Neuropsychological impairment with schizophrenia vs. acute and chronic cerebral lesions.

Performed detailed neuropsychological evaluations with 25 recently hospitalized schizophrenics in whom systematic neurologic workups had failed to reveal CNS disease. Efforts were made to minimize possible effects of drug-induced extrapyramidal symptoms on test performance. Although the schizophrenics showed some neuropsychological impairment relative to 25 normals, their deficits were not as severe as those of patients known to have either acute or chronic brain disorders (N = 25). The diagnostic accuracy achieved by the tests supports their use in short-term treatment facilities when the differential diagnosis includes schizophrenia and brain disorder, especially acute brain disorder. Schizophrenics' neuropsychological impairment was more correlated with degree of EEG abnormality than with degree of psychosis, which suggests a possible organic basis for the deficits that they showed on testing.

Neuropsychological findings with pseudoxanthoma elasticum.

It has been reported that the disease pseudoxanthoma elasticum (PXE) is associated with a high incidence of neurologic and psychiatric symptoms, which are possibly due to cerebrovascular ischemia. These reports are based mainly upon clinical observations made without reference to control group data. We have compared the results of 27 PXE patients with results of a control group on a battery of objective neuropsychological and personality tests. The PXE group showed only very mild deficits on extensive neuropsychological testing, a finding which argues against any marked involvement of cerebral vessels in these patients. Similarly, the personality test results did not reveal significant psychiatric disturbances which could be attributed to PXE. Possible reasons for the descrepancy with previous reports include the subjective data and much older PXE patients on which those reports are based. The need for systematic neuropsychological research with older PXE patients and control groups is suggested.

Comparison of Wechsler Adult Intelligence Scale indices of cerebral disfunction.

This study assessed and compared the diagnostic accuracies of eight cerebral dysfunction indices based upon the Wechsler Adult Intelligence Scale (WAIS). Patients with extreme values of the Halstead Impairment Index were used to compose Impaired and Not Impaired groups. The Impaired group did significantly worse than the Not Impaired group on all 11 WAIS subtests, and there was little overlap between the groups in Full Scale IQ. The WAIS cerebral dysfunction indices ignore such differences in over-all level of performance and instead use the eight indices predicted impairement status at levels which exceed chance, but the total correct classification rates were quite modest. Statistical correction for group age differences reduced classification rates even more. Deviation score analyses were employed to assess relative strengths and deficits on the WAIS subtests, controlled for over-all level of performance. Compared to the Not-impaired group, Impaired subjects did relatively poorly on Block Design and Object Assemby, and relatively well on Information, Comprehension, Vocabular, and Picture Completion. Significant education effects and education by impairment status interactions also occurred for several subtests. It was concluded that the WAIS indices have limited value in screening for cerebral dysfunction, and reasons for this were discussed.

Electromyograph responses and performance success estimates as a function of internal-external control.

For 12 externally scoring college women, marginally significant correlations of EMG recordings with self-estimates of success in tensing forearm muscles (-.50) and with success in relaxing these muscles (-.54) were obtained. Similar correlations for 12 internally scoring women were much smaller. Analysis of variance of means had indicated no differences in ability of these groups to control muscles of the forearm.