Working memory and schizophrenia: evidence for slowed encoding.
Previous studies have found impairments in working memory in individuals with schizophrenia, but have not identified the underlying information processing deficit. Because schizophrenia is associated with slowed cognitive processing, deficits on working memory tests may be due to decreased speed of encoding rather than an inability to maintain information over time. This hypothesis was examined using a Delayed Match to Sample (DMTS) Test. Task difficulty under 0-delay conditions was equated by individually establishing the stimulus presentation time needed to reach approximately 80% accuracy. Schizophrenia participants required longer presentation durations, but there were no group differences under delay conditions when performance was equated in the 0-delay condition. These results suggest that poor working memory performance in schizophrenia results from slowed encoding processes.
Hartman
Marilyn
M
Psychology Department, University of North Carolina, Davie Hall CB# 3270, Chapel Hill, NC 27599-3270, USA. hartman@email.unc.edu
Steketee
Mareah C
MC
Silva
Susan
S
Lanning
Kristi
K
McCann
Heather
H
D000293:Adolescent; D000328:Adult; D014150:Antipsychotic Agents / Q000627:therapeutic use; D005260:Female; D006760:Hospitalization; D006801:Humans; D007902:Length of Stay; D008297:Male; D008569:Memory Disorders / Q000175:diagnosis / Q000209:etiology*; D009483:Neuropsychological Tests; D010343:Patient Admission / Q000706:statistics & numerical data; D012559:Schizophrenia / Q000150:complications* / Q000188:drug therapy / Q000534:rehabilitation
D014150:Antipsychotic Agents