[Dysfunctions of space perception and spatial ability in schizophrenia (author's transl)]

Thirty-seven acute schizophrenics and 25 normal subjects were investigated with regard to their spatial perception, representation, and their spatial ability, Schizophrenics showed significantly poorer performances (in terms of quantity) in those variables, which characterized the ocular apprehension of structures and wholes, the relation of parts to a whole, or the analysis of a whole in its various components as well as the availability of visual engrams, partly in the sense of spatial representation, and the practical realization of imagined spatial configurations. On the other hand, in ocular apprehension, interpretation, and when necessary the practical realization of two-dimensional represented spatial symbols and configurations and perspective abilities there was only statistical trend for quantitatively poorer performances in schizophrenics compared with healthy persons. Factor analysis of the intercorrelation matrices for 14 variables separated out the same 4 factors in each group for space perception and spatial ability. In spite of the demonstrated "quantitative" differences for the single variables between the two groups a marked similarity in a "qualitative" sense was found, when the two-factor structures were compared mathematically (similarity coefficient: 0.664). In order to specify these differences, 56 schizophrenics were classified as paranoid or nonparanoid and investigated in the above-mentioned manner. While these groups did not show any significant quantitative difference concerning their performances at variable level, they showed entirely different structures using factor analysis. Spatial perception of the paranoid schizophrenics seemed less structured and their perceptual conception less systematical. On the other hand, when factor structures from nonparanoids and healthy controls were compared mathematically, both groups showed a marked similarity (0.783). An attempt was made to relate these results to other findings of literature and to theories of cognitive and perceptual dysfunctions of schizophrenics.