Psychosis subgroups differ in intrinsic neural activity but not task-specific processing

Psychosis probands as a whole showed poor antisaccade performance. As expected, Biotype-1 showed diminished intrinsic neural activity and the worst behavior, and Biotype-2 showed accentuated intrinsic activity and less deviant behavior. Both of these groups also exhibited less dynamic oscillatory phase synchrony. Biotype-3 showed no neurophysiological differences from healthy individuals, despite a history of psychosis. Interestingly, all psychosis subgroups showed normal (i.e., not different from healthy) preparatory modulation of visuocortical investment as a function of cognitive demands, despite varying levels of task performance. Similar analyses conducted subgrouping cases by psychotic symptomatology revealed fewer and less consistent differences, including no intrinsic activity differences between any clinical subgroup and healthy individuals. This study illustrates that (i) differences in intrinsic neural activity may be a fundamental characteristic of psychosis and need to be evaluated separately from stimulus-specific responses, and (ii) grouping patients based on multidimensional classification using neurobiological data may have advantages for resolving heterogeneity and clarifying illness mechanisms relative to traditional psychiatric diagnoses.