1. Subjects with schizoaffective disorder have an impairment in early visual information processing known as backward masking. 2. Backward masking studies in schizoaffective disorder have not established if the deficit: is state- or trait-related; is associated with negative symptoms or neuroleptic treatment; or is partially attributable to lithium treatment. 3. Integration and interruption are mechanisms of backward masking in schizoaffective disorder, but experiments maximizing interruption only, have not been performed. 4. Studies isolating the transient visual channels have not been performed in patients with schizoaffective disorder.