Flat affect is a major component of schizophrenia and is often also seen in neurological disorders. A preliminary set of comparisons were conducted to delineate neuropsychological mechanisms underlying flat affect in schizophrenia, and new measures are described for the assessment of affective deficits in clinical populations. Subjects were schizophrenic with flat affect (SZs), right brain-damaged (RBD), Parkinson's Disease (PDs), and normal control (NC) right-handed adults. Subjects were administered affective measures of expression and perception in both facial and vocal channels. For both perceptual and expressive tasks the SZs performed significantly less accurately than the NCs and the PDs but did not differ from the RBDs. This was the case for both face and voice. This finding lends support to the speculation that right hemisphere mechanisms, especially cortical ones, may be compromised among schizophrenics with flat affect.