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Article first published online: January 13, 2020 Humans quickly adapt to variations in the speech signal. Adaptation may surface as recalibration, a learning effect driven by error-minimisation between a visual face and an ambiguous auditory speech signal, or as selective adaptation, a contrastive aftereffect driven by the acoustic clarity of the sound. Here, we examined whether these aftereffects occur for vowel identity and voice gender. Participants were exposed to male, female, or androgynous tokens of speakers pronouncing /e/, /ø/, (embedded in words with a consonant-vowel-consonant structure), or an ambiguous vowel halfway between /e/ and /ø/ dubbed onto the video of a male or female speaker pronouncing /e/ or /ø/. For both voice gender and vowel identity, we found assimilative aftereffects after exposure to auditory ambiguous adapter sounds, and contrastive aftereffects after exposure to auditory clear adapter sounds. This demonstrates that similar principles for adaptation in these dimensions are at play. The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This research was supported by Gravitation Grant 024.001.006 of the Language in Interaction Consortium from Netherlands Organization for Scientific Research. The third author was supported by The Netherlands Organization for Scientific Research (NWO: VENI Grant 275-89-027).

Lip-reading is crucial for understanding speech in challenging conditions. But how the brain extracts meaning from--silent--visual speech is still under debate. Lip-reading in silence activates the auditory cortices, but it is not known whether such activation reflects immediate synthesis of the corresponding auditory stimulus or imagery of unrelated sounds.To disentangle these possibilities, we used magnetoencephalography to evaluate how cortical activity in 28 healthy adults humans (17 females) entrained to the auditory speech envelope and lip movements (mouth opening) when listening to a spoken story without visual input (audio-only), and when seeing a silent video of a speaker articulating another story (video-only).In video-only, auditory cortical activity entrained to the absent auditory signal at frequencies below 1 Hz more than to the seen lip movements. This entrainment process was characterized by an auditory-speech-to-brain delay of ∼70 ms in the left hemisphere, compared to ∼20 ms in audio-only Entrainment to mouth opening was found in the right angular gyrus at below 1 Hz, and in early visual cortices at 1-8 Hz.These findings demonstrate that the brain can use a silent lip-read signal to synthesize a coarse-grained auditory speech representation in early auditory cortices. Our data indicate the following underlying oscillatory mechanism: Seeing lip movements first modulates neuronal activity in early visual cortices at frequencies that match articulatory lip movements; the right angular gyrus then extracts slower features of lip movements, mapping them onto the corresponding speech sound features; this information is fed to auditory cortices, most likely facilitating speech parsing.SIGNIFICANCE STATEMENTLip-reading consists in decoding speech based on visual information derived from observation of a speaker's articulatory facial gestures. Lip reading is known to improve auditory speech understanding, especially when speech is degraded. Interestingly, lip-reading in silence still activates the auditory cortices, even when participants do not know what the absent auditory signal should be. However, it was uncertain what such activation reflected. Here, using magnetoencephalographic recordings, we demonstrate it reflects fast synthesis of the auditory stimulus rather than mental imagery of unrelated--speech or non-speech--sounds. Our results also shed light on the oscillatory dynamics underlying lip-reading., info:eu-repo/semantics/published

Published: 22 March 2019. Although the default state of the world is that we see and hear other people talking, there is evidence that seeing and hearing ourselves rather than someone else may lead to visual (i.e., lip-read) or auditory “self” advantages. We assessed whether there is a “self” advantage for phonetic recalibration (a lip-read driven cross-modal learning effect) and selective adaptation (a contrastive effect in the opposite direction of recalibration). We observed both aftereffects as well as an on-line effect of lip-read information on auditory perception (i.e., immediate capture), but there was no evidence for a “self” advantage in any of the tasks (as additionally supported by Bayesian statistics). These findings strengthen the emerging notion that recalibration reflects a general learning mechanism, and bolster the argument that adaptation depends on rather low-level auditory/acoustic features of the speech signal. This work was supported by the Severo Ochoa program grant SEV-2015-049 awarded to the BCBL. MB and MP were supported by the Spanish Ministry of Economy and Competitiveness (MINECO, grant PSI2014-51874-P), and MB was also supported by the Netherlands Organization for Scientific Research (NWO, VENI grant 275-89-027).

Available online 1 September 2018. There is considerable behavioral evidence that morphologically complex words such as ‘tax-able’ and ‘kiss-es’ are processed and represented combinatorially. In other words, they are decomposed into their constituents ‘tax’ and ‘-able’ during comprehension (reading or listening), and producing them might also involve on–the–spot combination of these constituents (especially for inflections). However, despite increasing amount of neurocognitive research, the neural mechanisms underlying these processes are still not fully understood. The purpose of this critical review is to offer a comprehensive overview on the state-of-the-art of the research on the neural mechanisms of morphological processing. In order to take into account all types of complex words, we include findings on inflected, derived, and compound words presented both visually and aurally. More specifically, we cover a wide range of electro- and magnetoencephalography (EEG and MEG, respectively) as well as structural/functional magnetic resonance imaging (s/fMRI) studies that focus on morphological processing. We present the findings with respect to the temporal course and localization of morphologically complex word processing. We summarize the observed findings, their interpretations with respect to current psycholinguistic models, and discuss methodological approaches as well as their possible limitations. This study was supported by Kone Foundation and Helsinki University Research Grants to Alina Leminen, by the Volkswagen Foundation, Grant FP 561/11 to Eva Smolka, PSI2015- 65689-P and SEV-2015-0490 from the Spanish Government (Jon Andoni Du~nabeitia).

Speech perception is influenced by vision through a process of audiovisual integration. This is demonstrated by the McGurk illusion where visual speech (for example /ga/) dubbed with incongruent auditory speech (such as /ba/) leads to a modified auditory percept (/da/). Recent studies have indicated that perception of the incongruent speech stimuli used in McGurk paradigms involves mechanisms of both general and audiovisual speech specific mismatch processing and that general mismatch processing modulates induced theta-band (4-8 Hz) oscillations. Here, we investigated whether the theta modulation merely reflects mismatch processing or, alternatively, audiovisual integration of speech. We used electroencephalographic recordings from two previously published studies using audiovisual sine-wave speech (SWS), a spectrally degraded speech signal sounding nonsensical to naive perceivers but perceived as speech by informed subjects. Earlier studies have shown that informed, but not naive subjects integrate SWS phonetically with visual speech. In an N1/P2 event-related potential paradigm, we found a significant difference in theta-band activity between informed and naive perceivers of audiovisual speech, suggesting that audiovisual integration modulates induced theta-band oscillations. In a McGurk mismatch negativity paradigm (MMN) where infrequent McGurk stimuli were embedded in a sequence of frequent audio-visually congruent stimuli we found no difference between congruent and McGurk stimuli. The infrequent stimuli in this paradigm are violating both the general prediction of stimulus content, and that of audiovisual congruence. Hence, we found no support for the hypothesis that audiovisual mismatch modulates induced theta-band oscillations. We also did not find any effects of audiovisual integration in the MMN paradigm, possibly due to the experimental design.

We investigated the role of executive control processes in the activation of manual affordances in two experiments combining stimulus-response compatibility (SRC) and dual-task paradigms. We registered an inverse SRC effect in the presence of a parallel backward-counting task in Experiment 1, and a cancellation of the SRC effect in Experiment 2 when a parallel Stroop-like task was used. We interpret our data as supporting a self-inhibition account of the affordance activation control. Accordingly, the role of executive processes is to prevent self-inhibition in supraliminal conditions: when cognitive resources are depleted by a parallel task, the self-inhibition mechanism becomes active and irrelevantly potentiated affordances are inhibited, leading to the emergence of an inverse SRC effect. In addition, the difference between data patterns observed in the two experiments suggests that the exact roles of the executive processes involved during the activation of affordances may differ. The results suggest a mechanism for action-related activation monitoring based on a flexible control over automatically potentiated actions. The paper discusses the proposed mechanism in detail and outlines further research directions.

Cognitive flexibility has been studied in two separate research traditions. Neuropsychologists typically rely on rather complex assessment tools such as the Wisconsin Card Sorting Test (WCST). In contrast, task-switching paradigms are used in experimental psychology to obtain more specific measures of cognitive flexibility. We aim to contribute to the integration of these research traditions by examining the role of the key factor that differs between the WCST and experimental task-switching paradigms: rule uncertainty. In two experimental studies, we manipulated the degree of rule uncertainty after rule switches in a computerized version of the WCST. Across a variety of task parameters, reducing rule uncertainty consistently impaired the speed and accuracy of responses when the rule designated to be more likely turned out to be incorrect. Other performance measures such as the number of perseverative errors were not significantly affected by rule uncertainty. We conclude that a fine-grained analysis of WCST performance can dissociate behavioural indicators that are affected vs. unaffected by rule uncertainty. By this means, it is possible to integrate WCST results and findings obtained from task-switching paradigms that do not involve rule uncertainty. ispartof: ACTA PSYCHOLOGICA vol:190 pages:53-64 ispartof: location:Netherlands status: published

Item does not contain fulltext 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. 27 p.

The cognitive view on deception proposes that lying comes with a cognitive cost. This view is supported by the finding that lying typically takes longer than truth telling. Event-related potentials (ERPs) provide a means to unravel the cognitive processes underlying this cost. Using a mock-crime design, the current study (n = 20) investigated the effects of deception on the Contingent Negative Variation (CNV), the Lateralized Readiness Potential (LRP), the Correct Response Negativity (CRN), and the stimulus-locked N200 and P300 components. In line with previous research, lying resulted in more errors, longer reaction times (RTs) and longer RT standard deviations compared to truthful responses. A marginally significant effect suggested a stronger CNV for the anticipation of lying compared to the anticipation of truth telling. There were no significant deception effects on the stimulus- and the response-locked LRPs. Unexpectedly, we found a significantly larger CRN for truth telling compared to lying. Additional analyses revealed an enhanced N200 and a decreased P300 for lying compared to truth telling. Our results support the cognitive load hypothesis for lying, yet are mixed regarding the response conflict hypothesis. Results are discussed with regard to the specific characteristics of our design and their theoretical and applied implications.

Objectives: Bulimia nervosa (BN) is associated with a deficit of self-regulatory control and impulsivity. The present study aimed to clarify whether an impaired inhibitory control due to hyperarousal underlies impulsivity in BN subjects. Methods: Event-related potentials (ERPs) were recorded in 17 female patients with BN and 17 healthy controls during a three-tone oddball task. ERP components related to inhibition of irrelevant distractor stimuli, as well as effortful processing, were analyzed. Standardized low-resolution electromagnetic tomography (sLORETA) was used to assess ERP source activity. Results: Compared to healthy controls, BN patients showed reduced amplitude and shorter latency of the N200 (N2), increased amplitude and shorter latency of the target slow wave (SW), and higher amplitude of the P300 for distractor stimuli (P3a) and for targets (P3b). sLORETA showed the following: (1) higher activity of the P3a generators in the left parietal cortex, bilateral precuneus and right frontal and anterior cingulate for distractor stimuli and (2) lower activity of the SW generators in the left medial frontal gyrus, bilateral superior frontal, anterior cingulate and cuneus for target stimuli. The reduction of the N2 latency was associated with the Barratt scores for impulsiveness. Conclusions: The observed electrophysiological abnormalities suggest a condition of hyperarousal, with impaired suppression of irrelevant stimuli due to abnormal cortical activation and reduced signal-to-noise ratio. Our findings point to functional abnormalities within a neural system that subserves attention and self-regulatory control, which may contribute to impulsive behaviors in BN.

Recent studies have revealed a strong relationship between visual working memory and selective attention, such that attention is biased by what is currently on our mind. However, other data show that not all memorized items influence the deployment of attention, thus calling for a distinction within working memory: whereas active memory items function as an attentional template and directly affect perception, other, accessory items do not. We review recent evidence that items compete for the status of 'attentional template' that contains only one object at a time. Neurophysiological results provide insight into these different memory states by revealing a more intricate organization of working memory than was previously thought. © 2011 Elsevier Ltd.

We investigated whether it is possible to control the temporal window of attention used to rapidly integrate visual information. To study the underlying neural mechanisms, we recorded ERPs in an attentional blink task, known to elicit Lag-1 sparing. Lag-1 sparing fosters joint integration of the two targets, evidenced by increased order errors. Short versus long integration windows were induced by showing participants mostly fast or slow stimuli. Participants expecting slow speed used a longer integration window, increasing joint integration. Difference waves showed an early (200 ms post-T2) negative and a late positive modulation (390 ms) in the fast group, but not in the slow group. The modulations suggest the creation of a separate event for T2, which is not needed in the slow group, where targets were often jointly integrated. This suggests that attention can be guided by global expectations of presentation speed within tens of milliseconds.

Visual search and oddball paradigms were combined to investigate memory for to-be-ignored color changes in a group of 12 healthy participants. The onset of unexpected color change of an irrelevant stimulus evoked two reliable ERP effects: a component of the event-related potential (ERP), similar to the visual mismatch negativity response (vMMN), with a latency of 120-160 ms and a posterior distribution over the left hemisphere and Late Fronto-Central Negativity (LFCN) with a latency of 320-400 ms, apparent at fronto-central electrodes and some posterior sites. Color change of that irrelevant stimulus also slowed identification of a visual target, indicating distraction. The amplitude of this color-change vMMN, but not LFCN, indexed this distraction effect. That is, electrophysiological and behavioral measures were correlated. The interval between visual scenes approximated 1 s (611-1629 ms), indicating that the brain's sensory memory for the color of the preceding visual scenes must persist for at least 600 ms. Therefore, in the case of the neural code for color, durable memory representations are formed in an obligatory manner. (C) 2014 Elsevier B.V. All rights reserved.

Spoken word recognition and production require fast transformations between acoustic, phonological, and conceptual neural representations. Bilinguals perform these transformations in native and non-native languages, deriving unified semantic concepts from equivalent, but acoustically different words. Here we exploit this capacity of bilinguals to investigate input invariant semantic representations in the brain. We acquired EEG data while Dutch subjects, highly proficient in English listened to four monosyllabic and acoustically distinct animal words in both languages (e.g., "paard"-"horse"). Multivariate pattern analysis (MVPA) was applied to identify EEG response patterns that discriminate between individual words within one language (within-language discrimination) and generalize meaning across two languages (across-language generalization). Furthermore, employing two EEG feature selection approaches, we assessed the contribution of temporal and oscillatory EEG features to our classification results. MVPA revealed that within-language discrimination was possible in a broad time-window (~50-620 ms) after word onset probably reflecting acoustic-phonetic and semantic-conceptual differences between the words. Most interestingly, significant across-language generalization was possible around 550-600 ms, suggesting the activation of common semantic-conceptual representations from the Dutch and English nouns. Both types of classification, showed a strong contribution of oscillations below 12 Hz, indicating the importance of low frequency oscillations in the neural representation of individual words and concepts. This study demonstrates the feasibility of MVPA to decode individual spoken words from EEG responses and to assess the spectro-temporal dynamics of their language invariant semantic-conceptual representations. We discuss how this method and results could be relevant to track the neural mechanisms underlying conceptual encoding in comprehension and production.

Contains fulltext : 55621.pdf (Publisher’s version ) (Closed access) This study examined auditory processing in 2-month-old infants at genetic risk for dyslexia and in controls. Manipulated natural speech stimuli (/bAk/ and /dAk/), at either side of the phoneme boundary, were presented to these infants and their automatic cortical deviance responses were recorded. Control infants showed two distinct mismatch responses, thus extending similar findings reported with kindergartners in terms of topographical distribution and cortical sources. The absence of such mismatch responses in the infants at risk supports the hypothesis of basic auditory (temporal) processing impairments in the disorder. The results suggest that these early signs of deficient auditory processing may point to problematic categorical perception at a later age. 6 p.

The ERP experiment reported here addresses some outstanding questions regarding word processing in sentential contexts: (1) Does only the 'message-level' representation (the representation of sentence meaning combining lexico-semantic and syntactic constraints) affect the processing of the incoming word [J. Exp. Psychol.: Learn. Mem. Cogn. 20 (1994) 92]? (2) Is lexically specified semantic relatedness between multiple words the primary factor instead [J. Exp. Psychol.: Learn. Mem. Cogn. 15 (1989) 791]? (3) Alternatively, do word and sentence level information interact during sentence comprehension? Volunteers read sentences (e.g. Dutch sentences resembling The javelin was by the athletes...) in which the (passive) syntactic structure and the semantic content of the lexical items together created a strong expectation of a specific final word (e.g., thrown), but also sentences in which the syntactic structure was changed from passive to active (e.g. Dutch sentences resembling The javelin has the athletes...), which altered the message level constraint substantially and strongly reduced. the expectation of any particular completion. Half of the sentences ended in a final word with a good lexico-semantic fit relative to the preceding content words (e.g. thrown, fitting well with the preceding javelin and athletes). This creates very plausible sentences in the strong constraint context but semantically anomalous ones in the weakly constraining context (e.g., The javelin has the athletes thrown). In the other half the final word had a poor lexico-semantic fit (e.g., summarized that does not fit at all with javelin and athletes). Good lexico-semantic fit endings showed no difference in N400 amplitude in the strong and weak message-level constraint sentences, despite the fact that the latter were semantically anomalous. This result suggests that lexico-semantic fit can be more important for word processing than the meaning of the sentence as determined by the syntactic structure, at least initially. These conditions did differ, however, in the region of the P600 where the anomalous weak constraint version was much more positive, a pattern usually seen with ungrammatical sentences. The processing of poor lexicosemantic fit words showed a quite different pattern; in both strong and weak constraint sentences they elicited a substantial N400 effect, but N400-amplitude was significantly more negative following strong constraint contexts, even though both sentence contexts were equivalently anomalous. Taken together, these findings provide evidence for the importance of both message-level and lexico-semantic information during sentence comprehension. The implications for theories of sentence interpretation are discussed and an extension of the message-based hypothesis will be proposed. (C) 2003 Elsevier B.V. All rights reserved.

Many perceptual decision making models posit that participants accumulate noisy evidence over time to improve the accuracy of their decisions, and that in free response tasks, participants respond when the accumulated evidence reaches a decision threshold. Research on the neural correlates of these models' components focuses primarily on evidence accumulation. Far less attention has been paid to the neural correlates of decision thresholds, reflecting the final commitment to a decision. Inspired by a model of bistable neural activity that implements a decision threshold, we reinterpret human lateralized readiness potentials (LRPs) as reflecting the crossing of a decision threshold. Interestingly, this threshold crossing preserves signatures of a drift-diffusion process of evidence accumulation that feeds in to the threshold mechanism. We show that, as our model predicts, LRP amplitudes and growth rates recorded while participants performed a motion discrimination task correlate with individual differences in behaviorally-estimated prior beliefs, decision thresholds and evidence accumulation rates. As such LRPs provide a useful measure to test dynamical models of both evidence accumulation and decision commitment processes non-invasively. © 2014 van Vugt et al.

Item does not contain fulltext Most words that infants hear occur within fluent speech. To compile a vocabulary, infants therefore need to segment words from speech contexts. This study is the first to investigate whether infants (here: 10-month-olds) can recognize words when both initial exposure and test presentation are in continuous speech. Electrophysiological evidence attests that this indeed occurs: An increased extended negativity (word recognition effect) appears for familiarized target words relative to control words. This response proved constant at the individual level: Only infants who showed this negativity at test had shown such a response, within six repetitions after first occurrence, during familiarization. 15 p.

The ability to extract word forms from continuous speech is a prerequisite for constructing a vocabulary and emerges in the first year of life. Electrophysiological (ERP) studies of speech segmentation by 9- to 12-month-old listeners in several languages have found a left-localized negativity linked to word onset as a marker of word detection. We report an ERP study showing significant evidence of speech segmentation in Dutch-learning 7-month-olds. In contrast to the left-localized negative effect reported with older infants, the observed overall mean effect had a positive polarity. Inspection of individual results revealed two participant sub-groups: a majority showing a positive-going response, and a minority showing the left negativity observed in older age groups. We retested participants at age three, on vocabulary comprehension and word and sentence production. On every test, children who at 7 months had shown the negativity associated with segmentation of words from speech outperformed those who had produced positive-going brain responses to the same input. The earlier that infants show the left-localized brain responses typically indicating detection of words in speech, the better their early childhood language skills. - See more at: http://www.frontiersin.org/Language_Sciences/10.3389/fpsyg.2013.00025/abstract#sthash.uNXBLdzM.dpuf

Patients with classic galactosemia, an inborn error of metabolism, have speech and language production impairments. Past research primarily focused on speech (motor) problems, but these cannot solely explain the language impairments. Which specific deficits contribute to the impairments in language production is not yet known. Deficits in semantic and syntactic planning are plausible and require further investigation. In the present study, we examined syntactic encoding while patients and matched controls overtly described scenes of moving objects using either separate words (minimal syntactic planning) or sentences (sentence-level syntactic planning). The design of the paradigm also allowed tapping into local noun phrase- and more global sentence-level syntactic planning. Simultaneously, we recorded event-related potentials (ERPs). The patients needed more time to prepare and finish the utterances and made more errors. The patient ERPs had a very similar morphology to that of healthy controls, indicating overall comparable neural processing. Most importantly, the ERPs diverged from those of controls in several functionally informative time windows, ranging from very early (90-150 ms post scene onset) to relatively late (1820-2020 ms post scene onset). These time windows can be associated with different linguistic encoding stages. The ERP results form the first neuroscientific evidence for language production impairments in patients with galactosemia in lexical and syntactic planning stages, i.e., prior to the linguistic output phase. These findings hence shed new light on the language impairments in this disease.

Facing response conflict, subjects try to improve their responses by reducing the influence of the detrimental information which caused the conflict. It was speculated that this adaptation to conflict can only occur when the conflicting information is consciously perceived. In this review we give an overview of the research looking at the possibility of unconscious stimuli to provoke this conflict adaptation. In a first part we discuss adaptation to conflict on a trial-by-trial basis. When the previous trial contained conflicting information, subjects will adapt to this by reducing the influence of the conflicting information on the current trial. However, the interesting question is whether this is also possible when the conflicting information remains unconscious. In a second part we will discuss blockwise adaptation to conflict. If conflict is very frequent, subjects will adapt to this by reducing the conflicting information sustainably. Again the question is whether this is possible when the conflict was never experienced consciously. In a third part we will discuss the neural basis of conscious and unconscious conflict adaptation. We will critically discuss the research on these topics and highlight strengths and weaknesses of the used paradigms. Finally, we will give some suggestions how future research can be more conclusive in this respect. ispartof: FRONTIERS IN HUMAN NEUROSCIENCE vol:6 issue:FEBRUARY 2012 ispartof: location:Switzerland status: published

Converging electrophysiological and brain-imaging results show that sensory processing in V1 can be modulated by attention. In this study, we tested the prediction that this early filtering effect depends on the current affective state of the participant. We recorded visual evoked potentials (VEPs) to visual peripheral distractors while participants performed a demanding task at fixation, whose perceptual load was manipulated in a parametric fashion. Crucially, levels of negative affect were either increased or decreased independently of changes in perceptual load. Concurrent psychophysiological measurements and self-report scales confirmed that changes in emotional state were effective. In the control condition, ERP results showed that the C1 component generated in response to the exact same peripheral distractors systematically varied in amplitude with the amount of perceptual load imposed at fixation, being larger when perceptual load decreased. However, this early modulatory effect in V1 was disrupted when participants transiently experienced increased state anxiety, resulting in a decreased C1 amplitude even though task load at fixation remained low. These results suggest that early bottom-up processing in V1 is not only influenced by the amount of attention resources available, but also by the current internal state of the participant.

Background: Most people show a remarkable deficit to report the second of two targets when presented in close temporal succession, reflecting an attentional blink (AB). An aspect of the AB that is often ignored is that there are large individual differences in the magnitude of the effect. Here we exploit these individual differences to address a long-standing question: does attention to a visual target come at a cost for attention to an auditory target (and vice versa)? More specifically, the goal of the current study was to investigate a) whether individuals with a large within-modality AB also show a large cross-modal AB, and b) whether individual differences in AB magnitude within different modalities correlate or are completely separate.Methodology/Principal Findings: While minimizing differential task difficulty and chances for a task-switch to occur, a significant AB was observed when targets were both presented within the auditory or visual modality, and a positive correlation was found between individual within-modality AB magnitudes. However, neither a cross-modal AB nor a correlation between cross-modal and within-modality AB magnitudes was found.Conclusion/Significance: The results provide strong evidence that a major source of attentional restriction must lie in modality-specific sensory systems rather than a central amodal system, effectively settling a long-standing debate. Individuals with a large within-modality AB may be especially committed or focused in their processing of the first target, and to some extent that tendency to focus could cross modalities, reflected in the within-modality correlation. However, what they are focusing (resource allocation, blocking of processing) is strictly within-modality as it only affects the second target on within-modality trials. The findings show that individual differences in AB magnitude can provide important information about the modular structure of human cognition.

Increasing evidence suggests that working memory and perceptual processes are dynamically interrelated due to modulating activity in overlapping brain networks. However, the direct influence of working memory on the spatio-temporal brain dynamics of behaviorally relevant intervening information remains unclear. To investigate this issue, subjects performed a visual proximity grid perception task under three different visual-spatial working memory (VSWM) load conditions. VSWM load was manipulated by asking subjects to memorize the spatial locations of 6 or 3 disks. The grid was always presented between the encoding and recognition of the disk pattern. As a baseline condition, grid stimuli were presented without a VSWM context. VSWM load altered both perceptual performance and neural networks active during intervening grid encoding. Participants performed faster and more accurately on a challenging perceptual task under high VSWM load as compared to the low load and the baseline condition. Visual evoked potential (VEP) analyses identified changes in the configuration of the underlying sources in one particular period occurring 160-190 ms post-stimulus onset. Source analyses further showed an occipito-parietal down-regulation concurrent to the increased involvement of temporal and frontal resources in the high VSWM context. Together, these data suggest that cognitive control mechanisms supporting working memory may selectively enhance concurrent visual processing related to an independent goal. More broadly, our findings are in line with theoretical models implicating the engagement of frontal regions in synchronizing and optimizing mnemonic and perceptual resources towards multiple goals.

Name agreement is the extent to which different people agree on a name for a particular picture. Previous studies have found that it takes longer to name low name agreement pictures than high name agreement pictures. To examine the effect of name agreement in the online process of picture naming, we compared event-related potentials (ERPs) recorded whilst 19 healthy, native English speakers silently named pictures which had either high or low name agreement. A series of ERP components was examined: P1 approximately 120 ms from picture onset, N1 around 170 ms, P2 around 220 ms, N2 around 290 ms, and P3 around 400 ms. Additionally, a late time window from 800 to 900 ms was considered. Name agreement had an early effect, starting at P1 and possibly resulting from uncertainty of picture identity, and continuing into N2, possibly resulting from alternative names for pictures. These results support the idea that name agreement affects two consecutive processes: first, object recognition, and second, lexical selection and/or phonological encoding. (C) 2010 Elsevier B.V. All rights reserved.

Dyslexics have problems with categorization of speech sounds, in particular when rapid temporal processing is involved such as in formant transitions of stop-consonants. Infants are already sensitive to such auditory features, but here we show that precursors of impaired categorization are already present in the brain responses of two-month-old infants at familial risk for dyslexia. Natural speech stimuli (/bAk/ and /dAk/), at either side of the phoneme boundary, induced multiple mismatch responses in control infants tinder pre-attentive and pre-cognitive conditions. Infants at-risk showed an attenuated early mismatch response and an absent late one, in addition to diminished cortical activity in the left hemisphere. These results are consistent with a temporal processing deficit in the infants at risk and may point to an early precursor of the disorder. (C) 2007 Published by Elsevier Ltd.

The amplitude of the pattern visual evoked potential (VEP) of a binocular stimulus has been shown to be generally larger than the VEP obtained monocularly. There is evidence that this effect can be considered an electrophysiological index of fusion. To study how binocular vision develops in infancy we evaluated the incremental binocular amplitude (IBA) in three infants in a longitudinal investigation during the first five months of life. The stimuli were phase-alternating square-wave gratings with spatial and temporal parameters chosen to be appropriate for neonates. IBA was defined as the percentage increment of the largest binocular response compared with the monocular response. In the first two months of life IBA values were near zero, that is, no summation occurred. Between the second and third month IBA values rose markedly and after the third month its value was greater than 100%, demonstrating binocular facilitation. Thus in the first two months of life the eyes do not seem to cooperate as in adults. By the second and third month the binocular pattern VEP reflects an increasing binocular interaction. Other studies of the development of stereopsis have also found evidence of binocularity at similar ages.