scholarly journals Symmetrical electrophysiological brain responses to unilateral and bilateral auditory stimuli suggest disrupted spatial processing in schizophrenia

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Sara Sardari ◽  
Ali Mohammad Pourrahimi ◽  
Hossein Talebi ◽  
Shahrzad Mazhari
Keyword(s):  
Mismatch Negativity ◽  
Event Related Potentials ◽  
Frequency Discrimination ◽  
Stimulus Location ◽  
Spatial Processing ◽  
Healthy Individuals ◽  
Brain Responses ◽  
Schizophrenic Patients ◽  
Related Potentials ◽  
Processing Deficits

Abstract Research has found auditory spatial processing deficits in patients with schizophrenia (SCZ), but no study has examined SCZ patients’ auditory spatial processing at both pre-attentional and attentional stages. To address this gap, we investigated schizophrenics’ brain responses to sounds originating from different locations (right, left, and bilateral sources). The event-related potentials (ERPs) of 25 chronic schizophrenic patients and 25 healthy subjects were compared. Mismatch negativity (MMN) in response to frequency and duration deviants was assessed. Two P3 components (P3a and P3b) were elicited via a frequency discrimination task, and MMN and P3 were recorded through separate monaural and dichotic stimulation paradigms. Our results corroborated the previously published finding that MMN, P3a, and P3b amplitudes are reduced in SCZ patients, but they showed no significant effect of stimulus location on either MMN or P3. These results indicated similarity between the SCZ patients and healthy individuals as regards patterns of ERP responses to stimuli that come from different directions. No evidence of auditory hemispatial bias in the SCZ patients was found, supporting the existence of non-lateralized spatial processing deficits in such patients and suggesting compensatory changes in the hemispheric laterality of patients’ brains.

Effects of Experimentally Induced Pain on Mismatch Negativity

2006 ◽  
Vol 20 (1) ◽  
pp. 21-31 ◽  
Author(s):  
Bruce D. Dick ◽  
John F. Connolly ◽  
Michael E. Houlihan ◽  
Patrick J. McGrath ◽  
G. Allen Finley ◽  
...  
Keyword(s):  
Cognitive Processing ◽  
Mismatch Negativity ◽  
Event Related Potentials ◽  
Disruptive Effect ◽  
Ischemic Pain ◽  
Active Attention ◽  
Early Processing ◽  
Related Potentials ◽  
Healthy Participants ◽  
Experimentally Induced

Abstract: Previous research has found that pain can exert a disruptive effect on cognitive processing. This experiment was conducted to extend previous research with participants with chronic pain. This report examines pain's effects on early processing of auditory stimulus differences using the Mismatch Negativity (MMN) in healthy participants while they experienced experimentally induced pain. Event-related potentials (ERPs) were recorded using target and standard tones whose pitch differences were easy- or difficult-to-detect in conditions where participants attended to (active attention) or ignored (passive attention) the stimuli. Both attention manipulations were conducted in no pain and pain conditions. Experimentally induced ischemic pain did not disrupt the MMN. However, MMN amplitudes were larger to difficult-to-detect deviant tones during painful stimulation when they were attended than when they were ignored. Also, MMN amplitudes were larger to the difficult- than to the easy-to-detect tones in the active attention condition regardless of pain condition. It appears that rather than exerting a disruptive effect, the presence of experimentally induced pain enhanced early processing of small stimulus differences in these healthy participants.

An ERP Investigation of Semantic Priming, Repetition Priming, and Negative Priming in Schizophrenic Patients

2006 ◽  
Vol 20 (3) ◽  
pp. 195-211 ◽  
Author(s):  
Michael Wagner ◽  
Lioba Baving ◽  
Patrick Berg ◽  
Rudolf Cohen ◽  
Brigitte Rockstroh
Keyword(s):  
Negative Priming ◽  
Repetition Priming ◽  
Event Related Potentials ◽  
Decision Task ◽  
Positive Priming ◽  
Retrieval Processes ◽  
Schizophrenic Patients ◽  
Related Potentials ◽  
Late Positive Complex ◽  
Automatic Memory

The processing of attended and nonattended stimuli in schizophrenic patients was examined with event-related potentials (ERPs) in a lexical decision task. In positive semantic and repetition priming the N400 amplitude did not differ between a group of 17 medicated schizophrenic patients and a group of 20 matched healthy controls. However, negative priming affected the N400 only in controls. Reaction time effects were dissociated from these ERP effects, with patients showing stronger positive priming than controls but identical negative priming. The semantic processes related to the N400 appear to be intact in schizophrenic patients, but patients seem to incorporate less context information (about the nonattended prime) in their episodic memory traces. A stronger increase of the posterior late positive complex in parallel to the stronger positive priming in schizophrenic patients may reflect relatively stronger automatic memory retrieval processes in patients.

Human Event-Related Potentials to Higher-Order Acoustic Spatial Changes

2002 ◽  
Vol 16 (2) ◽  
pp. 114-118 ◽  
Author(s):  
Timo Ruusuvirta ◽  
Heikki Hämäläinen
Keyword(s):  
Working Memory ◽  
Mismatch Negativity ◽  
Spatial Information ◽  
Free Field ◽  
Event Related Potentials ◽  
Negative Polarity ◽  
Positive Polarity ◽  
Spatial Changes ◽  
Related Potentials ◽  
Human Event

Abstract Human event-related potentials (ERPs) to a tone continuously alternating between its two spatial loci of origin (middle-standards, left-standards), to repetitions of left-standards (oddball-deviants), and to the tones originally representing these repetitions presented alone (alone-deviants) were recorded in free-field conditions. During the recordings (Fz, Cz, Pz, M1, and M2 referenced to nose), the subjects watched a silent movie. Oddball-deviants elicited a spatially diffuse two-peaked deflection of positive polarity. It differed from a deflection elicited by left-standards and commenced earlier than a prominent deflection of negative polarity (N1) elicited by alone-deviants. The results are discussed in the context of the mismatch negativity (MMN) and previous findings of dissociation between spatial and non-spatial information in auditory working memory.

scholarly journals Logatome Discrimination in Cochlear Implant Users: Subjective Tests Compared to the Mismatch Negativity

2010 ◽  
Vol 10 ◽  
pp. 329-339 ◽  
Author(s):  
Torsten Rahne ◽  
Michael Ziese ◽  
Dorothea Rostalski ◽  
Roland Mühler
Keyword(s):  
Speech Perception ◽  
Cochlear Implant ◽  
Mismatch Negativity ◽  
Speech Intelligibility ◽  
Event Related Potentials ◽  
Normal Hearing ◽  
Discrimination Test ◽  
Speech Database ◽  
Automated Speech Recognition ◽  
Related Potentials

This paper describes a logatome discrimination test for the assessment of speech perception in cochlear implant users (CI users), based on a multilingual speech database, the Oldenburg Logatome Corpus, which was originally recorded for the comparison of human and automated speech recognition. The logatome discrimination task is based on the presentation of 100 logatome pairs (i.e., nonsense syllables) with balanced representations of alternating “vowel-replacement” and “consonant-replacement” paradigms in order to assess phoneme confusions. Thirteen adult normal hearing listeners and eight adult CI users, including both good and poor performers, were included in the study and completed the test after their speech intelligibility abilities were evaluated with an established sentence test in noise. Furthermore, the discrimination abilities were measured electrophysiologically by recording the mismatch negativity (MMN) as a component of auditory event-related potentials. The results show a clear MMN response only for normal hearing listeners and CI users with good performance, correlating with their logatome discrimination abilities. Higher discrimination scores for vowel-replacement paradigms than for the consonant-replacement paradigms were found. We conclude that the logatome discrimination test is well suited to monitor the speech perception skills of CI users. Due to the large number of available spoken logatome items, the Oldenburg Logatome Corpus appears to provide a useful and powerful basis for further development of speech perception tests for CI users.

Brain Responses to World Knowledge Violations: A Comparison of Stimulus- and Fixation-triggered Event-related Potentials and Neural Oscillations

2015 ◽  
Vol 27 (5) ◽  
pp. 1017-1028 ◽  
Author(s):  
Paul Metzner ◽  
Titus von der Malsburg ◽  
Shravan Vasishth ◽  
Frank Rösler
Keyword(s):  
Word Meaning ◽  
Event Related Potentials ◽  
Visual Presentation ◽  
World Knowledge ◽  
N400 Effect ◽  
Brain Potentials ◽  
Time Frequency ◽  
Gamma Range ◽  
Brain Responses ◽  
Related Potentials

Recent research has shown that brain potentials time-locked to fixations in natural reading can be similar to brain potentials recorded during rapid serial visual presentation (RSVP). We attempted two replications of Hagoort, Hald, Bastiaansen, and Petersson [Hagoort, P., Hald, L., Bastiaansen, M., & Petersson, K. M. Integration of word meaning and world knowledge in language comprehension. Science, 304, 438–441, 2004] to determine whether this correspondence also holds for oscillatory brain responses. Hagoort et al. reported an N400 effect and synchronization in the theta and gamma range following world knowledge violations. Our first experiment (n = 32) used RSVP and replicated both the N400 effect in the ERPs and the power increase in the theta range in the time–frequency domain. In the second experiment (n = 49), participants read the same materials freely while their eye movements and their EEG were monitored. First fixation durations, gaze durations, and regression rates were increased, and the ERP showed an N400 effect. An analysis of time–frequency representations showed synchronization in the delta range (1–3 Hz) and desynchronization in the upper alpha range (11–13 Hz) but no theta or gamma effects. The results suggest that oscillatory EEG changes elicited by world knowledge violations are different in natural reading and RSVP. This may reflect differences in how representations are constructed and retrieved from memory in the two presentation modes.

scholarly journals Depressive rumination is correlated with brain responses during self-related processing

2021 ◽  
Author(s):  
Tzu-Yu Hsu ◽  
Tzu-Ling Liu ◽  
Paul Z. Cheng ◽  
Hsin-Chien Lee ◽  
Timothy J. Lane ◽  
...  
Keyword(s):  
Depressive Symptoms ◽  
Low Frequency ◽  
Event Related Potentials ◽  
Unipolar Depression ◽  
Brain Responses ◽  
Late Event ◽  
Oscillatory Power ◽  
Related Aspect ◽  
Related Potentials ◽  
Central Symptom

AbstractBackgroundRumination, a tendency to focus on negative self-related thoughts, is a central symptom of depression. Studying the self-related aspect of such symptoms is challenging due to the need to distinguish self effects per se from the emotional content of task stimuli. This study employs an emotionally neutral self-related paradigm to investigate possible altered self processing in depression and its link to rumination.MethodsPeople with unipolar depression (MDD; n = 25) and controls (n = 25) underwent task-based EEG recording. Late event-related potentials were studied along with low frequency oscillatory power. EEG metrics were compared between groups and correlated with depressive symptoms and reported rumination.ResultsThe MDD group displayed a difference in late potentials across fronto-central electrodes between self-related and non-self-related conditions. No such difference was seen in controls. The magnitude of this difference was positively related with depressive symptoms and reported rumination. MDD also had elevated theta oscillation power at central electrodes in self-related conditions, which was not seen in controls.ConclusionsRumination appears linked to altered self-related processing in depression, independently of stimuli-related emotional confounds. This connection between self-related processing and depression may point to self-disorder being a core component of the condition.

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