title: Similar verbal memory impairments in schizophrenia and healthy aging. Implications for understanding of neural mechanisms.
abstract: Memory is impaired in schizophrenia patients but it is not clear whether this is specific to the illness and whether different types of memory (verbal and nonverbal) or memories in different cognitive domains (executive, object recognition) are similarly affected. To study relationships between memory impairments and schizophrenia we compared memory functions in 77 schizophrenia patients, 58 elderly healthy individuals and 41 young healthy individuals. Tests included verbal associative and logical memory and memory in executive and object recognition domains. We compared relationships of memory functions to each other and to other cognitive functions including psychomotor speed and verbal and spatial working memory. Compared to the young healthy group, schizophrenia patients and elderly healthy individuals showed similar severe impairment in logical memory and in the ability to learn new associations (NAL), and similar but less severe impairment in spatial working memory and executive and object memory. Verbal working memory was significantly more impaired in schizophrenia patients than in the healthy elderly. Verbal episodic memory impairment in schizophrenia may share common mechanisms with similar impairment in healthy aging. Impairment in verbal working memory in contrast may reflect mechanisms specific to schizophrenia. Study of verbal explicit memory impairment tapped by the NAL index may advance understanding of abnormal hippocampus dependent mechanisms common to schizophrenia and aging.
authors: Brain Behavior Laboratory, Sha׳ar Menashe Mental Health Center, Mobile Post Hefer 37806, Israel; Rappaport Faculty of Medicine, Technion Institute of Technology, Haifa, Israel. Electronic address: mdsilver@tx.technion.ac.il.
authors: Henry
authors: H
authors: Silver
authors: Department of Biostatistics and Epidemiology, University of Pennsylvania, Philadelphia 19104-6021, USA. Electronic address: warren@upenn.edu.
authors: Warren B
authors: WB
authors: Bilker
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000523:psychology*; D016022:Case-Control Studies; D003071:Cognition / Q000502:physiology; D003072:Cognition Disorders / Q000150:complications / Q000523:psychology; D005260:Female; D015577:Geriatric Assessment / Q000379:methods / Q000706:statistics & numerical data; D006801:Humans; D008128:Logic; D008297:Male; D008569:Memory Disorders / Q000150:complications*; D061212:Memory, Episodic; D008570:Memory, Short-Term / Q000502:physiology; D008875:Middle Aged; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D011597:Psychomotor Performance; D012559:Schizophrenia / Q000150:complications* / Q000175:diagnosis; D012565:Schizophrenic Psychology; D014796:Visual Perception
keywords: Cognitive impairment; Dementia; Hippocampus; Prefrontal cortex; Psychosis