Neuropsychological function in schizophrenia. Selective impairment in memory and learning.

Unmedicated schizophrenic patients (according to DSM-III-R criteria) (n = 36) and age-matched normal controls (n = 36), balanced for parental socioeconomic status, were administered a battery of standardized neuropsychological tests. Patients showed generalized impairment relative to controls and a selective deficit in memory and learning compared with other functions. Selective impairment was not found on tests related to frontal system function (abstraction, verbal fluency, and motor). The observed pattern is consistent with greater involvement of the temporal-hippocampal system, against the background of diffuse dysfunction. Although impairment in memory and learning has been reported, the selectivity and relative severity compared with other behavioral functions have not been recognized. The specificity of this profile merits further examination. These findings lend support to the hypothesized importance of the temporal-hippocampal region in understanding the pathophysiology of schizophrenia.

Neuropsychological deficits in neuroleptic naive patients with first-episode schizophrenia.

BACKGROUND: Medication and chronicity have complicated past attempts to characterize the neuropsychological performance of patients with schizophrenia. There have been inconsistencies regarding the pattern, selectivity, and sources of observed deficits. Our objective was to comprehensively examine neuropsychological function in patients with schizophrenia who had never been exposed to neuroleptic medication, and who were experiencing their first episode (FE) of psychosis. METHODS: Subjects were consecutive recruitments that included 37 patients with FE schizophrenia who were never exposed to neuroleptics. These subjects were compared with 65 unmedicated, previously treated (PT) patients and 131 healthy controls. RESULTS: The patients groups had nearly identical profiles showing generalized impairment, particularly in verbal memory and learning, attention-vigilance, and speeded visual-motor processing and attention. Verbal memory and learning accounted for most of the variance between patients and controls and removing this effect substantially attenuated all other differences. By contrast, both the FE group and PT group continued to show highly significant deficits in verbal memory and learning after controlling for attention, abstraction, and all other functions. Some functions not typically implicated in schizophrenia (spatial cognition, fine motor speed, and visual memory) were more impaired in the PT group than in the FE group. CONCLUSIONS: Verbal memory, as a primary neuropsychological deficit present early in the course of schizophrenia, implicates the left temporal-hippocampal system. Neuropsychological evaluations before treatment permit differentiation of primary deficits from changes secondary to medication or chronicity. This is essential for developing a neurobehavioral perspective on schizophrenia.

Acute naming deficits following dominant temporal lobectomy: prediction by age at 1st risk for seizures.

Age at 1st risk for seizures may predict anomia following dominant anterior temporal lobectomy. We assessed confrontation naming before and 2 to 3 weeks after surgery in 45 right-handed patients grouped by side of focus and presence or absence of early (less than or equal to 5 years) risk factors. After left lobectomy, 6 of 10 (60%) patients with no early risks demonstrated significant decline (greater than or equal to 25%) in naming, but none of the patients with early risks showed this decline. After right lobectomy, there was no change. Cerebral representation of naming may be atypical in patients with early risks.

Acute effect of anterior temporal lobectomy on musical processing.

Patients with intractable epilepsy treated by anterior temporal lobectomy (Right, RT, n = 12; Left, LT, n = 9) and healthy controls (n = 12) with no musical training were prospectively evaluated with a standardized battery, including the Musical Aptitude Profile and the Seashore Tonal Memory Test. Before surgery, patients performed below controls (P less than 0.001), but there were no differences between RT and LT patients. After resection (2 weeks), RT patients showed a differential decline on tasks measuring perception of meter (P = 0.005) and tempo (P = 0.008) but not tonal processes. LT, and controls studied at the same time interval, showed no decline. The results support the role of the right hemisphere in specific aspects of musical processing.

Comparison of two short forms of the Wisconsin Card Sorting Test.

Two short forms of the Wisconsin Card Sorting Test (WCST) were evaluated. The WCST-64 consists of one deck of 64 cards; derived measures are number of categories obtained and number of perseverative responses. The WCST-3 includes measures of the number of cards required to complete three categories and the number of perseverative responses. WCST protocols from 37 schizophrenics, 20 temporal lobe epileptics, 11 patients with probable SDAT, and 54 normal controls, were scored using the three methods. Pearson correlations between WCST and WCST-64 scores ranged from.70 to.91. while correlations between WCST and WCST-3 were somewhat lower (.36 to.82). The WCST-64 was superior to the WCST-3 in agreement with the full WCST. The WCST-3 tended to underestimate the number of perseverative responses on the full WCST. Although the use of a short form reduces reliability, the WCST-64 appears to be an acceptable alternative when administration of the full WCST is not possible.