In the restaurant participants encountered virtual restaurant guests. Each guest was seated at a separate table with an object on it (e.g. a plate with salmon). The restaurant guest would then produce a sentence (e.g. “I just ordered this salmon.”). The noun in the spoken sentence could either match (“salmon”) or mismatch (“pasta”) with the object on the table, creating a situation in which the auditory information was either appropriate or inappropriate in the visual context. We observed a reliable N400 effect as a consequence of the mismatch. This finding validates the combined use of VR and EEG as a tool to study the neurophysiological mechanisms of everyday language comprehension in rich, ecologically valid settings.

Abstract

The artificial grammar learning (AGL) paradigm enables systematic investigation of the acquisition of linguistically relevant structures. It is a paradigm of interest for language processing research, interfacing with theoretical linguistics, and for comparative research on language acquisition and evolution. This chapter presents a key for understanding major variants of the paradigm. An unbiased summary of neuroimaging findings of AGL is presented, using meta-analytic methods, pointing to the crucial involvement of the bilateral frontal operculum and regions in the right lateral hemisphere. Against a background of robust posterior temporal cortex involvement in processing complex syntax, the evidence for involvement of the posterior temporal cortex in AGL is reviewed. Infant AGL studies testing for neural substrates are reviewed, covering the acquisition of adjacent and non-adjacent dependencies as well as algebraic rules. The language acquisition data suggest that comparisons of learnability of complex grammars performed with adults may now also be possible with children.

Abstract

Learning new vocabulary from context typically requires multiple encounters during which word meaning can be retrieved from memory or inferred from context. We compared the effect of memory retrieval and context inferences on short‐ and long‐term retention in three experiments. Participants studied novel words and then practiced the words either in an uninformative context that required the retrieval of word meaning from memory (“I need the funguo”) or in an informative context from which word meaning could be inferred (“I want to unlock the door: I need the funguo”). The informative context facilitated word comprehension during practice. However, later recall of word form and meaning and word recognition in a new context were better after successful retrieval practice and retrieval practice with feedback than after context‐inference practice. These findings suggest benefits of retrieval during contextualized vocabulary learning whereby the uninformative context enhanced word retention by triggering memory retrieval.

Abstract

Interpersonal discourse particles (DPs), such as Dutch inderdaad (≈‘indeed’) and eigenlijk (≈‘actually’) are highly frequent in everyday conversational interaction. Despite extensive theoretical descriptions of their polyfunctionality, little is known about how they are used by language comprehenders. In two visual world eye-tracking experiments involving an online dialogue completion task, we asked to what extent inderdaad, confirming an inferred expectation, and eigenlijk, contrasting with an inferred expectation, influence real-time understanding of dialogues. Answers in the dialogues contained a DP or a control adverb, and a critical discourse referent was replaced by a beep; participants chose the most likely dialogue completion by clicking on one of four referents in a display. Results show that listeners make rapid and fine-grained situation-specific inferences about the use of DPs, modulating their expectations about how the dialogue will unfold. Findings further specify and constrain theories about the conversation-managing function and polyfunctionality of DPs.

Abstract

In the recent literature, the effects of noninvasive neurostimulation on cognitive functioning appear to lack consistency and replicability. We propose that such effects may be concealed unless dedicated, sensitive, and process-specific dependent measures are used. The expression and subsequent suppression of response capture are often studied using conflict tasks. Response-time distribution analyses have been argued to provide specific measures of the susceptibility to make fast impulsive response errors, as well as the proficiency of the selective suppression of these impulses. These measures of response capture and response inhibition are particularly sensitive to experimental manipulations and clinical deficiencies that are typically obfuscated in commonly used overall performance analyses. Recent work using structural and functional imaging techniques links these behavioral outcome measures to the integrity of frontostriatal networks. These studies suggest that the presupplementary motor area (pre-SMA) is linked to the susceptibility to response capture whereas the right inferior frontal cortex (rIFC) is associated with the selective suppression of action impulses. Here, we used repetitive transcranial magnetic stimulation (rTMS) to test the causal involvement of these two cortical areas in response capture and inhibition in the Simon task. Disruption of rIFC function specifically impaired selective suppression of conflicting action tendencies, whereas the anticipated increase of fast impulsive errors after perturbing pre-SMA function was not confirmed. These results provide a proof of principle of the notion that the selection of appropriate dependent measures is perhaps crucial to establish the effects of neurostimulation on specific cognitive functions.

Abstract

Learning often occurs in communicative and collaborative settings, yet almost all research into the neural basis of memory relies on participants encoding and retrieving information on their own. We investigated whether learning linguistic labels in a collaborative context at least partly relies on cognitively and neurally distinct representations, as compared to learning in an individual context. Healthy human participants learned labels for sets of abstract shapes in three different tasks. They came up with labels with another person in a collaborative communication task (collaborative condition), by themselves (individual condition), or were given pre-determined unrelated labels to learn by themselves (arbitrary condition). Immediately after learning, participants retrieved and produced the labels aloud during a communicative task in the MRI scanner. The fMRI results show that the retrieval of collaboratively generated labels as compared to individually learned labels engages brain regions involved in understanding others (mentalizing or theory of mind) and autobiographical memory, including the medial prefrontal cortex, the right temporoparietal junction and the precuneus. This study is the first to show that collaboration during encoding affects the neural networks involved in retrieval.

Abstract

During a post-encoding delay period, the ongoing consolidation of recently acquired memories can suffer interference if the delay period involves encoding of new memories, or sensory stimulation tasks. Interestingly, two recent independent studies suggest that (i) autobiographical thinking also interferes markedly with ongoing consolidation of recently learned wordlist material, while (ii) a 2-Back task might not interfere with ongoing consolidation, possibly due to the suppression of autobiographical thinking. In this study, we directly compare these conditions against a quiet wakeful rest baseline to test whether the promotion (via familiar sound-cues) or suppression (via a 2-Back task) of autobiographical thinking during the post-encoding delay period can affect consolidation of studied wordlists in a negative or a positive way, respectively. Our results successfully replicate previous studies and show a significant interference effect (as compared to the rest condition) when learning is followed by familiar sound-cues that promote autobiographical thinking, whereas no interference effect is observed when learning is followed by the 2-Back task. Results from a post-experimental experience-sampling questionnaire further show significant differences in the degree of autobiographical thinking reported during the three post-encoding periods: highest in the presence of sound-cues and lowest during the 2-Back task. In conclusion, our results suggest that varying levels of autobiographical thought during the post-encoding period may modulate episodic memory consolidation.

Abstract

Readers and listeners actively predict upcoming words during language processing. These predictions might serve to support the unification of incoming words into sentence context and thus rely on interactions between areas in the language network. In the current magnetoencephalography study, participants read sentences that varied in contextual constraints so that the predictability of the sentence-final words was either high or low. Before the sentence-final words, we observed stronger alpha power suppression for the highly compared with low constraining sentences in the left inferior frontal cortex, left posterior temporal region, and visual word form area. Importantly, the temporal and visual word form area alpha power correlated negatively with left frontal gamma power for the highly constraining sentences. We suggest that the correlation between alpha power decrease in temporal language areas and left prefrontal gamma power reflects the initiation of an anticipatory unification process in the language network.

Abstract

Using magnetoencephalography, the current study examined gamma activity associated with language prediction. Participants read high- and low-constraining sentences in which the final word of the sentence was either expected or unexpected. Although no consistent gamma power difference induced by the sentence-final words was found between the expected and unexpected conditions, the correlation of gamma power during the prediction and activation intervals of the sentence-final words was larger when the presented words matched with the prediction compared with when the prediction was violated or when no prediction was available. This suggests that gamma magnitude relates to the match between predicted and perceived words. Moreover, the expected words induced activity with a slower gamma frequency compared with that induced by unexpected words. Overall, the current study establishes that prediction is related to gamma power correlations and a slowing of the gamma frequency.

Abstract

Verbal working memory (VWM), the ability to maintain and manipulate representations of speech sounds over short periods, is held by some influential models to be independent from the systems responsible for language production and comprehension [e.g., Baddeley, A. D. Working memory, thought, and action. New York, NY: Oxford University Press, 2007]. We explore the alternative hypothesis that maintenance in VWM is subserved by temporary activation of the language production system [Acheson, D. J., & MacDonald, M. C. Verbal working memory and language production: Common approaches to the serial ordering of verbal information. Psychological Bulletin, 135, 50–68, 2009b]. Specifically, we hypothesized that for stimuli lacking a semantic representation (e.g., nonwords such as mun), maintenance in VWM can be achieved by cycling information back and forth between the stages of phonological encoding and articulatory planning. First, fMRI was used to identify regions associated with two different stages of language production planning: the posterior superior temporal gyrus (pSTG) for phonological encoding (critical for VWM of nonwords) and the middle temporal gyrus (MTG) for lexical–semantic retrieval (not critical for VWM of nonwords). Next, in the same subjects, these regions were targeted with repetitive transcranial magnetic stimulation (rTMS) during language production and VWM task performance. Results showed that rTMS to the pSTG, but not the MTG, increased error rates on paced reading (a language production task) and on delayed serial recall of nonwords (a test of VWM). Performance on a lexical–semantic retrieval task (picture naming), in contrast, was significantly sensitive to rTMS of the MTG. Because rTMS was guided by language production-related activity, these results provide the first causal evidence that maintenance in VWM directly depends on the long-term representations and processes used in speech production.

Abstract

The influence of semantic processing on the serial ordering of items in short-term memory was explored using a novel dual-task paradigm. Participants engaged in 2 picture-judgment tasks while simultaneously performing delayed serial recall. List material varied in the presence of phonological overlap (Experiments 1 and 2) and in semantic content (concrete words in Experiment 1 and 3; nonwords in Experiments 2 and 3). Picture judgments varied in the extent to which they required accessing visual semantic information (i.e., semantic categorization and line orientation judgments). Results showed that, relative to line-orientation judgments, engaging in semantic categorization judgments increased the proportion of item-ordering errors for concrete lists but did not affect error proportions for nonword lists. Furthermore, although more ordering errors were observed for phonologically similar relative to dissimilar lists, no interactions were observed between the phonological overlap and picture-judgment task manipulations. These results demonstrate that lexical-semantic representations can affect the serial ordering of items in short-term memory. Furthermore, the dual-task paradigm provides a new method for examining when and how semantic representations affect memory performance.

Abstract

Research on written language comprehension has generally assumed that the phonological properties of a word have little effect on sentence comprehension beyond the processes of word recognition. Two experiments investigated this assumption. Participants silently read relative clauses in which two pairs of words either did or did not have a high degree of phonological overlap. Participants were slower reading and less accurate comprehending the overlap sentences compared to the non-overlapping controls, even though sentences were matched for plausibility and differed by only two words across overlap conditions. A comparison across experiments showed that the overlap effects were larger in the more difficult object relative than in subject relative sentences. The reading patterns showed that phonological representations affect not only memory for recently encountered sentences but also the developing sentence interpretation during on-line processing. Implications for theories of sentence processing and memory are discussed. Highlights The work investigates the role of phonological information in sentence comprehension, which is poorly understood. ► Subjects read object and subject relative clauses +/- phonological overlap in two pairs of words. ► Unique features of the study were online reading measures and pinpointed overlap locations. ► Phonological overlap slowed reading speed and impaired sentence comprehension, especially for object relatives. ► The results show a key role for phonological information during online comprehension, not just later sentence memory.

Abstract

The current study investigated which time components of rapid automatized naming (RAN) predict group differences between dyslexic and non-dyslexic readers (matched for age and reading level), and how these components relate to different reading measures. Subjects performed two RAN tasks (letters and objects), and data were analyzed through a response time analysis. Our results demonstrated that impaired RAN performance in dyslexic readers mainly stem from enhanced inter-item pause times and not from difficulties at the level of post-access motor production (expressed as articulation rates). Moreover, inter-item pause times account for a significant proportion of variance in reading ability in addition to the effect of phonological awareness in the dyslexic group. This suggests that non-phonological factors may lie at the root of the association between RAN inter-item pauses and reading ability. In normal readers, RAN performance was associated with reading ability only at early ages (i.e. in the reading-matched controls), and again it was the RAN inter-item pause times that explain the association.

Abstract

In the present study, the authors investigate how some visual factors related to early stages of visual-object naming modulate naming performance in dyslexia. The performance of dyslexic children was compared with 2 control groups—normal readers matched for age and normal readers matched for reading level—while performing a discrete naming task in which color and dimensionality of the visually presented objects were manipulated. The results showed that 2-dimensional naming performance improved for color representations in control readers but not in dyslexics. In contrast to control readers, dyslexics were also insensitive to the stimulus's dimensionality. These findings are unlikely to be explained by a phonological processing problem related to phonological access or retrieval but suggest that dyslexics have a lower capacity for coding and decoding visual surface features of 2-dimensional representations or problems with the integration of visual information stored in long-term memory.

Abstract

This article summarizes some of the important findings from research evaluating the relationship between poor rapid naming and impaired reading performance. Substantial evidence shows that dyslexic readers have problems with rapid naming of visual items. Early research assumed that this was a consequence of phonological processing deficits, but recent findings suggest that non-phonological processes may lie at the root of the association between slow naming speed and poor reading. The hypothesis that rapid naming reflects an independent core deficit in dyslexia is supported by the main findings: (1) some dyslexics are characterized by rapid naming difficulties but intact phonological skills; (2) evidence for an independent association between rapid naming and reading competence in the dyslexic readers, when the effect of phonological skills was controlled; (3) rapid naming and phonological processing measures are not reliably correlated. Recent research also reveals greater predictive power of rapid naming, in particular the inter-item pause time, for high-frequency word reading compared to pseudoword reading in developmental dyslexia. Altogether, the results are more consistent with the view that a phonological component alone cannot account for the rapid naming performance in dyslexia. Rather, rapid naming problems may emerge from the inefficiencies in visual-orthographic processing as well as in phonological processing.

Abstract

At least three cognitive brain components are necessary in order for us to be able to produce and comprehend language: a Memory repository for the lexicon, a Unification buffer where lexical information is combined into novel structures, and a Control apparatus presiding over executive function in language. Here we describe the brain networks that support Memory and Unification in semantics. A dynamic account of their interactions is presented, in which a balance between the two components is sought at each word-processing step. We use the theory to provide an explanation of the N400 effect.

Abstract

Space and time appear to be related asymmetrically in the child’s mind: temporal representations depend on spatial representations more than vice versa, as predicted by space-time metaphors in language. In a study supporting this conclusion, spatial information interfered with children’s temporal judgments more than vice versa (Casasanto, Fotakopoulou, & Boroditsky, 2010, Cognitive Science). In this earlier study, however, spatial information was available to participants for more time than temporal information was (as is often the case when people observe natural events), suggesting a skeptical explanation for the observed effect. Here we conducted a stronger test of the hypothesized space-time asymmetry, controlling spatial and temporal aspects of the stimuli even more stringently than they are generally ’controlled’ in the natural world. Results replicated Casasanto and colleagues’, validating their finding of a robust representational asymmetry between space and time, and extending it to children (4-10 y.o.) who speak Dutch and Brazilian Portuguese.

Abstract

In this study, we systematically review the scientific literature on the effect of color on object recognition. Thirty-five independent experiments, comprising 1535 participants, were included in a meta-analysis. We found a moderate effect of color on object recognition (d = 0.28). Specific effects of moderator variables were analyzed and we found that color diagnosticity is the factor with the greatest moderator effect on the influence of color in object recognition; studies using color diagnostic objects showed a significant color effect (d = 0.43), whereas a marginal color effect was found in studies that used non-color diagnostic objects (d = 0.18). The present study did not permit the drawing of specific conclusions about the moderator effect of the object recognition task; while the meta-analytic review showed that color information improves object recognition mainly in studies using naming tasks (d = 0.36), the literature review revealed a large body of evidence showing positive effects of color information on object recognition in studies using a large variety of visual recognition tasks. We also found that color is important for the ability to recognize artifacts and natural objects, to recognize objects presented as types (line-drawings) or as tokens (photographs), and to recognize objects that are presented without surface details, such as texture or shadow. Taken together, the results of the meta-analysis strongly support the contention that color plays a role in object recognition. This suggests that the role of color should be taken into account in models of visual object recognition.

Abstract

In the present study, the authors explore in detail the level of visual object recognition at which perceptual color information improves the recognition of color diagnostic and noncolor diagnostic objects. To address this issue, 3 object recognition tasks, with different cognitive demands, were designed: (a) an object verification task; (b) a category verification task; and (c) a name verification task. They found that perceptual color information improved color diagnostic object recognition mainly in tasks for which access to the semantic knowledge about the object was necessary to perform the task; that is, in category and name verification. In contrast, the authors found that perceptual color information facilitates noncolor diagnostic object recognition when access to the object’s structural description from long-term memory was necessary—that is, object verification. In summary, the present study shows that the role of perceptual color information in object recognition is dependent on color diagnosticity

Abstract

If concepts, categories, and word meanings are stable, how can people use them so flexibly? Here we explore a possible answer: maybe this stability is an illusion. Perhaps all concepts, categories, and word meanings (CC&Ms) are constructed ad hoc, each time we use them. On this proposal, all words are infinitely polysemous, all communication is ’good enough’, and no idea is ever the same twice. The details of people’s ad hoc CC&Ms are determined by the way retrieval cues interact with the physical, social, and linguistic context. We argue that even the most stable-seeming CC&Ms are instantiated via the same processes as those that are more obviously ad hoc, and vary (a) from one microsecond to the next within a given instantiation, (b) from one instantiation to the next within an individual, and (c) from person to person and group to group as a function of people’s experiential history. 826

Abstract

Do people with different kinds of bodies think differently? According to the bodyspecificity hypothesis (Casasanto 2009), they should. In this article, I review evidence that right- and left-handers, who perform actions in systematically different ways, use correspondingly different areas of the brain for imagining actions and representing the meanings of action verbs. Beyond concrete actions, the way people use their hands also influences the way they represent abstract ideas with positive and negative emotional valence like “goodness,” “honesty,” and “intelligence,” and how they communicate about them in spontaneous speech and gesture. Changing how people use their right and left hands can cause them to think differently, suggesting that motoric differences between right- and left-handers are not merely correlated with cognitive differences. Body-specific patterns of motor experience shape the way we think, communicate, and make decisions

Abstract

Right- and left-handers implicitly associate positive ideas like "goodness"and "honesty"more strongly with their dominant side
of space, the side on which they can act more fluently, and negative ideas more strongly with their nondominant side. Here we show that right-handers’ tendency to associate "good" with "right" and "bad" with "left" can be reversed as a result of both
long- and short-term changes in motor fluency. Among patients who were right-handed prior to unilateral stroke, those with disabled left hands associated "good" with "right," but those with disabled right hands associated "good" with "left,"as natural left-handers do. A similar pattern was found in healthy right-handers whose right or left hand was temporarily handicapped in the laboratory. Even a few minutes of acting more fluently with the left hand can change right-handers’ implicit associations between space and emotional valence, causing a reversal of their usual judgments. Motor experience plays a causal role in shaping abstract thought.

Abstract

Can simple motor actions help people expand their vocabulary? Here we show that word learning depends on where students place their flash cards after studying them. In Experiment 1, participants learned the definitions of ”alien words” with positive or negative emotional valence. After studying each card, they placed it in one of two boxes (top or bottom), according to its valence. Participants who were instructed to place positive cards in the top box, consistent with Good is Up metaphors, scored about 10.

Abstract

1 Introduction In spoken sentence processing, listeners do not wait till the end of a sentence to decipher what message is conveyed. Rather, they make predictions on the most plausible interpretation at every possible point in the auditory signal on the basis of all kinds of linguistic information (e.g., Eberhard et al. 1995; Alman and Kamide 1999, 2007). Intonation is one such kind of linguistic information that is efficiently used in spoken sentence processing. The evidence comes primarily from recent work on online reference resolution conducted in the visual-world eyetracking paradigm (e.g., Tanenhaus et al. 1995). In this paradigm, listeners are shown a visual scene containing a number of objects and listen to one or two short sentences about the scene. They are asked to either inspect the visual scene while listening or to carry out the action depicted in the sentence(s) (e.g., 'Touch the blue square'). Listeners' eye movements directed to each object in the scene are monitored and time-locked to pre-defined time points in the auditory stimulus. Their predictions on the upcoming referent and sources for the predictions in the auditory signal are examined by analysing fixations to the relevant objects in the visual scene before the acoustic information on the referent is available

Abstract

People spontaneously produce gestures when they solve problems or explain their solutions to a problem. In this chapter, we will review and discuss evidence on the role of representational gestures in problem solving. The focus will be on our recent experiments (Chu & Kita, 2008), in which we used Shepard-Metzler type of mental rotation tasks to investigate how spontaneous gestures revealed the development of problem solving strategy over the course of the experiment and what role gesture played in the development process. We found that when solving novel problems regarding the physical world, adults go through similar symbolic distancing (Werner & Kaplan, 1963) and internalization (Piaget, 1968) processes as those that occur during young children’s cognitive development and gesture facilitates such processes.

Abstract

Methods
The present study provides a systematic analysis of co-speech gestures which spontaneously accompany the description of actions in a group of PD patients (N = 23, Hoehn and Yahr Stage III or less) and age-matched healthy controls (N = 22). The analysis considers different co-speech gesture types, using established classification schemes from the field of gesture research. The analysis focuses on the rate of these gestures as well as on their qualitative nature. In doing so, the analysis attempts to overcome several methodological shortcomings of research in this area.
Results
Contrary to expectation, gesture rate was not significantly affected in our patient group, with relatively mild PD. This indicates that co-speech gestures could compensate for speech problems. However, while gesture rate seems unaffected, the qualitative precision of gestures representing actions was significantly reduced.
Conclusions
This study demonstrates the feasibility of carrying out fine-grained, detailed analyses of gestures in PD and offers insights into an as yet neglected facet of communication in patients with PD. Based on the present findings, an important next step is the closer investigation of the qualitative changes in gesture (including different communicative situations) and an analysis of the heterogeneity in co-speech gesture production in PD.

Abstract

Many children with Specific Language Impairment (SLI) show impairments in discriminating auditorily presented stimuli. The present study investigates whether these discrimination problems are speech specific or of a general auditory nature. This was studied by using a linguistic and nonlinguistic contrast that were matched for acoustic complexity in an active behavioral task and a passive ERP paradigm, known to elicit the mismatch negativity (MMN). In addition, attention skills and a variety of language skills were measured. Participants were 25 five-year-old Dutch children with SLI having receptive as well as productive language problems and 25 control children with typical speechand language development. At the behavioral level, the SLI group was impaired in discriminating the linguistic contrast as compared to the control group, while both groups were unable to distinguish the non-linguistic contrast. Moreover, the SLI group tended to have impaired attention skills which correlated with performance on most of the language tests. At the neural level, the SLI group, in contrast to the control group, did not show an MMN in response to either the linguistic or nonlinguistic contrast. The MMN data are consistent with an account that relates the symptoms in children with SLI to non-speech processing difficulties.

Abstract

Language is a hallmark of our species and understanding linguistic diversity is an area of major interest. Genetic factors influencing the cultural transmission of language provide a powerful and elegant explanation for aspects of the present day linguistic diversity and a window into the emergence and evolution of language. In particular, it has recently been proposed that linguistic tone—the usage of voice pitch to convey lexical and grammatical meaning—is biased by two genes involved in brain growth and development, ASPM and Microcephalin. This hypothesis predicts that tone is a stable characteristic of language because of its ‘genetic anchoring’. The present paper tests this prediction using a Bayesian phylogenetic framework applied to a large set of linguistic features and language families, using multiple software implementations, data codings, stability estimations, linguistic classifications and outgroup choices. The results of these different methods and datasets show a large agreement, suggesting that this approach produces reliable estimates of the stability of linguistic data. Moreover, linguistic tone is found to be stable across methods and datasets, providing suggestive support for the hypothesis of genetic influences on its distribution.

Abstract

Investigating human cognitive faculties such as language, attention, and memory most often relies on testing small and homogeneous groups of volunteers coming to research facilities where they are asked to participate in behavioral experiments. We show that this limitation and sampling bias can be overcome by using smartphone technology to collect data in cognitive science experiments from thousands of subjects from all over the world. This mass coordinated use of smartphones creates a novel and powerful scientific ‘‘instrument’’ that yields the data necessary to test universal theories of cognition. This increase in power represents a potential revolution in cognitive science

Abstract

Relative clause processing depends on the grammatical role of the head noun in the subordinate clause. This has traditionally been explained in terms of cognitive limitations. We suggest that structure-related processing differences arise from differences in experience with these structures. We present a connectionist model which learns to produce utterances with relative clauses from exposure to message-sentence pairs. The model shows how various factors such as frequent subsequences, structural variations, and meaning conspire to create differences in the processing of these structures. The predictions of this learning-based account have been confirmed in behavioral studies with adults. This work shows that structural regularities that govern relative clause processing can be explained within a usage-based approach to recursion.

Abstract

The present study addresses questions concerning bilinguals’ attainment in the two languages by investigating the extent to which early bilinguals manage to apply the information structure required in each language when producing a complex text. In re-narrating the content of a film, speakers have to break down the perceived series of dynamic situations and structure relevant information into units that are suited for linguistic expression. The analysis builds on typological studies of Germanic and Romance languages which investigate the role of grammaticized concepts in determining core features in information structure. It takes a global perspective in that it focuses on factors that determine information selection and information structure that hold in macrostructural terms for the text as a whole (factors driving information selection, the temporal frame used to locate events on the time line, and the means used in reference management). A first comparison focuses on Dutch and German monolingual native speakers and shows that despite overall typological similarities, there are subtle though systematic differences between the two languages in the aforementioned areas of information structure. The analyses of the bilinguals focus on their narratives in both languages, and compares the patterns found to those found in the monolingual narratives. Findings show that the method used provides insights into the individual bilingual’s attainment in the two languages and identifies either balanced levels of attainment, patterns showing higher degrees of conformity with one of the languages, as well as bilingual-specific patterns of performance.

Abstract

This paper focuses on native speaker judgments of a construction in Dutch that functions as a progressive aspectual marker (aan het X zijn, referred to as aan het-construction) and represents an event as in progression at the time of speech. The method was chosen in order to investigate how native speakers assess the scope and conditions of use of a construction which is in the process of grammaticalization. It allows for the inclusion of a large group of participants of different age groups and an investigation of potential age-related differences. The study systematically covers a range of temporal variables that were shown to be relevant in elicitation and corpus-based studies on the grammaticalization of progressive aspect constructions. The results provide insights into the selectional preferences and constraints of the aan het-construction in contemporary Dutch, as judged by native speakers, and the extent to which they correlate with production tasks.

Abstract

The first objective of this study was to compare the brain network engaged by preference classification and the standard grammaticality classification after implicit artificial syntax acquisition by re-analyzing previously reported event-related fMRI data. The results show that preference and grammaticality classification engage virtually identical brain networks, including Broca’s region, consistent with previous behavioral findings. Moreover, the results showed that the effects related to artificial syntax in Broca’s region were essentially the same when masked with variability related to natural syntax processing in the same participants. The second objective was to explore CNTNAP2-related effects in implicit artificial syntax learning by analyzing behavioral and event-related fMRI data from a subsample. The CNTNAP2 gene has been linked to specific language impairment and is controlled by the FOXP2 transcription factor. CNTNAP2 is expressed in language related brain networks in the developing human brain and the FOXP2–CNTNAP2 pathway provides a mechanistic link between clinically distinct syndromes involving disrupted language. Finally, we discuss the implication of taking natural language to be a neurobiological system in terms of bounded recursion and suggest that the left inferior frontal region is a generic on-line sequence processor that unifies information from various sources in an incremental and recursive manner.

Abstract

During face-to-face communication, one does not only hear speech but also see a speaker's communicative hand movements. It has been shown that such hand gestures play an important role in communication where the two modalities influence each other's interpretation. A gesture typically temporally overlaps with coexpressive speech, but the gesture is often initiated before (but not after) the coexpressive speech. The present ERP study investigated what degree of asynchrony in the speech and gesture onsets are optimal for semantic integration of the concurrent gesture and speech. Videos of a person gesturing were combined with speech segments that were either semantically congruent or incongruent with the gesture. Although gesture and speech always overlapped in time, gesture and speech were presented with three different degrees of asynchrony. In the SOA 0 condition, the gesture onset and the speech onset were simultaneous. In the SOA 160 and 360 conditions, speech was delayed by 160 and 360 msec, respectively. ERPs time locked to speech onset showed a significant difference between semantically congruent versus incongruent gesture–speech combinations on the N400 for the SOA 0 and 160 conditions. No significant difference was found for the SOA 360 condition. These results imply that speech and gesture are integrated most efficiently when the differences in onsets do not exceed a certain time span because of the fact that iconic gestures need speech to be disambiguated in a way relevant to the speech context.

Abstract

Students who are learning to write in a foreign language, often want feedback on the grammatical quality of the sentences they produce. The usual NLP approach to this problem is based on parsing student-generated text. Here, we propose a generation-based ap- proach aiming at preventing errors ("scaffolding"). In our ICALL system, the student constructs sentences by composing syntactic trees out of lexically anchored "treelets" via a graphical drag & drop user interface. A natural-language generator computes all possible grammatically well-formed sentences entailed by the student-composed tree. It provides positive feedback if the student-composed tree belongs to the well-formed set, and negative feedback otherwise. If so requested by the student, it can substantiate the positive or negative feedback based on a comparison between the student-composed tree and its own trees (informative feedback on demand). In case of negative feedback, the system refuses to build the structure attempted by the student. Frequently occurring errors are handled in terms of "malrules." The system we describe is a prototype (implemented in JAVA and C++) which can be parameterized with respect to L1 and L2, the size of the lexicon, and the level of detail of the visually presented grammatical structures.

Abstract

The present paper explores cross-cultural variation in spatial cognition by comparing spatial reconstruction tasks by Dutch and Namibian elementary school children. These two communities differ in the way they predominantly express spatial relations in language. Four experiments investigate cognitive strategy preferences across different levels of task-complexity and instruction. Data show a correlation between dominant linguistic spatial frames of reference and performance patterns in non-linguistic spatial memory tasks. This correlation is shown to be stable across an increase of complexity in the spatial array. When instructed to use their respective non-habitual cognitive strategy, participants were not easily able to switch between strategies and their attempts to do so impaired their performance. These results indicate a difference not only in preference but also in competence and suggest that spatial language and non-linguistic preferences and competences in spatial cognition are systematically aligned across human populations.

Abstract

Mimicry has been observed regarding a range of nonverbal behaviors, but only recently have researchers started to investigate mimicry in co-speech gestures. These gestures are considered to be crucially different from other aspects of nonverbal behavior due to their tight link with speech. This study provides evidence of mimicry in co-speech gestures in face-to-face dialogue, the most common forum of everyday talk. In addition, it offers an analysis of the functions that mimicked co-speech gestures fulfill in the collaborative process of creating a mutually shared understanding of referring expressions. The implications bear on theories of gesture production, research on grounding, and the mechanisms underlying behavioral mimicry.

Abstract

This study uses a classical referential communication task to
investigate the role of co-speech gestures in the process of
coordination. The study manipulates both the common ground between the interlocutors, as well as the visibility of the gestures they use. The findings show that co-speech gestures are an integral part of the referential utterances speakers
produced with regard to both initial references as well as repeated references, and that the availability of gestures appears to impact on interlocutors’ referential oordination. The results are discussed with regard to past research on
common ground as well as theories of gesture production.

Abstract

There is evidence that co-speech gestures communicate information to addressees and that they are often communicatively intended. However, we still know comparatively little about the role of gestures in the actual process of communication. The present study offers a systematic investigation of speakers’ gesture use before and after addressee feedback. The findings show that when speakers responded to addressees’ feedback gesture rate remained constant when this feedback encouraged clarification, elaboration or correction. However, speakers gestured proportionally less often after feedback when providing confirmatory responses. That is, speakers may not be drawing on gesture in response to addressee feedback per se, but particularly with responses that enhance addressees’ understanding. Further, the large majority of speakers’ gestures changed in their form. They tended to be more precise, larger, or more visually prominent after feedback. Some changes in gesture viewpoint were also observed. In addition, we found that speakers used deixis in speech and gaze to increase the salience of gestures occurring in response to feedback. Speakers appear to conceive of gesture as a useful modality in redesigning utterances to make them more accessible to addressees. The findings further our understanding of recipient design and co-speech gestures in face-to-face dialogue.
Highlights

► Gesture rate remains constant in response to addressee feedback when the response aims to correct or clarify understanding. ► But gesture rate decreases when speakers provide confirmatory responses to feedback signalling correct understanding. ► Gestures are more communicative in response to addressee feedback, particularly in terms of precision, size and visual prominence. ► Speakers make gestures in response to addressee feedback more salient by using deictic markers in speech and gaze.

Abstract

Studies exploring the role of neural oscillations in cognition have revealed sustained increases in alpha-band (∼8–14 Hz) power during the delay period of delayed-recognition short-term memory tasks. These increases have been proposed to reflect the inhibition, for example, of cortical areas representing task-irrelevant information, or of potentially interfering representations from previous trials. Another possibility, however, is that elevated delay-period alpha-band power (DPABP) reflects the selection and maintenance of information, rather than, or in addition to, the inhibition of task-irrelevant information. In the present study, we explored these possibilities using a delayed-recognition paradigm in which the presence and task relevance of shape information was systematically manipulated across trial blocks and electroencephalographic was used to measure alpha-band power. In the first trial block, participants remembered locations marked by identical black circles. The second block featured the same instructions, but locations were marked by unique shapes. The third block featured the same stimulus presentation as the second, but with pretrial instructions indicating, on a trial-by-trial basis, whether memory for shape or location was required, the other dimension being irrelevant. In the final block, participants remembered the unique pairing of shape and location for each stimulus. Results revealed minimal DPABP in each of the location-memory conditions, whether locations were marked with identical circles or with unique task-irrelevant shapes. In contrast, alpha-band power increases were observed in both the shape-memory condition, in which location was task irrelevant, and in the critical final condition, in which both shape and location were task relevant. These results provide support for the proposal that alpha-band oscillations reflect the retention of shape information and/or shape–location associations in short-term memory.

Abstract

Baby's begrijpen woorden eerder dan dat ze deze zeggen. Dit stadium is onderbelicht want moeilijk waarneembaar. Caroline Junge onderzocht de vaardigheden die nodig zijn voor het leren van de eerste woordjes: conceptherkenning, woordherkenning en het verbinden van woord aan betekenis. Daarvoor bestudeerde ze de hersenpotentialen van het babybrein tijdens het horen van woordjes. Junge stelt vast dat baby's van negen maanden al woordbegrip hebben. En dat is veel vroeger dan tot nu toe bekend was. Als baby's een woord hoorde dat niet klopte met het plaatje dat ze zagen, lieten ze een N400-effect zien, een klassiek hersenpotentiaal. Uit eerder Duits onderzoek is gebleken dat baby's van twaalf maanden dit effect nog niet laten zien, omdat de hersenen nog niet rijp zouden zijn. Het onderzoek van Junge weerlegt dit. Ook laat ze zien dat als baby's goed woorden kunnen herkennen binnen zinnetjes, dit belangrijk is voor hun latere taalontwikkeling, wat mogelijk tot nieuwe therapieën voor taalstoornissen zal leiden.