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Objective: Hippocampal inflammation in anti-LGI1 encephalitis causes memory deficits, seizures and behavioural abnormalities. Recent findings suggest that extralimbic brain areas are additionally affected and that patients also suffer from non-limbic cognitive symptoms. Moreover, up to 60% of patients show no structural MRI abnormalities in the acute disease stage. We therefore investigated whether functional connectivity analyses can identify brain network changes underlying disease-related symptoms., Methods: We studied 27 patients and a matched healthy control group using structural and functional MRI. Intrinsic functional networks were analysed using Independent Component Analysis and Dual Regression. Cognitive testing covered working memory, episodic memory, attention and executive function., Results: Our analysis revealed functional connectivity alterations in several large-scale networks, including the default mode network (DMN) which showed an aberrant structure-function relationship with the damaged hippocampus. In addition, connectivity in the sensorimotor, salience and higher visual networks was impaired independent of hippocampal damage. Increased connectivity in ventral and dorsal DMN regions significantly correlated with better memory performance. In contrast, stronger connectivity of the insula with the salience network and DMN was linked to impaired memory function., Conclusions: Anti-LGI1 encephalitis is associated with a characteristic pattern of widespread functional network alterations. Increased DMN connectivity seems to represent a compensatory mechanism for memory impairment induced by hippocampal damage. Network analyses may provide a key to the understanding of clinical symptoms in autoimmune encephalitis and reveal changes of brain function beyond apparent structural damage., Competing Interests: Competing interests: FP and TB report personal fees outside the submitted work. None declared for all other authors., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Novel rehabilitation interventions have improved motor recovery by induction of neural plasticity in individuals with stroke. Of these, Music-supported therapy (MST) is based on music training designed to restore motor deficits. Music training requires multimodal processing, involving the integration and co-operation of visual, motor, auditory, affective and cognitive systems. The main objective of this study was to assess, in a group of 20 individuals suffering from chronic stroke, the motor, cognitive, emotional and neuroplastic effects of MST. Using functional magnetic resonance imaging (fMRI) we observed a clear restitution of both activity and connectivity among auditory-motor regions of the affected hemisphere. Importantly, no differences were observed in this functional network in a healthy control group, ruling out possible confounds such as repeated imaging testing. Moreover, this increase in activity and connectivity between auditory and motor regions was accompanied by a functional improvement of the paretic hand. The present results confirm MST as a viable intervention to improve motor function in chronic stroke individuals.

Introduction: A clustering of relatives with dystonia has been reported in families with musician's dystonia suggesting a genetic contribution to this disease. The aim of the present study was to determine whether interhemispheric inhibition (IHI) measured with transcranial magnetic stimulation is impaired in healthy family members rendering it a suitable endophenotypic marker for musician's dystonia., Methods: Patients with musician's hand dystonia (n = 21), patients with sporadic writer's cramp (n = 15), their healthy family members (n = 27), healthy musicians (n = 12) and healthy non-musicians (n = 12) were included. An extended interview about the family history and musical activity was performed. IHI in both hemispheres was measured using transcranial magnetic stimulation., Results: A stepwise regression analysis revealed musical activity (p = 0.001) and a family history of dystonia (p = 0.008) but not dystonia per se, age, handedness or gender as relevant factors modulating IHI., Conclusion: These data support the notion of a genetic background of musician's hand dystonia and suggests that reduced IHI is a possible endophenotypic marker of this disorder., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

We investigated phonological processing in normal readers to answer the question to what extent phonological recoding is active during silent reading and if or how it guides lexico-semantic access. We addressed this issue by looking at pseudohomophone and baseword frequency effects in lexical decisions with event-related functional magnetic resonance imaging (fMRI). The results revealed greater activation in response to pseudohomophones than for well-controlled pseudowords in the left inferior/superior frontal and middle temporal cortex, left insula, and left superior parietal lobule. Furthermore, we observed a baseword frequency effect for pseudohomophones (e.g., FEAL) but not for pseudowords (e.g., FEEP). This baseword frequency effect was qualified by activation differences in bilateral angular and left supramarginal, and bilateral middle temporal gyri for pseudohomophones with low- compared to high-frequency basewords. We propose that lexical decisions to pseudohomophones involves phonology-driven lexico-semantic activation of their basewords and that this is converging neuroimaging evidence for automatically activated phonological representations during silent reading in experienced readers., (Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The present study used event-related brain potentials (ERPs) to investigate audiovisual integration processes in the perception of natural speech in a group of German adult developmental dyslexic readers. Twelve dyslexic and twelve non-dyslexic adults viewed short videos of a male German speaker. Disyllabic German nouns served as stimulus material. The auditory and the visual stimulus streams were segregated to create four conditions: in the congruent condition, the spoken word and the auditory word were identical. In the incongruent condition, the auditory and the visual word (i.e., the lip movements of the utterance) were different. Furthermore, on half of the trials, white noise (45 dB SPL) was superimposed on the auditory trace. Subjects had to say aloud the word they understood after they viewed the video. Behavioral data. Dyslexic readers committed more errors compared to normal readers in the noise conditions, and this effect was particularly present for congruent trials. ERPs showed a distinct N170 component at temporo-parietal electrodes that was smaller in amplitude for dyslexic readers. Both, normal and dyslexic readers, showed a clear effect of noise at centro-parietal electrodes between 300 and 600 ms. An analysis of error trials reflecting audiovisual integration (verbal responses in the incongruent noise condition that are a mix of the visual and the auditory word) revealed more positive ERPs for dyslexic readers at temporo-parietal electrodes 200-500 ms poststimulus. For normal readers, no such effect was present. These findings are discussed as reflecting increased effort in dyslexics under circumstances of distorted acoustic input. The superimposition of noise leads dyslexics to rely more on the integration of auditory and visual input (lip reading). Furthermore, the smaller N170-amplitudes indicate deficits in the processing of moving faces in dyslexic adults., (Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.)

Despite significant advances, the neural correlates and neurochemical mechanisms involved in performance monitoring and behavioral adaptation are still a matter for debate. Here, we used a modified Eriksen-Flanker task in a magnetic resonance imaging (MRI) study that required the participants to derive the correct stimulus-response association based on a feedback given after each flanker stimulus. Participants had to continuously monitor and adapt their performance as the stimulus-response association switched after a jittered time interval without notice. After every switch an increase of reaction times was observed. At the neural level, the feedback indicating the need to switch was associated with activation of the precuneus, the cingulate cortex, the insula and a brainstem region tentatively identified as the locus coeruleus. This brainstem system appears to interact with this cortical network and seems to be essential for performance monitoring and behavioral adaptation. In contrast, the cerebellum crus and prefrontal areas are activated during error feedback processing. Furthermore we found activations of the hippocampus and parahippocampal gyrus bilaterally after a correct feedback in learnable stimulus-response associations. These results highlight the contribution of brainstem nuclei to performance adaptation., (Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.)

Speech perception is an essential part of social interaction. Visual information (lip movements, facial expression) may supplement auditory information in particular under inadvertent listening situations. Schizophrenia patients have been shown to have a deficit in integrating articulatory motions with the auditory speech input. The goal of this study was to investigate the neural basis of this deficit in audiovisual speech processing in schizophrenia patients by using fMRI. Disyllabic nouns were presented in congruent (audio matches visual information) and incongruent conditions in a slow event related fMRI design. Schizophrenia patients (n=15) were compared to age and gender matched control participants. The statistical examination was conducted by analysis of variance with main factors: audiovisual congruency and group membership. The patients' brain activity differed from the control group as evidenced by congruency by group interaction effects. The pertinent brain sites were located predominantly in the right hemisphere and comprised the pars opercularis, middle frontal sulcus, and superior temporal gyrus. In addition, we observed interactions bilaterally in the fusiform gyrus and the nucleus accumbens. We suggest that schizophrenia patients' deficits in audiovisual integration during speech perception are due to a dysfunction of the speech motor system in the right hemisphere. Furthermore the results can be also seen as a reflection of reduced lateralization of language functions to the left hemisphere in schizophrenia.

Objective: Humans need to supervise and adjust their own behavior by means of an error detection and correction system as well as by using externally available information. The purpose of the present study was to compare the electrophysiological effects related to self-generated internal and to external (feedback) information used for performance monitoring., Methods: Fourteen young normal subjects learned to associate each of several line-drawings with either a left-hand or right-hand response. In the experiment proper multi-channel ERPs were obtained time-locked to (a) the line-drawings, (b) the button-press, and (c) subsequent feedback stimuli. Feedback was either affirmative, negative, or equivocal. Event-related potentials were quantified and statistically evaluated using standard methodology., Results: Response-locked ERPs showed a typical error-related negativity (ERN) for erroneous responses. ERPs to negative and equivocal feedback stimuli contained a negativity with a more posterior distribution than that of the ERN, which occurred earlier and had a higher peak amplitude in the equivocal condition. Dipole modeling suggests that this feedback-related negativity is generated by medial prefrontal and posterior cingulate cortex areas., Conclusions: Different brain systems support the use of internal and external information necessary for performance monitoring and modification., Significance: The flexible use of internal and external information for performance control is a core executive function. The delineation of the corresponding brain correlates will further our understanding of executive dysfunction in neurological disorders.

Neurocognitive involvement in multiple sclerosis (MS) is heterogeneous with some authors suggesting a frontal pattern in patients with predominantly frontal lesions. To assess the relationship between the distribution of lesions and two cognitive components (visual N2, auditory P3a) of the event-related brain potential (ERP) receiving contributions from frontal lobe structures, we performed a combined ERP and magnetic resonance imaging (MRI) study. Thirty-four MS patients were assigned to "low lesion volume, (LLV)"(n = 12),"high lesion volume,(HLV)"(n = 12) and"frontal lesion volume, (FLV)" (n = 10) groups according to lesion volume and distribution on T2-weighted MRI-scans of the brain. ERPs in visual and auditory classification tasks as well as neuropsychological tests were carried out in patients and control subjects (n = 15). The index for automatic feature registration, the N2 component with its mainly frontal contribution in the visual task, was significantly reduced in amplitude in the FLV and HLV groups (both p < 0.01 vs. controls). Moreover its amplitude correlated with lesion volume (r=0.64, p < 0.001). In contrast neither P3a nor P3b subcomponents with a multiple generator nature in the auditory task varied systematically with lesion volume or distribution. Total lesion volume rather than predominant lesion arrangement appears to be the most important factor in neurocognitive changes in MS. This is most consistent with the view that MS lesions lead to partial disconnections within widespread cortical networks which in turn produce a pattern of neuropsychological deficits that reflect total lesion load more than lesion distribution.

The ERP (event-related potential) violation paradigm was used to investigate brain responses to morphologically correct and incorrect verb forms of Catalan. Violations of stem formation and inflectional processes were examined in separate experimental conditions. Our most interesting finding is that misapplications of stem formation rules elicit an early left preponderant negativity. This complements our previous ERP results on morphological violations in other languages in which misapplications of inflectional rules were shown to produce such effects. We make use of the linguistic distinction between lexically stored and rule-based word forms and suggest a unified interpretation of the experimental results, arguing that these negativities vary as a function of processes involved in morpho-syntactic structure building.

Closed class (determiners, pronouns, conjunctions, prepositions etc. ) and open class (nouns, verbs, adjectives, adverbs) words have different linguistic functions and have been proposed to be processed by different neural systems. Here, event-related potentials (ERPs) were recorded in young German-speaking subjects while they read closed class and open class words flashed upon a video-screen. In the first experiment closed class words were sorted into four different frequency categories and open class words into three categories. The words were presented in a list with the subjects' task to detect occasional non-words. A centroparietal negativity (N400) with a peak latency of about 400 ms varied in amplitude as a function of frequency in both classes. The N400 in closed class items, however, was considerably smaller than that in open class words of similar frequency. A left anterior negativity (N280/LPN) showed some degree of frequency-sensitivity regardless of word class. Only for the very high frequency closed class words a frontal negativity with an onset of about 400 ms was obtained (N400-700). This N400-700 effect was replicated in the second study, in which medium frequency closed and open class words and very high frequency closed class words were presented at the fifth position of simple German sentences. It is suggested that neither N400 nor the left anterior negativity (N280/LPN) distinguish qualitatively between the two word classes and thus claims about different brain systems involved in the processing of open and closed class words are not substantiated electrophysiologically. The N400-700 effect is possibly related to specific grammatical functions of some closed class items, such as determiners.

In the present study we made use of Event-Related Potentials (ERPs) to examine raising and subject control constructions in German. Our most salient result is that the ERPs elicited at the empty subject position of a raising construction are clearly different from those elicited at the corresponding position of an otherwise identical subject control construction, the former producing a stronger P600. We argue that this result provides an electrophysiological correlate of the theoretical distinction between NP trace and PRO.

Objectives: Amyotrophic lateral sclerosis (ALS) has been shown to cause neuropsychological deficits. The present investigation sought to delineate memory deficits by recording cognitive event-related potentials (ERPs)., Subjects and Methods: Eight ALS patients and 8 matched controls were subjected to a 2-phase recognition memory test. During the first phase words were presented consecutively on a video-screen with one-third of the words being repeated. The subject had to press buttons according to whether a word had been repeated or not. During the second phase (delay 1 h) a second list containing 33% old items from phase 1 and 66% new words was shown with an old/new decision required., Results: ALS patients showed less accurate recognition in the second phase. The ERPs of the controls showed a reliable difference between old and new items in both phases. This difference was nearly absent in the patients in both phases., Conclusion: The ERP pattern suggests abnormal memory processes in ALS. The results are compared with data from similar experiments in Huntington's and Alzheimer's disease and are interpreted in terms of an encoding deficit in ALS.

One of the current issues in the investigation of language by means of event-related brain potentials (ERPs) is whether there is an ERP effect that can be specifically related to the processing of syntactic information. It has been claimed that a late positivity (P600 or SPS-syntactic positive shift) occurring to syntactic violations or ambiguities qualifies as such an effect. In the present investigation we compared ERPs elicited by morphosyntactic (case inflection errors), semantic, and orthographic (misspelled words) violations in a group of young German subjects. All three types of violations gave rise to late positivities having the characteristics of the previously described P600/SPS. In an earlier time window, however, semantic violations were associated with a centroparietally distributed N400 component, whereas syntactic violations gave rise to a negativity of smaller amplitude that had a frontocentral distribution. In light of the present experiment, the view that the P600/SPS as a whole reflects specific syntactic processes appears to be untenable and an alternative interpretation is proposed. The different distributions of the late positive shifts merit further investigation.

Event-related brain potentials (ERPs) were recorded from multiple scalp locations from young human subjects while they performed two different face processing tasks. The first task entailed the presentation of pairs of faces in which the second face was either a different view of the first face or a different view of a different face. The subjects had to decide whether or not the two faces depicted the same person. In the second task, pairs of faces (frontal views) were presented with the task of judging whether the expression of the second face matched that of the face. Incongruous faces in the view (identity) matching task gave rise to a negativity peaking at about 350 ms with a frontocentral maximum. This effect was similar to the N400 obtained in linguistic tasks. ERP effects in the expression matching task were much later and had a different distribution. This pattern of results corresponds well with neuropsychological and neuroimaging data suggesting specialized neuronal populations subserving identity and expression analysis but adds a temporal dimension to previous investigations.

In order to determine if an event-related brain potential (ERP) effect described for syntactic violations (P600/SPS) varies with the amount of reprocessing entailed by a violation, number incongruencies were presented either within simple declarative or within subordinate clauses. ERPs were recorded while 12 German subjects read the stimulus materials presented word by word on a video monitor. The ERPs showed a P600/SPS effect for all sentence types, which was smallest in amplitude and earliest in latency for simple declarative sentences. This effect therefore qualifies as a metric for the amount and timing of syntactic reprocessing entailed by a syntactic error. In addition, a late frontal negativity (1000-1400 ms range) was found for the simple declarative sentences.

Several parameters of the event-related potential (ERP) were assessed while 12 healthy volunteers performed a time production task. Each trial consisted of a series of 20 flashes presented at regular intervals on a videomonitor (interval 768 ms). After these flashes the subjects had to estimate the time it would take for an additional five flashes and to press a button upon the 5th interval. ERPs were recorded from 19 electrodes with three effects being of interest: (1) possible emitted potentials at the times at which flashes had occurred, if the series had continued, (2) the ERP to probe flashes presented during the production period, and (3) the slow potential shift during the estimation period. In addition reaction times were recorded. While ERP effects (1) and (2) were not informative with respect to time estimation processes, the slow potential shift with a frontopolar distribution appears to index time-keeping functions in humans.

The purpose of this study was to investigate electrophysiological correlates related to the recognition of repeated faces in the intact human by means of event-related brain potentials (ERPs). A group of young healthy adults performed a continuous face recognition task, in which 240 unfamiliar faces were flashed upon a computer screen with 80 of the faces being repetitions. The subjects had to classify faces as previously seen and previously unseen faces. The concomitantly recorded ERPs from 19 scalp sites revealed a more positive going waveform for the correctly classified repeated faces beginning at about 280 ms (old/new effect). The same subjects performed a similar task with visually presented concrete nouns as stimuli. The old/new effect in this task showed a similar distribution, amplitude and onset latency. It is thus concluded that the old/new effect is not specific to the materials to be memorized. In contrast, the old/new effect in an implicit face repetition experiment (with the detection of famous persons being the task) showed a different distribution. It is argued that the differential distribution might reflect the different requirements of the two tasks (explicit vs. implicit task). Recent interpretations of the old/new effects are discussed.

Event-related brain potentials were recorded as 18 German-speaking subjects read sentences that contained as critical words German nouns in correct and incorrect plural forms. Two types of plurals were investigated: regular -s plurals (e.g. Karussell-s 'roundabouts') and irregular -(e)n plurals (Muskel-n "muscles'). We compared correct regular and irregular plurals with incorrect ones; the latter had -(e)n on nouns that actually take -s plurals (*Karussell-en), or -s on nouns that require -(e)n (*Muskel-s). ERPs showed different responses to regular and irregular plurals: incorrect irregular plurals (*Muskel-s) elicited a ramp-shaped left frontotemporal negativity, whereas incorrect regulars (*Karussell-en) produced a central phasic negativity with a maximum at 380 ms. This dissociation supports the view that regularly inflected words are processed differently from irregularly inflected ones.

Event-related potentials (ERPs) were recorded from 16 native speakers of Turkish while they watched Turkish sentences flashed upon the screen of a videomonitor. The sentences were three words long and contained a verb at the terminal position that was manipulated (1) to have either the correct or the incorrect number with regard to the subject of the sentence, and (2) to be semantically appropriate, inappropriate or to be a pseudoverb. The ERPs from 19 scalp channels revealed a more positive waveform at the left-fronto-temporal site with an onset latency of about 200 ms for the verbs having the wrong number regardless of the semantic appropriateness of the word, while at right fronto-temporal sites a more negative waveform was observed for plural words only. This number incongruency ERP-effect in Turkish is clearly at odds with findings from other languages.

Objective: To delineate deficits in language processing after closed head injury with use of behavioral measures and event-related brain potentials., Design: Case-control design. All subjects participated in three verbal event-related brain potential experiments, and the resulting measures were compared both within and between groups. PATIENTS/CONTROLS: Eleven patients at least 2 years after severe closed head injury (Glasgow Coma Scale score < 8 at admission and duration of posttraumatic amnesia > 48 hours) were compared with a control group matched for age and educational level., Interventions: None., Main Outcome Measures: Reaction times and percentage correct as behavioral measures in the three experiments (sentence verification, semantic and repetition priming with lexical decision task, and continuous word recognition). Event-related brain potentials were quantified by area measures in successive time windows for the different experimental conditions and for different experiments., Results: The reaction times of the patient group were significantly longer than those of the controls (P < .005). Similarly, the patients' accuracy was significantly worse in all experiments (P < .03). The event-related brain potentials of the controls showed a clear and significant reduction of a negative component (N400) to terminal words of true sentences (sentence verification experiment), semantically primed words and repeated words (lexical decision experiment), and recognized words (continuous word recognition). For the patients, a clear N400 effect was seen only in the sentence verification task (delayed by about 100 milliseconds), while only later event-related brain potential modulations were seen in the other tasks., Conclusion: Language functions are disturbed after closed head injury. The electrophysiologic data suggest difficulties in the integration of incoming linguistic stimuli with the previous context as a possible underlying cause.

Although endogenous event-related potentials (ERPs) have been successfully used in psychology, they have largely been neglected in the study of psychotropic substances. In the present paper an overview is given of the diversified concepts of ERP research and useful adaptations of these approaches to psychopharmacological questions are shown. In particular, the influence of drugs on the various stages of information processing and the description of individual differences in drug reactions seem suitable for the use of endogenous ERPs. Other possible uses of ERPs in psychopharmacological research are briefly discussed and the problems of the technique are pointed out. It is concluded that future research should aim at the recording of 'ERP profiles' of a drug, monitoring pharmacological effects on the different levels of cognitive functions by a set of selected paradigms.