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Papers by Christian Wienbruch
International Journal of Psychophysiology, 2010
t.- .•..~ .....· .•...·. rr attributed to pathological or 'dysfunctional' neural tissue (... more t.- .•..~ .....· .•...·. rr attributed to pathological or 'dysfunctional' neural tissue (Niedermeyer and Lopes' da Silva, 1987; Lewine. and Orrison, 1995). Similar to the interpretation of~~Jow oscillatory rhythms,during sleep stages as deafferelltation of the cortex due to thalamic hyperpolarisation (Steriade, 1997), abnormal focal slow wave activity in the waking state miQ'ht indicate fUllctiollal deafferelltatioll in the sense of
BMC Psychiatry, 2005
BACKGROUND: The present study was dedicated to investigate the influence of Methylphenidate (MPH)... more BACKGROUND: The present study was dedicated to investigate the influence of Methylphenidate (MPH) on cortical processing of children who were diagnosed with different subtypes of Attention Deficit Hyperactivity Disorder (ADHD). As all of the previous studies investigating power differences in different frequency bands have been using EEG, mostly with a relatively small number of electrodes our aim was to obtain
Biological Psychiatry, 2001
Background: Schizophrenic patients exhibit more activity in the electroencephalographic delta and... more Background: Schizophrenic patients exhibit more activity in the electroencephalographic delta and theta frequency range than do control subjects. Using magnetic source imaging (MSI) our study aimed to explore this phenomenon in the magnetoencephalogram (MEG), the distribution of its sources, and associations between symptom profiles and sources of low-frequency activity in the brain.Methods: Whole-head MEG recordings were obtained from 28 schizophrenic
Psychological Science, 2006
Biological Psychiatry, 2002
Patients suffering from Alzheimer&amp... more Patients suffering from Alzheimer's disease exhibit more activity in the conventional electroencephalographic delta and theta bands. This activity concurs with atrophy and reduced metabolic and perfusion rates, particularly in temporoparietal structures. Whole-head magnetoencephalographic recordings were obtained from 15 patients diagnosed with Alzheimer's disease and 19 healthy control subjects during a resting condition. The generators of focal magnetic slow waves were located employing a single moving dipole model. Dipole density in the delta and theta bands was enhanced in the Alzheimer's disease group compared with healthy control subjects. Slow-wave activity differed significantly between groups in temporoparietal regions of both hemispheres. Right temporoparietal slow-wave activity covaried with cognitive performance, whereas left temporal delta activity varied with a functional status scale. Our results support the predominant role of the temporoparietal areas in the diagnosis of Alzheimer's disease. Magnetoencephalography and the source analysis of focal slow activity in particular provide interesting and potentially clinically useful tools to assess functional modifications of patients' brain and to evaluate its relationship with the cognitive status.
Objective: The present study aimed at examining,the time course and topography of oscillatory bra... more Objective: The present study aimed at examining,the time course and topography of oscillatory brain activity and event-related potentials (ERPs) in response to laterally presented affective pictures. Methods: Electroencephalography was recorded from 129 electrodes in 10 healthy university students during presentation of pictures from the international affective picture system. Frequency measures and ERPs were obtained for pleasant, neutral, and unpleasant
Electroencephalography and clinical neurophysiology, 1997
The usefulness of MEG-based techniques in lateralizing and localizing the epileptogenic area was ... more The usefulness of MEG-based techniques in lateralizing and localizing the epileptogenic area was investigated in the present study. Spontaneous and methohexital-induced spikes were studied in a group of 15 patients with temporomesial epilepsy using a 37-channel neuromagnetometer. The accuracy of the magnetic source imaging was compared to the results of electrocorticographic (ECoG) recordings. Differences of drug-induced spike densities in the MEG recordings between both sides confirmed a similar lateralizing power of the MEG and ECoG recordings. Source location analyses based on a moving dipole model resp. a rotating dipole model were performed using a spherical head model. After subdivision of the volume of each patient's head, 8 cm3 cubicles containing at least 3 source locations were projected onto the individual MRI scan and resulted in source locations within or close to the presurgically defined primary epileptogenic area only in 3 of the 15 patients. Spike induction by m...
BMC psychiatry, 2006
The aim of this study was to investigate brain responses triggered by different wordclasses in dy... more The aim of this study was to investigate brain responses triggered by different wordclasses in dyslexic and control children. The majority of dyslexic children have difficulties to phonologically assemble a word from sublexical parts following grapheme-to-phoneme correspondences. Therefore, we hypothesised that dyslexic children should mainly differ from controls processing low frequent words that are unfamiliar to the reader. We presented different wordclasses (high and low frequent words, pseudowords) in a rapid serial visual word (RSVP) design and performed wavelet analysis on the evoked activity. Dyslexic children had lower evoked power amplitudes and a higher spectral frequency for low frequent words compared to control children. No group differences were found for high frequent words and pseudowords. Control children had higher evoked power amplitudes and a lower spectral frequency for low frequent words compared to high frequent words and pseudowords. This pattern was not pre...
Clinical neurophysiology : official journal of the International Federation of Clinical Neurophysiology, 2003
Focal slow waves in the delta and theta frequency range frequently appear in psychopathological c... more Focal slow waves in the delta and theta frequency range frequently appear in psychopathological conditions. Due to their focal nature they can be localized by dipole modeling. We previously reported regional clustering of slow waves in temporal and parietal cortex of schizophrenic patients whereas such activity is largely absent in normals. Here we examine, to what extent distribution of slow wave generators differentiates schizophrenic from depressive syndromes. The regional densities of generators of focal slow waves were determined during resting conditions in patients with DSM-IV diagnoses of schizophrenia (N=25) and depression (N=27) and in 18 healthy controls. Schizophrenic patients demonstrated accentuated temporal and parietal delta and theta dipole clustering, when compared to both the control and the depressive sample. In contrast, depressive patients had reduced frontal and prefrontal delta and theta dipole density relative to both schizophrenics and controls. This patter...
NeuroImage. Clinical, 2014
Deficits in social cognition including facial affect recognition and their detrimental effects on... more Deficits in social cognition including facial affect recognition and their detrimental effects on functional outcome are well established in schizophrenia. Structured training can have substantial effects on social cognitive measures including facial affect recognition. Elucidating training effects on cortical mechanisms involved in facial affect recognition may identify causes of dysfunctional facial affect recognition in schizophrenia and foster remediation strategies. In the present study, 57 schizophrenia patients were randomly assigned to (a) computer-based facial affect training that focused on affect discrimination and working memory in 20 daily 1-hour sessions, (b) similarly intense, targeted cognitive training on auditory-verbal discrimination and working memory, or (c) treatment as usual. Neuromagnetic activity was measured before and after training during a dynamic facial affect recognition task (5 s videos showing human faces gradually changing from neutral to fear or to...
Schizophrenia Research, 2003
When slow waves in the EEG delta and theta frequency range appear in the waking state, they may i... more When slow waves in the EEG delta and theta frequency range appear in the waking state, they may indicate pathological conditions including psychopathology. The generators of focal slow waves can be mapped using magnetic source imaging. The resulting brain maps may possibly characterize dysfunctional brain areas.The present study examined the stability of the density and distribution of MEG slow waves
Cognitive Brain Research, 2001
Science, 1995
Magnetic source imaging revealed that the cortical representation of the digits of the left hand ... more Magnetic source imaging revealed that the cortical representation of the digits of the left hand of string players was larger than that in controls. The effect was smallest for the left thumb, and no such differences were observed for the representations of the right hand digits. The amount of cortical reorganization in the representation of the fingering digits was correlated
Psychological Science, 2006
Neuroscience Letters, 2006
International Journal of Psychophysiology, 2010
t.- .•..~ .....· .•...·. rr attributed to pathological or 'dysfunctional' neural tissue (... more t.- .•..~ .....· .•...·. rr attributed to pathological or 'dysfunctional' neural tissue (Niedermeyer and Lopes' da Silva, 1987; Lewine. and Orrison, 1995). Similar to the interpretation of~~Jow oscillatory rhythms,during sleep stages as deafferelltation of the cortex due to thalamic hyperpolarisation (Steriade, 1997), abnormal focal slow wave activity in the waking state miQ'ht indicate fUllctiollal deafferelltatioll in the sense of
BMC Psychiatry, 2005
BACKGROUND: The present study was dedicated to investigate the influence of Methylphenidate (MPH)... more BACKGROUND: The present study was dedicated to investigate the influence of Methylphenidate (MPH) on cortical processing of children who were diagnosed with different subtypes of Attention Deficit Hyperactivity Disorder (ADHD). As all of the previous studies investigating power differences in different frequency bands have been using EEG, mostly with a relatively small number of electrodes our aim was to obtain
Biological Psychiatry, 2001
Background: Schizophrenic patients exhibit more activity in the electroencephalographic delta and... more Background: Schizophrenic patients exhibit more activity in the electroencephalographic delta and theta frequency range than do control subjects. Using magnetic source imaging (MSI) our study aimed to explore this phenomenon in the magnetoencephalogram (MEG), the distribution of its sources, and associations between symptom profiles and sources of low-frequency activity in the brain.Methods: Whole-head MEG recordings were obtained from 28 schizophrenic
Psychological Science, 2006
Biological Psychiatry, 2002
Patients suffering from Alzheimer&amp... more Patients suffering from Alzheimer's disease exhibit more activity in the conventional electroencephalographic delta and theta bands. This activity concurs with atrophy and reduced metabolic and perfusion rates, particularly in temporoparietal structures. Whole-head magnetoencephalographic recordings were obtained from 15 patients diagnosed with Alzheimer's disease and 19 healthy control subjects during a resting condition. The generators of focal magnetic slow waves were located employing a single moving dipole model. Dipole density in the delta and theta bands was enhanced in the Alzheimer's disease group compared with healthy control subjects. Slow-wave activity differed significantly between groups in temporoparietal regions of both hemispheres. Right temporoparietal slow-wave activity covaried with cognitive performance, whereas left temporal delta activity varied with a functional status scale. Our results support the predominant role of the temporoparietal areas in the diagnosis of Alzheimer's disease. Magnetoencephalography and the source analysis of focal slow activity in particular provide interesting and potentially clinically useful tools to assess functional modifications of patients' brain and to evaluate its relationship with the cognitive status.
Objective: The present study aimed at examining,the time course and topography of oscillatory bra... more Objective: The present study aimed at examining,the time course and topography of oscillatory brain activity and event-related potentials (ERPs) in response to laterally presented affective pictures. Methods: Electroencephalography was recorded from 129 electrodes in 10 healthy university students during presentation of pictures from the international affective picture system. Frequency measures and ERPs were obtained for pleasant, neutral, and unpleasant
Electroencephalography and clinical neurophysiology, 1997
The usefulness of MEG-based techniques in lateralizing and localizing the epileptogenic area was ... more The usefulness of MEG-based techniques in lateralizing and localizing the epileptogenic area was investigated in the present study. Spontaneous and methohexital-induced spikes were studied in a group of 15 patients with temporomesial epilepsy using a 37-channel neuromagnetometer. The accuracy of the magnetic source imaging was compared to the results of electrocorticographic (ECoG) recordings. Differences of drug-induced spike densities in the MEG recordings between both sides confirmed a similar lateralizing power of the MEG and ECoG recordings. Source location analyses based on a moving dipole model resp. a rotating dipole model were performed using a spherical head model. After subdivision of the volume of each patient's head, 8 cm3 cubicles containing at least 3 source locations were projected onto the individual MRI scan and resulted in source locations within or close to the presurgically defined primary epileptogenic area only in 3 of the 15 patients. Spike induction by m...
BMC psychiatry, 2006
The aim of this study was to investigate brain responses triggered by different wordclasses in dy... more The aim of this study was to investigate brain responses triggered by different wordclasses in dyslexic and control children. The majority of dyslexic children have difficulties to phonologically assemble a word from sublexical parts following grapheme-to-phoneme correspondences. Therefore, we hypothesised that dyslexic children should mainly differ from controls processing low frequent words that are unfamiliar to the reader. We presented different wordclasses (high and low frequent words, pseudowords) in a rapid serial visual word (RSVP) design and performed wavelet analysis on the evoked activity. Dyslexic children had lower evoked power amplitudes and a higher spectral frequency for low frequent words compared to control children. No group differences were found for high frequent words and pseudowords. Control children had higher evoked power amplitudes and a lower spectral frequency for low frequent words compared to high frequent words and pseudowords. This pattern was not pre...
Clinical neurophysiology : official journal of the International Federation of Clinical Neurophysiology, 2003
Focal slow waves in the delta and theta frequency range frequently appear in psychopathological c... more Focal slow waves in the delta and theta frequency range frequently appear in psychopathological conditions. Due to their focal nature they can be localized by dipole modeling. We previously reported regional clustering of slow waves in temporal and parietal cortex of schizophrenic patients whereas such activity is largely absent in normals. Here we examine, to what extent distribution of slow wave generators differentiates schizophrenic from depressive syndromes. The regional densities of generators of focal slow waves were determined during resting conditions in patients with DSM-IV diagnoses of schizophrenia (N=25) and depression (N=27) and in 18 healthy controls. Schizophrenic patients demonstrated accentuated temporal and parietal delta and theta dipole clustering, when compared to both the control and the depressive sample. In contrast, depressive patients had reduced frontal and prefrontal delta and theta dipole density relative to both schizophrenics and controls. This patter...
NeuroImage. Clinical, 2014
Deficits in social cognition including facial affect recognition and their detrimental effects on... more Deficits in social cognition including facial affect recognition and their detrimental effects on functional outcome are well established in schizophrenia. Structured training can have substantial effects on social cognitive measures including facial affect recognition. Elucidating training effects on cortical mechanisms involved in facial affect recognition may identify causes of dysfunctional facial affect recognition in schizophrenia and foster remediation strategies. In the present study, 57 schizophrenia patients were randomly assigned to (a) computer-based facial affect training that focused on affect discrimination and working memory in 20 daily 1-hour sessions, (b) similarly intense, targeted cognitive training on auditory-verbal discrimination and working memory, or (c) treatment as usual. Neuromagnetic activity was measured before and after training during a dynamic facial affect recognition task (5 s videos showing human faces gradually changing from neutral to fear or to...
Schizophrenia Research, 2003
When slow waves in the EEG delta and theta frequency range appear in the waking state, they may i... more When slow waves in the EEG delta and theta frequency range appear in the waking state, they may indicate pathological conditions including psychopathology. The generators of focal slow waves can be mapped using magnetic source imaging. The resulting brain maps may possibly characterize dysfunctional brain areas.The present study examined the stability of the density and distribution of MEG slow waves
Cognitive Brain Research, 2001
Science, 1995
Magnetic source imaging revealed that the cortical representation of the digits of the left hand ... more Magnetic source imaging revealed that the cortical representation of the digits of the left hand of string players was larger than that in controls. The effect was smallest for the left thumb, and no such differences were observed for the representations of the right hand digits. The amount of cortical reorganization in the representation of the fingering digits was correlated
Psychological Science, 2006
Neuroscience Letters, 2006