Object-name selection in psychiatric patients before and after neuroleptic therapy.

An object-name selection test was administered to 16 newly admitted schizo phrenic, non-schizophrenic psychotic and non-psychotic patients on admission when they were drug-free, and again 4-6 weeks later, following treatment with neuroleptics. Sixteen healthy, drug-free age-matched and sex-matched controls were similarly tested on two occasions 4-6 weeks apart. Schizophrenic and non-schizophrenic psychotic subjects made significantly more association-type errors than non-psychotic subjects and controls. A signifi cant reduction in association-type errors which was observed in both psychotic patient groups on the second testing occasion may be attributed to medication. The data suggest that overinclusive thinking, as measured by the object-name selection test, is a feature of both schizophrenic and non-schizophrenic psychosis. It is concluded that tests of overinclusion are therefore of limited diagnostic utility although they may be of value in monitoring response to treatment.

The perception of visual ambiguous figures in schizophrenia and Parkinson's disease.

The frequency of reversal and dominance of aspect of three versions of an ambiguous Schröder staircase were studied in patients with a diagnosis of either schizophrenia or Parkinson's Disease (PD), and in a mixed group of psychiatric patients before and after prolonged neuroleptic therapy. It was found that schizophrenics perceived the staircases from above for significantly less time, and had a (nonsignificant) tendency to have more reversals than controls. PD patients saw the staircases from above for significantly more time, and also had (nonsignificantly) more reversals than controls. In the psychiatric patients, long term neuroleptic therapy had no significant effect on either reversal rate or dominance of aspect. When the contrast and the luminance of the stimulus were manipulated, normal subjects reported significantly less reversals and significantly increased dominance of the superior aspect when the contrast of the stimulus was reduced. Changing the luminance had no significant effect. The implications of these results for visual abnormalities in schizophrenia and Parkinson's Disease are discussed.