Schizotypy and lateralised negative priming in schizophrenicsʹ and neuroticsʹ relatives

Schizophrenicsʹ relatives were compared with neuroticsʹ relatives on a range of schizotypy scales and a hemisphere information processing (negative priming) task. On most of the schizotypy scales schizophrenicsʹ relatives had lower scores than neuroticsʹ relatives, and also as compared with the normative data for the questionnaires used. This might have been due to volunteer bias or to defensive responding, though if the latter was the case it was not reflected in the level of ‘Lie’ scale scoring found among schizophrenicsʹ relatives. The experimental task showed no significant differences when subjects were compared according to relativesʹ status. However, two significant differences did emerge when the total sample was divided on the basis of high/low schizotypy scores: high schizotypes showed (a) a lack of visual field asymmetry in lateralised negative priming, and (b) unusually fast overall reaction times to stimuli in the left visual field. Both observations are consistent with some recent speculations about hemisphere functioning as it relates to information processing and activation bias in schizophrenia and schizotypy.