DISRUPTED LATENT INHIBITION IN THE RAT WITH CHRONIC AMPHETAMINE OR HALOPERIDOL-INDUCED SUPER-SENSITIVITY - RELATIONSHIP TO SCHIZOPHRENIC ATTENTION DISORDER

Abstract

Latent inhibition (LI) is an attentional process by which animals learn to ignore a stimulus that is repeatedly presented without reinforcement. This ability to tune out a motivationally irrelevant stimulus is disrupted by pharmacological manipulations producing hyperdopaminergic states. In experiment (exp) 1, LI was disrupted following 5 daily administrations of 4 mg/kg d-amphetamine. In exp 2 the disruptive effects of d-amphetamine were eliminated by concomitant administration of chlorpromazine. Exp 3 showed that LI could also be disrupted with 1 mg/kg d-amphetamine coupled with dopamine receptor supersensitivity produced by prolonged pretreatment with haloperidol. Pharmacological disruption of LI may provide an animal analog of the defective stimulus filtering thought to characterize at least some forms of [human] schizophrenia.