Attention related ERP components in schizophrenic patients-scalp current density analysis.
Grant-in-Aid for Scientific Research (C)
|Allocation Type||Single-year Grants|
|Research Institution||Teikyo University(1998)|
The University of Tokyo(1996-1997)
NAKAGOME Kazuyuki Teikyo University School of Medicine, Dept of Psychiatry, lecturer, 医学部, 講師 (30198056)
ITOH Kenji University of Tokyo, Graduate School of Medicine, Dept of Speech and Cognitive S, 医学部, 助手 (80010106)
FUKUDA Masato Gunma University School of Medicine, Dept of Neuropsychiatry, associate professo, 医学部, 助教授 (20221533)
HIRAMATSU Ken-Ichi University of Ryukyu, Faculty of Medicine, Dept of Psychiatry, associate profess, 医学部, 助教授 (50218814)
|Project Period (FY)
1996 – 1998
Completed(Fiscal Year 1998)
|Budget Amount *help
¥2,100,000 (Direct Cost : ¥2,100,000)
Fiscal Year 1998 : ¥300,000 (Direct Cost : ¥300,000)
Fiscal Year 1997 : ¥300,000 (Direct Cost : ¥300,000)
Fiscal Year 1996 : ¥1,500,000 (Direct Cost : ¥1,500,000)
|Keywords||MMN / N2b / multi-channel EEG / SCD / Schizophrenia / 多チャンネル脳波 / ScD / 注意機能 / N26 / SCD / 精神分裂病 / 事象関連電位 / scalp current density(SCD)|
Among various psychatric symptoms displayed in persons with schizophrenia, attentional deficits is one of those which are frequently observed and profoundly affect the severity of social skills dysfunction leading to the difficulty in maintaining their quality of life. However, not enough studies have been conducted to elucidate the pathophysiological basis of the symptom. Moreover, previous studies suggest that persons with schizophrenia show a deficiency in controlled attentional processing, whereas, a more recent view suggest that they also show a distortion in the preattentive processing. This study was aimed to clarify these problems using event-related potentials (ERP), one of the psychophysiological methods, which enabled us to discriminate the preattentive processing from controlled processing by measuring several negative components, such as MMiN, Nd, N2b, Ni. These components are considered to reflect different aspects of attention and/or vigilance level, which was investigat
ed in relation to other clinical indices. The interesting findings which have been obtained so far are listed below.
1) MMN and N2b amplitudes were significantly reduced in persons with schizophrenia as compared with the normals, the difference being more prominent for N2b.
2) Persons with schizophrenia clearly showed a sustained negativity following MMN in the unattended condition, which is reported to reflect the automatic preparation for detecting possible subsequent stimulus changes, whereas, it was displaced by an attenuated N2b in the normals. The amplitude of the sustained negativity showed a significant correlation with the counting accuracy of the deviant stimulus, suggesting that persons with schizophrenia, presumably due to the deficient controlled processing, owe much to automatic processing in the deviant stimulus detection.
3) N1 amplitude in either ear of stimulation, performance level of counting accuracy and N2b amplitude to the right ear of stimulation were related to social skills indices assessed in a structured role play test. The finding suggested that the vigilance level and controlled stimulus detection processing are relevant to the social skills in persons with schizophrenia.
4) SCD mappings obtained using a multi-channel (128ch) BEG system showed a source/sink pattern in bilateral temporal regions and a current sink in the right frontal and parietal regions regarding MMN in normal subjects, which is in line with the previous studies, suggesting that the right hemisphere may play a significant role in the preattentive stimulus detection. Less
Research Products (3results)