Memory and IQ in schizophrenia and temporal lobe epilepsy

Memory and IQ in schizophrenia and temporal lobe epilepsy

174 gender was seen for Cognitive Flexibility, Fine Motor, and Gross Motor, reflecting superior performance in male subjects. Independent of gender, ...

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gender was seen for Cognitive Flexibility, Fine Motor, and Gross Motor, reflecting superior performance in male subjects. Independent of gender, there was a trend linking soft signs with decreased cognitive flexibility, gross motor ability, and attention. Contrary to our expectations, there were no interactions on neuropsychological performance as a function of soft signs and gender. These results suggest a role for neurologic compromise in schizophrenic patients of both genders, although male schizophrenics clearly emerged as having more severe soft signs. This is consistent with reports of a higher prevalence of brain morphological anomalies in male than female.

GOAL-DIRECTED VISUOMOTOR BEHAVIOUR - DYSFUNCTIONAL INTERACTION OF EYE- AND HANDMOVEMENTS IN SCHIZOPHRENIA W. Gaebel*, W. Wiilwer Department of Psychiatry, Heinrich-Heine-University, Berg&he Landstrab 2, D-4000 Dus-seldotf 12, Germany A recent neuropsychological model of schizophrenia emphasizes a failure to integrate stored memories of past regularities of perceptual input with ongoing motor programs in the control of current perception, possibly arising from a dysfunction of limbic input to the basal ganglia (Gray et al. 1991). Behavioural predictions based on this model were tested in goal-directed visuomotor tasks (e.g. Trailmaking B). - Performance strategy was analyzed by means of eye- and hand-movements in 23 acute schizophrenics, 17 acute depressives (DSM-III-R), and 21 normal controls. Tasks were displayed on a video-monitor, on which a cursor could be moved by a track-ball. Eye movements were recorded by infrared comeal-reflection pupil centre measurement. All subjects were assessed twice within four weeks, a subsample of patients again at discharge. Sequences of planning, acting, and pausing, operationalized by means of spatial and temporal characteristics of eye and hand-movements, were converted into transition probabilities and were subjected to factor analysis. According to a derived “strategy factor”, schizophrenics’ performance strategy was significantly different from normals’. Deviant strategies were related to poorer overall performance, but neither to psychopathology nor to drug dosage, and remained stable over time. According to the model, a trait-like subclinical disruption in the smooth running of motor programs for goal-directed behavior was confumed in schizophrenia.

MEMORY AND PLASMA HVA CHANGES SCHIZOPHRENIA: ARE THEY EPISODE MARKERS? M.W. Gilbertson.

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D.P. van Kamrnen*

Highland Drive VA Medical Center, Pittsburgh, PA 15206, USA

Memory impairments are among the most consistently reported findings in studies of schizophrenic cognition. Unfortunately little is reliably known about the impact of medication and course of illness on such findings. We propose that dynamic changes in mnemonic function within patients while unmedicated over time may provide clues to understanding the underlying neural substrate of schizophrenia. Using a within subject methodology, we examined changes in standardized memory function and catecholamine function as 29 patients were withdrawn from neuroleptic medication. Our data show that in patients who relapsed within 6 weeks of medication withdrawal, selective verbal associative memory deficits emerged which precede clinical changes. These changes cannot be explained by attentional difficulties or level of observable psychosis. Such changes do not occur in patients who remain clinically stable 6 weeks following neuroleptic withdrawal. Our data also suggest that memory changes show a significant inverse relationship to changes in plasma HVA levels but not plasma MHPG. We conclude that verbal memory deficit with associated increased plasma HVA may constitute a relapse prodrome and reflect early changes in the medial temporal-hippocampal complex. These findings argue for the importance of continued longitudinal, within-subject approaches to understanding the dynamic nature of neurocognitive deficit in schizophrenia.

MEMORY AND IQ IN SCHIZOPHRENIA TEMPORAL LOBE EPILEPSY

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J. Gold*, T. Blaxton, B. Hemann, C. Randolph, P. Fedio, T. Goldberg, W. Theodore, D. Weinberger NIMH Neuroscience Center at St Elizabeths, 2700 Martin Luther King Jr. Avenue, S.E., Washington, DC 20032, USA Recent neuroimaging and neuropsychological studies have suggested temporal lobe abnormalities in patients with schizophrenia. To investigate this anatomic hypothesis functionally, we compared the performance of 70 patients with schizophrenia (SC), and 72 patients with lateralized temporal lobe epilepsy (30 with a left temporal focus, 42 with a right temporal focus) using the Wechsler Memory Scale-Revised and the Wechsler Adult Intelligence Scale-Revised. The three patient groups did not differ in age, education, or Full Scale IQ. Patients with right TLE had significantly better verbal memory than either the left TLE or SC patients. The SC patients had worse visual memory than either TLE group which did not differ from each other. A repeated measures analysis of the General Memory Index and Delayed Memory Index revealed a significant group by time interaction term. This interaction revealed that in SC, the Delayed Index score was higher than General Index (83.6 vs 80.8). whereas they were lower in both TLE groups (RTLE: 90.9 vs 93; LTLE: 79 vs 83.6). The results suggest that memory impairment in schizophrenia differs qualitatively from that in either TLE group, and demonstrates the limits of a lateral&d temporal lobe model of schizophrenic cognitive impairment.