TY - JOUR
T1 - Impairment of recognition memory in schizophrenia
T2 - Event-related potential study using a continuous recognition task
AU - Kim, Myung Sun
AU - Jun, Soo Kwon
AU - Kang, Seung Suk
AU - Youn, Tak
AU - Kang, Kyung Whun
PY - 2004/10
Y1 - 2004/10
N2 - Recognition memory and the dissociation of immediate and delayed repetition in schizophrenic patients were investigated using event-related potential (ERP) and a continuous word recognition task. In total, 14 schizophrenic patients and 14 age and gender-matched control subjects, were recruited. Among 240 stimulus words used, 40 words were not repeated, 100 were repeated immediately, and 100 were repeated after five intervening words. Both schizophrenic and control groups responded faster to words repeated immediately than to words repeated after a delay and to new words. However, schizophrenic patients responded less accurately to words repeated immediately and to words repeated after a delay than the controls. In terms of ERP, schizophrenic patients showed significantly reduced N200, late positive component (LPC), and N400 amplitudes, and a more frontally-distributed N200 topography than the controls. For controls, immediate repetition was associated with a large LPC amplitude and the absence of N400, while delayed repetition was associated with a small LPC amplitude and the presence of N400. However, this dissociation between immediate and delayed repetition was not observed in schizophrenic patients. All of these results suggest that schizophrenic patients have recognition memory impairment, the cause of which may range from early encoding, and memory search to late retrieval.
AB - Recognition memory and the dissociation of immediate and delayed repetition in schizophrenic patients were investigated using event-related potential (ERP) and a continuous word recognition task. In total, 14 schizophrenic patients and 14 age and gender-matched control subjects, were recruited. Among 240 stimulus words used, 40 words were not repeated, 100 were repeated immediately, and 100 were repeated after five intervening words. Both schizophrenic and control groups responded faster to words repeated immediately than to words repeated after a delay and to new words. However, schizophrenic patients responded less accurately to words repeated immediately and to words repeated after a delay than the controls. In terms of ERP, schizophrenic patients showed significantly reduced N200, late positive component (LPC), and N400 amplitudes, and a more frontally-distributed N200 topography than the controls. For controls, immediate repetition was associated with a large LPC amplitude and the absence of N400, while delayed repetition was associated with a small LPC amplitude and the presence of N400. However, this dissociation between immediate and delayed repetition was not observed in schizophrenic patients. All of these results suggest that schizophrenic patients have recognition memory impairment, the cause of which may range from early encoding, and memory search to late retrieval.
KW - Event-related potential
KW - Late positive component
KW - N200
KW - N400
KW - Recognition memory
KW - Schizophrenia
UR - http://www.scopus.com/inward/record.url?scp=7944237789&partnerID=8YFLogxK
U2 - 10.1111/j.1440-1819.2004.01287.x
DO - 10.1111/j.1440-1819.2004.01287.x
M3 - Article
C2 - 15482576
AN - SCOPUS:7944237789
SN - 1323-1316
VL - 58
SP - 465
EP - 472
JO - Psychiatry and Clinical Neurosciences
JF - Psychiatry and Clinical Neurosciences
IS - 5
ER -