Autonomic responsivity to variable input rates among schizophrenics classified on the process-reactive dimension.

Schizophrenic groups rated low (reactive), intermediate, and high (process) on the Elgin Prognostic Scale and a group of normal Ss discriminated between matched and unmatched pairs of nonsense syllables under varying rates of input. Continuous PGR measures were recorded as the Ss responded to the syllable pairs. Stimulus overload (defined as the extent to which the Ss were unable to respond appropriately) was assessed and shown to be consistent across groups. The groups were differentiated as to PGR responsivity. Among the schizophrenic Ss, the reactive group was the most responsive and the process Ss were least responsive to increases in rate of input.