Priming effects in schizophrenia: associative interference and facilitation as a function of visual context

Irrelevant stimuli that flank a fixated target may cause either facilitation or interference with target classification. Twenty schizophrenic patients, 20 depressed control patients, and 20 normal control subjects were compared on a flanker priming task that involved the linear display of a target surrounded by two flanking letters or digits. Choice reaction time between letter and digit targets was examined as a function of flanker condition and onset asynchrony between flankers and target. Facilitative priming occurred only with prior exposure of flankers compatible with the response required and was greater in degree with schizophrenic and depressed than with normal subjects. Interference from flankers incompatible with the response required less among schizophrenics than among other groups. Several different processes may be involved in the inhibition of irrelevant information by schizophrenics.