Do people with schizophrenia have differential impairment in episodic memory and/or working memory relative to other cognitive abilities?
Efforts to identify differential or core cognitive deficits in schizophrenia have been made for several decades, with limited success. Part of the difficulty in establishing a cognitive profile in schizophrenia is the considerable inter-patient heterogeneity in the level of cognitive impairment. Thus, it may be useful to examine the presence of relative cognitive weaknesses on an intra-person level. In the present study we examined the rates of significant intra-person differences between crystallized verbal ability versus five other cognitive abilities among 127 persons with schizophrenia or schizoaffective disorder and 127 demographically matched normal comparison (NC) subjects. We found that the rates of significant discrepancies above the NC group base-rates was significantly greater in reference to those discrepancies involving visual memory relative to those associated with auditory memory, working memory, processing speed, and perceptual organization. The findings conflict with prior suggestions that working memory or auditory episodic memory are differential or core deficits in schizophrenia, and highlight the importance of considering visual memory in characterizing the cognitive effects of this condition.
Palmer
Barton W
BW
Department of Psychiatry, University of California, San Diego, La Jolla, CA, USA. bpalmer@ucsd.edu
Savla
Gauri N
GN
Fellows
Ian E
IE
Twamley
Elizabeth W
EW
Jeste
Dilip V
DV
Lacro
Jonathan P
JP
D000328:Adult; D001288:Attention; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D008569:Memory Disorders / Q000209:etiology*; D008570:Memory, Short-Term / Q000502:physiology*; D008875:Middle Aged; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales; D011597:Psychomotor Performance; D012559:Schizophrenia / Q000150:complications*; D012720:Severity of Illness Index; D014705:Verbal Behavior / Q000502:physiology; D014796:Visual Perception / Q000502:physiology