Time and frequency domain event-related electrical activity associated with response control in schizophrenia

• Published in: Clinical neurophysiology 2010-10, Vol.121 (10), p.1760-1771
• Main Authors: Doege, Kathrin, Kumar, Mahendra, Bates, Alan Thomas, Das, Debasis, Boks, Marco Paul Maria, Liddle, Peter Francis
• Format: Article
• Language: English
• Subjects: Adult; Adult and adolescent clinical studies; Analysis of Variance; Biological and medical sciences; Brain; Brain - physiopathology; Brain Mapping; Cerebral Cortex - physiopathology; Electrodiagnosis. Electric activity recording; Electroencephalography - methods; Evoked delta and theta; Evoked Potentials - physiology; Functional Laterality - physiology; Go/no-go task; Humans; Investigative techniques, diagnostic techniques (general aspects); Male; Medical sciences; N200; Nervous system; Neurology; Neuropsychological Tests; P300; Psychology. Psychoanalysis. Psychiatry; Psychopathology. Psychiatry; Psychoses; Reaction Time - physiology; Schizophrenia; Schizophrenia - pathology; Schizophrenia - physiopathology; Schizophrenic Psychology; sLORETA; Statistics as Topic; Statistics, Nonparametric; Time Factors; Young Adult
• ISSN: 1388-2457; 1872-8952
• DOI: 10.1016/j.clinph.2010.03.049

Abstract Objective To confirm previously reported abnormalities in time domain EEG components during a go/no-go task in schizophrenia, and to test the hypothesis that patients exhibit abnormalities in frequency domain components reflecting indices of behavioural impairment. Methods EEG data were recorded from 17 male schizophrenia patients in a stable phase of illness and 17 healthy controls. Results As compared with controls, patients displayed smaller N200 amplitudes and less evoked theta for correct hit trials; and smaller N200 and P300 amplitudes and less evoked delta and theta for correct reject trials. Effect sizes were largest for evoked delta. Source localisation revealed reduced activation in schizophrenia patients during the N200 and P300 time windows in anterior and posterior cingulate, medial frontal gyrus and precuneus. Evoked delta and theta oscillations were significantly correlated with the variability of reaction times and the performance level statistic d -prime. Conclusions The results demonstrate impairment of frontal and parietal brain areas involved in response control in schizophrenia. They also suggest that the timing of oscillations in patients is less precise leading to smaller evoked amplitudes and more variable reaction times. Significance These findings add to the evidence that abnormal EEG oscillations contribute to impaired behavioural control in schizophrenia.