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Contains fulltext : 293019.pdf (Publisher’s version ) (Open Access) Several theories of predictive processing propose reduced sensory and neural responses to anticipated events. Support comes from magnetoencephalography/electroencephalography (M/EEG) studies, showing reduced auditory N1 and P2 responses to self-generated compared to externally generated events, or when the timing and form of stimuli are more predictable. The current study examined the sensitivity of N1 and P2 responses to statistical speech regularities. We employed a motor-to-auditory paradigm comparing event-related potential (ERP) responses to externally and self-triggered pseudowords. Participants were presented with a cue indicating which button to press (motor–auditory condition) or which pseudoword would be presented (auditory-only condition). Stimuli consisted of the participant's own voice uttering pseudowords that varied in phonotactic probability and syllable stress. We expected to see N1 and P2 suppression for self-triggered stimuli, with greater suppression effects for more predictable features such as high phonotactic probability and first-syllable stress in pseudowords. In a temporal principal component analysis (PCA), we observed an interaction between syllable stress and condition for the N1, where second-syllable stress items elicited a larger N1 than first-syllable stress items, but only for externally generated stimuli. We further observed an effect of syllable stress on the P2, where first-syllable stress items elicited a larger P2. Strikingly, we did not observe motor-induced suppression for self-triggered stimuli for either the N1 or P2 component, likely due to the temporal predictability of the stimulus onset in both conditions. Taking into account previous findings, the current results suggest that sensitivity to syllable stress regularities depends on task demands. 18 p.

Despite good control of phenylalanine (Phe) levels during childhood and adolescence, adults with phenylketonuria (PKU) often show abnormalities in the white matter of the brain, which have been associated with poorer cognitive performance. However, whether such a relationship exists with cortical gray matter is still unknown. Therefore, we investigated cortical thickness and surface area in adults with early-treated PKU and their relationship to cognitive functions and metabolic control. We included 30 adult patients with early-treated and metabolically well-controlled PKU (median age: 35.5 years) and 54 healthy controls (median age: 29.3 years). Surface-based morphometry was derived from T1-weighted magnetic resonance images using FreeSurfer, and general intelligence, executive functions, and attention were assessed. Concurrent plasma Phe, tyrosine, and tryptophan levels were measured in patients. In addition, Phe levels were collected retrospectively to calculate the index of dietary control. Patients showed a thinner cortex than controls in regions of the bilateral temporal, parietal, and occipital lobes (effect size r = -0.34 to -0.42, p 0.05). No group differences in surface area were found. In patients, accuracy in the working memory task was positively correlated with thickness in the left insula (r = 0.45, p = 0.013), left fusiform gyrus (r = 0.39, p = 0.032), and right superior temporal gyrus (r = 0.41, p = 0.024), but did not survive false discovery rate correction. Neither concurrent nor historical metabolic parameters were related to cortical thickness. Taken together, adults with PKU showed widespread reductions in cortical thickness despite good metabolic control in childhood and adolescence. However, alterations in cortical thickness were unrelated to metabolic parameters and cognitive performance.

Some theories of predictive processing propose reduced sensory and neural responses to anticipated events. Support comes from M/EEG studies, showing reduced auditory N1 and P2 responses to self-compared to externally generated events, or when stimulus properties are more predictable (e.g. prototypical). The current study examined the sensitivity of N1 and P2 responses to statistical regularities of speech. We employed a motor-to-auditory paradigm comparing ERP responses to externally and self-generated pseudowords, varying in phonotactic probability and syllable stress. We expected to see N1 and P2 suppression for self-generated stimuli, with greater suppression effect for more predictable features such as high phonotactic probability and first syllable stress in pseudowords. We observe an interaction between phonotactic probability and condition on the N1 amplitude, with an enhanced effect of phonotactic probability in processing self-generated stimuli. However, the directionality of this effect was reversed compared to what was expected, namely a larger N1 amplitude for high probability items, possibly indicating a perceptual bias toward the more predictable item. We further observed an effect of syllable stress on the P2 amplitude, with greater amplitudes in response to first syllable stress items. The current results suggest that phonotactic probability plays an important role in processing self-generated speech, supporting feedforward models involved in speech production.

Predictions of our sensory environment facilitate perception across domains. During speech perception, formal and temporal predictions may be made for phonotactic probability and syllable stress patterns, respectively, contributing to the efficient processing of speech input. The current experiment employed a passive EEG oddball paradigm to probe the neurophysiological processes underlying temporal and formal predictions simultaneously. The component of interest, the mismatch negativity (MMN), is considered a marker for experience-dependent change detection, where its timing and amplitude are indicative of the perceptual system's sensitivity to presented stimuli. We hypothesized that more predictable stimuli (i.e. high phonotactic probability and first syllable stress) would facilitate change detection, indexed by shorter peak latencies or greater peak amplitudes of the MMN. This hypothesis was confirmed for phonotactic probability: high phonotactic probability deviants elicited an earlier MMN than low phonotactic probability deviants. We do not observe a significant modulation of the MMN to variations in syllable stress. Our findings confirm that speech perception is shaped by formal and temporal predictability. This paradigm may be useful to investigate the contribution of implicit processing of statistical regularities during (a)typical language development. Maastricht University (Grant to BMJ to support women in higher academic positions) and Netherlands Organization for Scientific Research (NWO) 452-16-004 info:eu-repo/semantics/publishedVersion

Published: 21 December 2020 About one third of patients with epilepsy have seizures refractory to the medical treatment. Electrical stimulation mapping (ESM) is the gold standard for the identification of “eloquent” areas prior to resection of epileptogenic tissue. However, it is time-consuming and may cause undesired side effects. Broadband gamma activity (55–200 Hz) recorded with extraoperative electrocorticography (ECoG) during cognitive tasks may be an alternative to ESM but until now has not proven of definitive clinical value. Considering their role in cognition, the alpha (8–12 Hz) and beta (15–25 Hz) bands could further improve the identification of eloquent cortex. We compared gamma, alpha and beta activity, and their combinations for the identification of eloquent cortical areas defined by ESM. Ten patients with intractable focal epilepsy (age: 35.9 ± 9.1 years, range: 22–48, 8 females, 9 right handed) participated in a delayed-match-to-sample task, where syllable sounds were compared to visually presented letters. We used a generalized linear model (GLM) approach to find the optimal weighting of each band for predicting ESM-defined categories and estimated the diagnostic ability by calculating the area under the receiver operating characteristic (ROC) curve. Gamma activity increased more in eloquent than in non-eloquent areas, whereas alpha and beta power decreased more in eloquent areas. Diagnostic ability of each band was close to 0.7 for all bands but depended on multiple factors including the time period of the cognitive task, the location of the electrodes and the patient’s degree of attention to the stimulus. We show that diagnostic ability can be increased by 3–5% by combining gamma and alpha and by 7.5–11% when gamma and beta were combined. We then show how ECoG power modulation from cognitive testing can be used to map the probability of eloquence in individual patients and how this probability map can be used in clinical settings to optimize ESM planning. We conclude that the combination of gamma and beta power modulation during cognitive testing can contribute to the identification of eloquent areas prior to ESM in patients with refractory focal epilepsy. This work was supported by grants from the Colombian Administrative Department of Science, Technology and Innovation, COLCIENCIAS Colombia (scholarship call 568 to MEA-M).

Electrical stimulation mapping (ESM) is the gold standard for identification of “eloquent” areas prior to resection of epileptogenic tissue, however, it is time consuming and may cause side effects, especially stimulation-induced seizures and after-discharges. Broadband gamma activity (55 – 200 Hz) recorded with subdural electrocorticography (ECoG) during cognitive tasks has been proposed as an attractive tool for mapping cortical areas with specific function but until now has not proven definitive clinical value. Fewer studies have addressed whether the alpha (8 – 12 Hz) and beta (15 – 25 Hz) band activity could also be used to improve eloquent cortex identification. We compared alpha, beta and broadband gamma activity, and their combination for the identification of eloquent cortical areas defined by ESM. Ten patients participated in a delayed-match-to-sample task, where syllable sounds were matched to visually presented letters and responses given by keyboard. We used a generalized linear model (GLM) approach to find the optimal weighting of low frequency bands and broadband gamma power to predict the ESM categories. Broadband gamma activity increased more in eloquent areas than in non-eloquent areas and this difference had a diagnostic ability (area under (AU) the receiving operating characteristic curve - AUROC) of ∼70%. Both alpha and beta power decreased more in eloquent areas. Alpha power had lower AUROC than broadband gamma while beta had similar AUROC. AUROC was enhanced by the combination of alpha and broadband gamma (3% improvement) and by the combination of beta and broadband gamma (7% improvement) over the use of broadband gamma alone. Further analysis showed that the relative performance of broadband gamma and low frequency bands depended on multiple factors including the time period of the cognitive task, the location of the electrodes and the patient’s attention to the stimulus. However, the combination of beta band and broadband gamma always gave the best performance. We show how ECoG power modulation from cognitive testing periods can be used to map the probability of eloquence by ESM and how this probability can be used as an aid for optimal ESM planning. We conclude that low frequency power during cognitive testing can contribute to the identification of eloquent areas in patients with focal refractory epilepsy improving its precision but does not replace the need of ESM.HighlightsGamma, alpha and beta band activity has significant diagnostic ability to identify ESM defined eloquent cortical areas.We present a novel method to combine gamma and low frequency activity for enhanced identification.We quantify how identification is dependent on analysis time window, cortical function, and patient’s attentional engagement.With further development, this approach may offer an alternative to ESM mapping with reduced burden for patients.

Brain impairments have been observed in patients with classic galactosemia, an inherited metabolic disorder resulting in a particular neuro-cognitive profile. Neuroimaging studies showed abnormalities such as diffuse white mater (WM) abnormalities and grey matter (GM) atrophy. Our current study analysed grey matter density using voxel-based morphometry (VBM) and compared the brains of eight adolescent patients with classic galactosemia with eight healthy gender- and aged-matched controls. GM density differences were found in several regions. Decreased GM density was found in the patients in the bilateral putamen and bilateral occipital cortex. Increased GM density in the patients, on the other hand, was found in the bilateral inferior frontal and medial prefrontal cortex. The anatomical profile of the abnormalities is in line with the neuro-cognitive profile of patients with classic galactosemia, including motor dysfunction, speech and language difficulties and higher order cognitive problems. Less favourable GM densities in patients (either increased or decreased compared to controls) correlated with younger age, a worse visual working memory performance, and an older age at initiation of the galactose-restricted diet. To conclude, this explorative study is the first to analyse the GM using VBM in this population, and demonstrates a mixed profile of both increased and decreased GM density in these patients.

The evident degree of heterogeneity observed in reading disabled children has puzzled reading researchers for decades. Recent advances in the genetic underpinnings of reading disability have indicated that the heritable, familial risk for dyslexia is a major risk factor. The present data-driven, classification attempt aims to revisit the possibility of identifying distinct cognitive deficit profiles in a large sample of second to fourth grade reading disabled children. In this sample, we investigated whether genetic and environmental risk factors are able to distinguish between poor reader subtypes. In this profile, we included reading-related measures of phonemic awareness, letter-speech sound processing and rapid naming, known as candidate vulnerability markers associated with dyslexia and familial risk for dyslexia, as well as general cognitive abilities (non-verbal IQ and vocabulary). Clustering was based on a 200 multi-start K-means approach. Results revealed four emerging subtypes of which the first subtype showed no cognitive deficits underlying their poor reading skills (Reading-only impaired poor readers). The other three subtypes shared a core phonological deficit (PA) with a variable and discriminative expression across the other underlying vulnerability markers. More specific, type 2 showed low to poor performance across all reading-related and general cognitive abilities (general poor readers), type 3 showed a specific letter-speech sound mapping deficit next to a PA deficit (PA-LS specific poor readers) and type 4 showed a specific rapid naming deficit complementing their phonological weakness (PA-RAN specific poor readers). The first three poor reader profiles were more characterized by variable environmental risk factor, while the fourth, PA-RAN poor reader subtype showed a significantly strong familial risk for dyslexia. Overall, when we zoom in on the heterogeneous phenomenon of reading disability, unique and distinct cognitive subtypes can be identified, distinguishing between those poor readers more influences by the role of genes and those more influenced by environmental risk factors. Taking into account this diversity of distinct cognitive subtypes, instead of looking at the reading disabled sample as a whole, will help tailor future diagnostic and intervention efforts more specifically to the needs of children with such a specific deficit and risk pattern, as well as providing a more promising way forward for genetic studies of dyslexia.

Sensorimotor integration, the translation between acoustic signals and motoric programs, may constitute a crucial mechanism for speech. During speech perception, the acoustic-motoric translations include the recruitment of cortical areas for the representation of speech articulatory features, such as place of articulation. Selective attention can shape the processing and performance of speech perception tasks. Whether and where sensorimotor integration takes place during attentive speech perception remains to be explored. Here, we investigate articulatory feature representations of spoken consonant-vowel (CV) syllables during two distinct tasks. Fourteen healthy humans attended to either the vowel or the consonant within a syllable in separate delayed-match-to-sample tasks. Single-trial fMRI blood oxygenation level-dependent (BOLD) responses from perception periods were analyzed using multivariate pattern classification and a searchlight approach to reveal neural activation patterns sensitive to the processing of place of articulation (i.e., bilabial/labiodental vs. alveolar). To isolate place of articulation representation from acoustic covariation, we applied a cross-decoding (generalization) procedure across distinct features of manner of articulation (i.e., stop, fricative, and nasal). We found evidence for the representation of place of articulation across tasks and in both tasks separately: for attention to vowels, generalization maps included bilateral clusters of superior and posterior temporal, insular, and frontal regions; for attention to consonants, generalization maps encompassed clusters in temporoparietal, insular, and frontal regions within the right hemisphere only. Our results specify the cortical representation of place of articulation features generalized across manner of articulation during attentive syllable perception, thus supporting sensorimotor integration during attentive speech perception and demonstrating the value of generalization.

Landau-Kleffner Syndrome (LKS) is a rare form of acquired aphasia in children, characterized by epileptic discharges, which occur mostly during sleep. After normal speech and language development, aphasia develops between the ages of 3-7 years in a period ranging from days to months. The epileptic discharges usually disappear after reaching adulthood, but language outcomes are usually poor if no treatment focused on restoration of (non-) verbal communication is given. Patients often appear deaf-mute, but sign language, as part of the treatment, may lead to recovery of communication. The neural mechanisms underlying poor language outcomes in LKS are not yet understood. In this detailed functional MRI study of a recovered LKS patient - that is, a patient no longer suffering from epileptic discharges, audiovisual multi-sensory processing was investigated, since LKS patients are often proficient in reading, but not in speech perception. In the recovered LKS patient a large difference in the neural activation to auditory stimuli was found in the left versus the right auditory cortex, which cannot be attributed to hearing loss. Compared to healthy proficient readers investigated earlier with the same fMRI experiment, the patient demonstrated normal letter-sound integration in the superior temporal gyrus as demonstrated by the multi-sensory interaction index, indicating intact STG function. Diffusion Tensor Imaging (DTI) based fiber tracking in the LKS patient showed fibers originating from Heschl's gyrus that seem to be left-right inverted with respect to FIG fiber pattern described in the literature for healthy controls. In the patient, in both hemispheres we found arcuate fibers projecting from (homologues of) Broca's to Wernicke's areas, and a lack of fibers from arcuate left inferior parietal and sylvian areas reported in healthy subjects. We observed short arcuate segments in the right hemisphere. Although speculative, our results suggest intact temporal lobe processing but an altered temporal to frontal connectivity. The altered connectivity might explain observed short-term verbal memory problems, disturbed (speech) sound-motor interaction and online feedback of speech and might be one of the neuronal factors underlying LKS. (c) 2015 Elsevier Inc. All rights reserved.

Patients with classic galactosemia, a genetic metabolic disorder, encounter cognitive impairments, including motor (speech), language, and memory deficits. We used functional magnetic resonance imaging to evaluate spontaneous functional connectivity during rest to investigate potential abnormalities in neural networks. We characterized networks using seed-based correlation analysis in 13 adolescent patients and 13 matched controls. Results point towards alterations in several networks, including well-known resting-state networks (e.g. default mode, salience, visual network). Particularly, patients showed alterations in networks encompassing medial prefrontal cortex, parietal lobule and (pre)cuneus, involved in spatial orientation and attention. Furthermore, altered connectivity of networks including the insula and superior frontal gyrus -important for sensory-motor integration and motor (speech) planning- was demonstrated. Lastly, abnormalities were found in networks involving occipital regions, linked to visuospatial capacities and working memory. Importantly, across several seeds, altered functional connectivity to the superior frontal cortex, anterior insula, parietal lobule and the (pre)cuneus was observed in patients, suggesting special importance of these brain regions. Moreover, these alterations correlated with neurocognitive test results, supporting a relation with the clinical phenotype. Our findings contribute to improved characterization of brain impairments in classic galactosemia and provide directions for further investigations.

In a shooting video game we investigated whether increased distance reduces moral conflict. We measured and analyzed the event related potential (ERP), including the N2 component, which has previously been linked to cognitive conflict from competing decision tendencies. In a modified Go/No-go task designed to trigger moral conflict participants had to shoot suddenly appearing human like avatars in a virtual reality scene. The scene was seen either from an ego perspective with targets appearing directly in front of the participant or from a bird's view, where targets were seen from above and more distant. To control for low level visual features, we added a visually identical control condition, where the instruction to "shoot" was replaced by an instruction to "detect." ERP waveforms showed differences between the two tasks as early as in the N1 time-range, with higher N1 amplitudes for the close perspective in the "shoot" task. Additionally, we found that pre-stimulus alpha power was significantly decreased in the ego, compared to the bird's view only for the "shoot" but not for the "detect" task. In the N2 time window, we observed main amplitude effects for response (No-go > Go) and distance (ego > bird perspective) but no interaction with task type (shoot vs. detect). We argue that the pre-stimulus and N1 effects can be explained by reduced attention and arousal in the distance condition when people are instructed to "shoot." These results indicate a reduced moral engagement for increased distance. The lack of interaction in the N2 across tasks suggests that at that time point response execution dominates. We discuss potential implications for real life shooting situations, especially considering recent developments in drone shootings which are per definition of a distant view.

BACKGROUND: Classic galactosemia is an autosomal recessive disorder due to galactose-1-phosphate uridyltransferase (GALT) deficiency. Newborn screening and early treatment do not completely prevent tremor, speech deficits, and diminished IQ in both sexes and premature ovarian insufficiency (POI) in women. Data on how individuals with galactosemia fare as adults will improve our ability to predict disease progression.METHODS: Thirty-three adults (mean age = 32.6 ± 11.7 years; range = 18-59) with classic galactosemia, confirmed by genotype and undetectable GALT enzyme activity, were evaluated. Analyses assessed associations among age, genotype, clinical features and laboratory measures.RESULTS: The sample included 17 men and 16 women. Subjects exhibited cataracts (21%), low bone density (24%), tremor (46%), ataxia (15%), dysarthria (24%), and apraxia of speech (9%). Subjects reported depression (39%) and anxiety (67%). Mean full scale IQ was 88 ± 20, (range = 55-122). All subjects followed a dairy-free diet and 75-80% reported low intake of calcium and vitamin D. Mean height, weight and body mass were within established norms. All female subjects had been diagnosed with POI. One woman and two men had had children. Logistic regression analyses revealed no associations between age, genotype or gender with IQ, tremor, ataxia, dysarthria, apraxia of speech or anxiety. Each 10- year increment of age was associated with a twofold increase in odds of depression.CONCLUSIONS: Taken together, these data do not support the hypothesis that galactosemia is a progressive neurodegenerative disease. However, greater attention to depression, anxiety, and social relationships may relieve the impact of this disorder in adults.

An initial stage of speech production is conceptual planning, where a speaker determines which information to convey first (the linearization problem). This fMRI study investigated the linearization process during the production of “before” and “after” sentences. In “after” sentences, a series of events is expressed in the order of event occurrence. In “before” sentences, however, the order of event mention is achieved by reversing the chronological order. We suggested that the linearization process may be supported by a neural network connecting the left middle temporal gyrus (MTG) with the medial superior frontal gyrus, left middle frontal gyrus, and left angular gyrus/inferior parietal gyrus. Within this network, regions were more activated and interregional interactions were strongly enhanced for producing “before” than “after” sentences. The left MTG was also functionally connected with the left orbital inferior frontal gyrus, contributing to the retrieval of necessary world knowledge and linguistic knowledge. Connectivity between these two regions was not different between conditions.

Recent evidence indicates that attention is higher for individually tailored as compared to non-tailored health communications. The present study examined whether the predicted increased attention for the tailored as opposed to general nutrition education messages is moderated by presenting high vs. low threat information about the negative consequences of an unhealthy diet. In a mixed subject experimental design, undergraduate students (N=34) were reading tailored and non-tailored nutrition education messages with either high or low threat information about the negative consequences of an unhealthy diet. At the same time, they had to pay attention to specific odd auditory stimuli in a sequence of frequent auditory stimuli (oddball paradigm). The amount of attention allocation was measured by recording event-related potentials (ERPs; i.e., N100, MMN, P300) and reaction times. Result revealed main effects of tailoring and threat, indicating that more attention resources were allocated to tailored vs. non-tailored messages and to low threat vs. high threat messages. The findings confirm that tailoring is an effective means to draw attention to health messages, whereas threat information seems to result in a loss in message attention.

Ignoring and selecting relevant faces has a strong impact in everyday life. We often perform tasks where faces may be considered irrelevant (e.g. having a drink in a crowded bar) or tasks where we need to filter out all but one face (e.g. searching for a friend in a crowd). The present study was designed to test Biased Competition (BC) as a suitable model for selection in the context of face processing, using functional magnetic resonance imaging (fMRI). Pairs of similar or dissimilar faces were presented simultaneously, and subjects had to attend to one face (target face) or ignore both faces. According to the BC model, faces simultaneously presented compete for representation. Spatial attention biases these competitive interactions towards neural processing of the target face only. We compared fMRI signal changes related to the processing of dissimilar or similar faces in the attend-to-face and ignore-faces task. In the ignore condition we expected that similar faces would compete more than dissimilar faces as similar features (faces) are supposed to be encoded by the same population of neurons resulting in a lower fMRI signal change in face selective areas. The BC model also predicts an enhancement of the fMRI signal change for attend-to-face vs. ignore-faces condition, regardless of the degree of the similarity between the two faces. Both hypotheses were confirmed by the data, indicating BC as a possible selection mechanism within the fusiform face area (FFA) and occipital face area (OFA) for face stimuli.

Objective: Previous studies indicate that people respond defensively to threatening health information, especially when the information challenges self-relevant goals. The authors investigated whether reduced acceptance of self-relevant health risk information is already visible in early attention processes, that is, attention disengagement processes. Design: In a randomized, controlled trial with 29 smoking and nonsmoking students, a variant of Posner's cueing task was used in combination with the high-temporal resolution method of event-related brain potentials (ERPs). Main Outcome Measures: Reaction times and P300 ERP. Results: Smokers showed lower P300 amplitudes in response to high- as opposed to low-threat invalid trials when moving their attention to a target in the opposite visual field, indicating more efficient attention disengagement processes. Furthermore, both smokers and nonsmokers showed increased P300 amplitudes in response to the presentation of high- as opposed to low-threat valid trials, indicating threat-induced attention-capturing processes. Reaction time measures did not support the ERP data, indicating that the ERP measure can be extremely informative to measure low-level attention biases in health communication. Conclusion: The findings provide the first neuroscientific support for the hypothesis that threatening health information causes more efficient disengagement among those for whom the health threat is self-relevant. (PsycINFO Database Record (c) 2010 APA, all rights reserved) (journal abstract)

Introduction Activation of neuronal networks is typically associated with a change in spectral power in electric signals within the network. The role of different spectral bands in mediating cognitive processes is still not fully understood. In human language networks, a hierarchical model has been suggested in which different types of linguistic information is transferred in different oscillatory bands. Within that model, attention is assumed to correlate with increase in gamma and decrease in alpha band power. Electrocorticography (ECoG) allows the segregation of neural representations independently of stimulus variation. Aim of the study Here, for the first time, we investigate whether selective attention to the different components of a syllable (i.e., consonants or vowels) modulates the spectral power of oscillatory activity (i.e., broadband gamma and alpha) and whether these changes relate to behavioral performance. Methods To address this issue, we measured ECoG signals in 11 patients with refractory epilepsy who were undergoing pre-surgical screening. Neuronal responses were measured with intracranial electrodes (i.e., grids, strips, and depth hippocampal electrodes). The patients engaged in cognitive testing in which auditory consonant–vowel syllable sounds were compared with written letters (i.e., delay match-to-sample task). The behavioral relevance of different components of the syllables was manipulated in four levels; attention was directed either to the complete syllable, only to the vowel, only to the consonant, or the syllable sound was irrelevant. Analysis We calculated: (a) bipolar differentials between each pair of neighboring channels; (b) time–frequency representations of power between 2 and 150 Hz; (c) an index of power change, per trial, relative to power during pre-stimulus baseline period; and (d) average power modulation for two frequency bands (i.e., 5–15 and 70–150 Hz). Results Presentation of stimuli was associated with an increase in broadband gamma (70–150 Hz) and a decrease in alpha (5–15 Hz) over sensory cortex (i.e., auditory cortex for auditory stimuli, and visual cortex for visual stimuli), while alpha power was increased in domain unspecific cortical areas. Gamma band activity could be robustly mapped to stimulus parameters but was only weakly related to attentional state or behavioral performance. Alpha band activity was more related to cognitive state and performance than to stimulus features. Broadband gamma power changes were related to stimulus physical properties. Conclusion These results give new insights into the interplay between alpha and gamma oscillations within the human language network, here with a focus on phonological aspects, and the possible role of these oscillations in the processing of sensory stimuli and behavioral performance during selective attention.

We investigated the processing of derived adjectives in German using event-related potentials (ERPs). ERPs were registered to existing adjectives (freundlich, ‘friendly’), to morphologically complex pseudowords that were synonymous to an existing adjective and thus interpretable (*freundhaft), and to complex pseudowords that were structurally and semantically anomalous (*freundbar). Stimuli were embedded in sentence contexts, displayed word by word. An ERP effect with a left-frontal maximum was observed around 450–500 ms after stimulus onset. In this window, both pseudoword types differed from existing adjectives. We interpret this data pattern as a LAN, reflecting structural problems due to morphological parsing, a process that is distinct from semantic processing.

Emotion is usually not discussed as a relevant variable in rational models of decision making—but may be one. The present electroencephalographic study demonstrates the influence of emotional primes (angry, happy faces) on purchase decisions. In a within-subject design, pictures of an apartment were shown to participants who then had to make Go/NoGo decisions on whether to rent it. Their decision should be based either on its price or on its brightness. In two thirds of the trials, emotional prime pictures of happy versus unhappy faces preceded the purchase target (apartment); in one third of the trials no prime was given. Response certainty was evaluated by means of reaction times (RT) and peak amplitude of the event-related potential N200. Facial primes accelerated decisions (RT) irrespective of affective expression. Positive face primes elicited larger N200 amplitudes during purchase decision compared to negative ones. Price-based decisions were made faster and elicited larger N200 than brightnessbased decisions. These results support the cognitive-tuning model of decision making and validate the N200 as sensitive measure for the interplay of cognitive and affective aspects in decision making.

Event-related potentials were used to investigate the interaction of verbal working memory and gender information during pronoun resolution. Gender information is supposed to be disentangled using sentences about persons (semantic/syntactic) or things (syntactic) followed by gender congruent or incongruent pronouns. Memory was manipulated using differential distances (short distance (SD) and long distances with or without intermediate subject gaps (LD gap and LD no gap)) between the pronoun and the antecedent. Comparing incongruent to congruent conditions, person sentences with SD and LD no gap resulted in an N400-like effect indicating the involvement of semantic integration, whereas a P600 effect in LD gap (re-activated antecedents) sentences suggested the involvement of syntactic reanalysis. SD-thing sentences showed a P600 effect, whereas LD thing sentences revealed no effect at pronoun position. A delayed N400 effect for thing sentences was observed instead. Based on preceding and the current data, we present a working model on how the parser switches between the use of semantic and syntactic information to establish co-reference and how this switch depends on the type of antecedent, distance, or syntactic structure.

Event-related potentials were used to study whether factors known to influence subject-verb number agreement in production exert analogous effects on sentence comprehension. Participants read Dutch sentences containing subject-verb number agreement errors while their brainwaves were measured. The determiner of the singular head noun could be ambiguous or unambiguous in number and the modifier ("local") noun could be plural or singular. Both ambiguity and number match affect error rates in production. We expected evoked potentials in response to the verb to be modulated by number ambiguity; larger effects were expected when the sentences started with an unambiguous determiner. When the local noun was singular, we observed a more negative wave elicited by the incorrect verbs compared to the correct verbs in the 350-400 ms time-window. This effect was largest when the head noun phrase contained no number ambiguity. When the local noun was plural the waves were more positive for incorrect verbs than for correct verbs in the 600-650 ms time-window. Again this effect was largest when the head noun phrase contained no number ambiguity. Most importantly, the results show that agreement computation in comprehension is influenced by the same factors as in production. We further suggest that in the sentences with a singular local noun there is a shallow analysis of the sentence, but the sentences with a plural local noun require a deeper syntactic analysis.

We report an event-related potential study investigating the neural basis of interference and facilitation in the picture-word interference paradigm with immediate overt naming. We used the high temporal resolution of the electrophysiological response to dissociate general and specific interference processes, by comparing unrelated word distractors to nonlinguistic (a row of Xs), surface feature denoting, and category member distractors. Our results first indicate that the increased naming latencies for linguistic relative to nonlinguistic distractors are because of general conflict-monitoring processes, associated with early event-related potential effects (120-220 ms) and increased activity in the anterior cingulate cortex. Next, distractors specifying a surface feature of the picture seem to facilitate its identification within the same time window, which involves widespread networks. Finally, nonlinguistic and surface feature distractors also reduced the N400 amplitude, relative to unrelated word distractors. Taken together our results support the view that several distinct processes give rise to the reaction time results often observed in picture naming.

In psycholinguistics, the coactivation of lexical candidates by partial input has received a lot of attention. More recently, psychophysiological studies have shed more light on this issue and identified two possible time windows in which effects of coactivation of lexical candidates can be observed in event-related potentials (ERPs). However, these studies cannot be used to disentangle effects of coactivation from the inhibition of candidates that do not match input. A new visual gating paradigm is presented, in which stimuli were visually presented letter by letter, decreasing the size of the cohort of lexical candidates as more letters are presented. Stimuli were created such that at the letter position of interest, the amount of coactivated candidates was kept constant while manipulating the size of the reduction of the cohort. The resulting ERPs indicate two components (frontal P2, and a left temporal late negativity) that scaled with cohort-size reduction. These results show that a visual gating paradigm can be used to disentangle coactivation of lexical candidates from inhibition of non-matching items, and that these processes are closely related to each other in time.

Speech production is an extremely rapid and seemingly effortless process with speech errors in normal subjects being rare. Although psycholinguistic models incorporate elaborate monitoring mechanisms to prevent and correct errors, the brain regions involved in their commitment, detection, and correction have remained elusive. Using event-related brain potentials in a task known to elicit spoonerisms representing a special class of sound errors, we show specific brain activity prior to the vocalization of such spoonerisms. Source modeling localized this activity to the supplementary motor area in medial frontal cortex. We propose that this activity reflects the simultaneous activation of 2 competing speech plans on processing levels related to the construction of a rather "phonetic" speech plan contrasting with the traditional view, assuming the substitution of abstract phonological representations as the main source for sound errors.

Patients with the inherited metabolic disorder classic galactosemia have language production impairments in several planning stages. Here, we assessed potential deviations in recruitment and connectivity across brain areas responsible for language production that may explain these deficits. We used functional magnetic resonance imaging (fMRI) to study neural activity and connectivity while participants carried out a language production task. This study included 13 adolescent patients and 13 age- and gender-matched healthy controls. Participants passively watched or actively described an animated visual scene using two conditions, varying in syntactic complexity (single words versus a sentence). Results showed that patients recruited additional and more extensive brain regions during sentence production. Both groups showed modulations with syntactic complexity in left inferior frontal gyrus (IFG), a region associated with syntactic planning, and in right insula. In addition, patients showed a modulation with syntax in left superior temporal gyrus (STG), whereas the controls did not. Further, patients showed increased activity in right STG and right supplementary motor area (SMA). The functional connectivity data showed similar patterns, with more extensive connectivity with frontal and motor regions, and restricted and weaker connectivity with superior temporal regions. Patients also showed higher baseline cerebral blood flow (CBF) in right IFG and trends towards higher CBF in bilateral STG, SMA and the insula. Taken together, the data demonstrate that language abnormalities in classic galactosemia are associated with specific changes within the language network. These changes point towards impairments related to both syntactic planning and speech motor planning in these patients. (C) 2015 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.

The brain's circuitry for perceiving and producing speech may show a notable level of overlap that is crucial for normal development and behavior. The extent to which sensorimotor integration plays a role in speech perception remains highly controversial, however. Methodological constraints related to experimental designs and analysis methods have so far prevented the disentanglement of neural responses to acoustic versus articulatory speech features. Using a passive listening paradigm and multivariate decoding of single-trial fMRI responses to spoken syllables, we investigated brain-based generalization of articulatory features (place and manner of articulation, and voicing) beyond their acoustic (surface) form in adult human listeners. For example, we trained a classifier to discriminate place of articulation within stop syllables (e.g., /pa/ vs /ta/) and tested whether this training generalizes to fricatives (e.g., /fa/ vs /sa/). This novel approach revealed generalization of place and manner of articulation at multiple cortical levels within the dorsal auditory pathway, including auditory, sensorimotor, motor, and somatosensory regions, suggesting the representation of sensorimotor information. Additionally, generalization of voicing included the right anterior superior temporal sulcus associated with the perception of human voices as well as somatosensory regions bilaterally. Our findings highlight the close connection between brain systems for speech perception and production, and in particular, indicate the availability of articulatory codes during passive speech perception.SIGNIFICANCE STATEMENTSensorimotor integration is central to verbal communication and provides a link between auditory signals of speech perception and motor programs of speech production. It remains highly controversial, however, to what extent the brain's speech perception system actively uses articulatory (motor), in addition to acoustic/phonetic, representations. In this study, we examine the role of articulatory representations during passive listening using carefully controlled stimuli (spoken syllables) in combination with multivariate fMRI decoding. Our approach enabled us to disentangle brain responses to acoustic and articulatory speech properties. In particular, it revealed articulatory-specific brain responses of speech at multiple cortical levels, including auditory, sensorimotor, and motor regions, suggesting the representation of sensorimotor information during passive speech perception.

White matter abnormalities have been observed in patients with classic galactosemia, an inborn error of galactose metabolism. However, magnetic resonance imaging (MRI) data collected in the past were generally qualitative in nature. Our objective was to investigate white matter microstructure pathology and examine correlations with outcome and behaviour in this disease, by using multi-shell diffusion weighted imaging. In addition to standard diffusion tensor imaging (DTI), neurite orientation dispersion and density imaging (NODDI) was used to estimate density and orientation dispersion of neurites in a group of eight patients (aged 16-21 years) and eight healthy controls (aged 15-20 years). Extensive white matter abnormalities were found: neurite density index (NDI) was lower in the patient group in bilateral anterior areas, and orientation dispersion index (ODI) was increased mainly in the left hemisphere. These specific regional profiles are in agreement with the cognitive profile observed in galactosemia, showing higher order cognitive impairments, and language and motor impairments, respectively. Less favourable white matter properties correlated positively with age and age at onset of diet, and negatively with behavioural outcome (e.g. visual working memory). To conclude, this study provides evidence of white matter pathology regarding density and dispersion of neurites in these patients. The results are discussed in light of suggested pathophysiological mechanisms.

An event-related brain potentials (ERP) experiment was carried out to investigate the influence of semantic category membership on syntactic decision-making. Native speakers of German viewed a series of words that were semantically marked or unmarked for gender and made go/no-go decisions about the grammatical gender of those words. The electrophysiological results indicated that participants could make a gender decision earlier when words were semantically gender-marked than when they were semantically gender-unmarked. Our data provide evidence for the influence of semantic category membership on the decision of the syntactic gender of a visually presented German noun. More specifically, our results support models of language comprehension in which semantic information processing of words is initiated prior to syntactic information processing is finalized.

The authors tested whether individually tailored health communications receive more attention from the reader than nontailored health communications in a randomized, controlled trial among student volunteers (N = 24). They used objective measures of attention allocation during the message exposure. In a between-subjects design, participants had to read tailored or nontailored nutrition education messages and at the same time had to pay attention to specific odd auditory stimuli in a sequence of frequent auditory stimuli (odd ball paradigm). The amount of attention allocation was measured by recording event-related potentials (ERPs; i.e., N100 and P300 ERPs) and reaction times. For the tailored as opposed to the nontailored group, results revealed larger amplitudes for the N 100 effect, smaller amplitudes for the P300 effect, and slower reaction times. Resource allocation theory and these results suggest that those in the tailored group allocated more attention resources to the nutrition message than those in the nontailored group.

Contains fulltext : 42649-OA.pdf (Publisher’s version ) (Open Access) German pronouns (erMALE/masculine, sieFEMALE/feminine) that refer to a person are determined by the biological gender (MALE/FEMALE) and/or syntactic gender (masculine/feminine) of the person. Pronouns (ermasculine, siefeminine) that refer to a thing are determined by the syntactic gender of this thing (Garten [garden]masculine, Tasche [hand-bag]feminine). The study aimed to investigate whether semantic integration, syntactic integration, or both are involved in establishing co-reference between pronoun and subject/antecedent in sentences. Here we focused on two event-related potential components: the SPS/P600, related to syntactic violation and reanalysis, and the N400 component, related to semantic integration problems. In one condition, a person was introduced as antecedent and later referred to by a pronoun, which either agreed in biological/syntactic gender or not (biological/syntactic gender violation). In a second condition, a thing was introduced as antecedent and the corresponding pronoun either agreed in syntactic gender or not (syntactic gender violation). Results at critical pronouns showed a P600 effect for incongruent compared with congruent pronouns in both conditions with a centro-parietal maximum. This effect was larger for the person compared to the thing condition. We interpreted this finding as reflecting a syntactic integration process that can be influenced by conceptual/semantic and syntactic information of the antecedent type. Furthermore, at the word following the pronoun, we observed an N400 for the thing but not for the person condition. We suggest, supported by the results of a control experiment, that this effect reflects continuous integration processes for things, whereas for persons the integration seems to be finished at pronoun position. 13 p.

This study investigated the time course of phonological encoding during speech production planning. Previous research has shown that conceptual/semantic information precedes syntactic information in the planning of speech production and that syntactic information is available earlier than phonological information. Here, we studied the relative time courses of the two different processes within phonological encoding, i.e. metrical encoding and syllabification. According to one prominent theory of language production, metrical encoding involves the retrieval of the stress pattern of a word, while syllabification is carried out to construct the syllabic structure of a word. However, the relative timing of these two processes is underspecified in the theory. We employed an implicit picture naming task and recorded event-related brain potentials to obtain fine-grained temporal information about metrical encoding and syllabification. Results revealed that both tasks generated effects that fall within the time window of phonological encoding. However, there was no timing difference between the two effects, suggesting that they occur approximately at the same time.

Bilinguals derive the same semantic concepts from equivalent, but acoustically different, words in their first and second languages. The neural mechanisms underlying the representation of language-independent concepts in the brain remain unclear. Here, we measured fMRI in human bilingual listeners and reveal that response patterns to individual spoken nouns in one language (e.g., “horse” in English) accurately predict the response patterns to equivalent nouns in the other language (e.g., “paard” in Dutch). Stimuli were four monosyllabic words in both languages, all from the category of “animal” nouns. For each word, pronunciations from three different speakers were included, allowing the investigation of speaker-independent representations of individual words. We used multivariate classifiers and a searchlight method to map the informative fMRI response patterns that enable decoding spoken words within languages (within-language discrimination) and across languages (across-language generalization). Response patterns discriminative of spoken words within language were distributed in multiple cortical regions, reflecting the complexity of the neural networks recruited during speech and language processing. Response patterns discriminative of spoken words across language were limited to localized clusters in the left anterior temporal lobe, the left angular gyrus and the posterior bank of the left postcentral gyrus, the right posterior superior temporal sulcus/superior temporal gyrus, the right medial anterior temporal lobe, the right anterior insula, and bilateral occipital cortex. These results corroborate the existence of “hub” regions organizing semantic-conceptual knowledge in abstract form at the fine-grained level of within semantic category discriminations.

During sentence production, linguistic information (semantics, syntax, phonology) of words is retrieved and assembled into a meaningful utterance. There is still debate on how we assemble single words into more complex syntactic structures such as noun phrases or sentences. In the present study, event-related potentials (ERPs) were used to investigate the time course of syntactic planning. Thirty-three volunteers described visually animated scenes using naming formats varying in syntactic complexity: from simple words ('W', e.g., "triangle", "red", "square", "green", "to fly towards"), to noun phrases ('NP', e.g., "the red triangle", "the green square", "to fly towards"), to a sentence ('S', e.g., "The red triangle flies towards the green square."). Behaviourally, we observed an increase in errors and corrections with increasing syntactic complexity, indicating a successful experimental manipulation. In the ERPs following scene onset, syntactic complexity variations were found in a P300-like component ('S'/'NP'>'W') and a fronto-central negativity (linear increase with syntactic complexity). In addition, the scene could display two actions - unpredictable for the participant, as the disambiguation occurred only later in the animation. Time-locked to the moment of visual disambiguation of the action and thus the verb, we observed another P300 component ('S'>'NP'/'W'). The data show for the first time evidence of sensitivity to syntactic planning within the P300 time window, time-locked to visual events critical of syntactic planning. We discuss the findings in the light of current syntactic planning views. © 2013 Timmers et al.

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.

Imagination is a key function for many human activities, such as reminiscing, learning, or planning. Unravelling its neuro-biological basis is paramount to grasp the essence of our thoughts. Previous neuroimaging studies have identified brain regions subserving the visualisation of "what?" (e.g. faces or objects) and "where?" (e.g. spatial layout) content of mental images. However, the functional role of a common set of involved regions - the frontal regions - and their interplay with the "what" and "where" regions, has remained largely unspecified. This study combines functional MRI and electroencephalography to examine the full-brain network that underlies the visual imagery of complex scenes and to investigate the spectro-temporal properties of its nodes, especially of the frontal cortex. Our results indicate that frontal regions integrate the "what" and "where" content of our thoughts into one visually imagined scene. We link early synchronisation of anterior theta and beta oscillations to regional activation of right and central frontal cortices, reflecting retrieval and integration of information. These frontal regions orchestrate remote occipital-temporal regions (including calcarine sulcus and parahippocampal gyrus) that encode the detailed representations of the objects, and parietal "where" regions that encode the spatial layout into forming one coherent mental picture. Specifically the mesial superior frontal gyrus appears to have a principal integrative role, as its activity during the visualisation of the scene predicts subsequent performance on the imagery task.

Previous studies indicate that people respond defensively to threatening health information, especially when the information challenges self-relevant goals. The authors investigated whether reduced acceptance of self-relevant health risk information is already visible in early attention allocation processes. In two experimental studies, participants were watching high- and low-threat health commercials, and at the same time had to pay attention to specific odd auditory stimuli in a sequence of frequent auditory stimuli (odd ball paradigm). The amount of attention allocation was measured by recording event-related brain potentials (i.e., P300 ERPs) and reaction times. Smokers showed larger P300 amplitudes in response to the auditory targets while watching high-threat instead of low-threat anti-smoking commercials. In contrast, non-smokers showed smaller P300 amplitudes during watching high as opposed to low threat anti-smoking commercials. In conclusion, the findings provide further neuroscientific support for the hypothesis that threatening health information causes more avoidance responses among those for whom the health threat is self-relevant.