Backward-masking performance in chronic and nonchronic schizophrenics, affectively disturbed patients, and normal control subjects.

There is ample evidence that schizophrenics exhibit a backward masking deficit. To what extent other psychotic patients are susceptible to visual masking is still an open question. Likewise, differences between subgroups of schizophrenics have to be further explored. In the present study a computerized backward masking task was applied to 30 schizophrenics, 18 affectives and 20 normals. Results confirmed previous findings of a performance deficit in the schizophrenics. However, affectively disturbed patients performed even poorer than the schizophrenics. The most outstanding finding when the group of schizophrenics was split into different subgroups was the significant differences that appeared between chronic and nonchronic patients. The latter group (n = 8) performed as well as the normals, while the chronic schizophrenics (n = 22) showed evidence of a performance deficit comparable to the affectives.