title: Selectivity of verbal memory deficit in schizophrenic patients and their relatives.
abstract: Some of the relatives of people with schizophrenia show impairments of memory and executive function. It is not known, however, whether within these domains there is a class of processes that is especially impaired. Seventy schizophrenic or schizoaffective patients, 115 of their relatives and 66 normal controls underwent a series of assessments evaluating modality specific recall/learning, and aspects of executive functioning, including, planning ability, spatial working memory, strategy formation and rapid mental flexibility. The pattern of performance across cognitive processes was assessed using z-scores that allow direct comparison between tests with different raw score metrics. Selectivity of deficit was evaluated by subtracting the z-score of each cognitive process from the mean of the z-scores of those remaining. Patients performed out worse than controls on most measures, with verbal immediate recall and visual memory/learning the most impaired. Their relatives showed lower scores than controls on verbal and visual memory/learning and strategy formation; verbal memory and strategy formation remained impaired after eliminating those relatives with a psychiatric diagnosis. Consistent with the findings in their schizophrenic kin, healthy relatives also showed disproportionate impairments in verbal immediate recall. Our finding of a selective deficit in verbal memory among relatives suggests that such impairment constitutes a familial, probably genetic, risk factor for schizophrenia.
authors.affiliation: Division of Psychological Medicine, Institute of Psychiatry, De Crespigny Park, London, United Kingdom. t.toulopoulou@iop.kcl.ac.uk
authors.forename: Timothea
authors.initials: T
authors.lastname: Toulopoulou
authors.forename: Robin G
authors.initials: RG
authors.lastname: Morris
authors.forename: Sophia
authors.initials: S
authors.lastname: Rabe-Hesketh
authors.forename: Robin M
authors.initials: RM
authors.lastname: Murray
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005192:Family Health; D005260:Female; D006801:Humans; D007859:Learning Disabilities / Q000503:physiopathology*; D008297:Male; D008568:Memory / Q000502:physiology; D008569:Memory Disorders / Q000503:physiopathology*; D008875:Middle Aged; D009483:Neuropsychological Tests; D012559:Schizophrenia / Q000235:genetics / Q000503:physiopathology*; D012565:Schizophrenic Psychology; D013223:Statistics as Topic; D014706:Verbal Learning / Q000502:physiology