Clinical features of latent inhibition in schizophrenia

Paradigms of Latent Inhibition (LI) are inter-species and derived from lear ning theories. They are considered as tools which allow the attentional pro cesses to be studied. The absence of LI is interpreted as difficulty in dis criminating relevant and irrelevant stimuli. Abolition of LI has been shown in acute schizophrenics. The objectives of our study were partly to valida te an LI paradigm, based on a contingency detection between two stimuli, in healthy subjects, and partly to analyse LI in schizophrenics. The study in cluded 105 subjects (65 patients and 40 controls). Patients fulfilled the D SM IV diagnosis of schizophrenia. 35 in the acute phase and 30 in the chron ic phase. We observed a loss of LI for acute schizophrenics, and an enhance ment of LI for chronic schizophrenics. The variations in Ll are interpreted from the perspective of a disturbance in the attentional processes. The LI status in acute schizophrenics appears to correlate with the clinical crit eria with a prognostic value (low intensity of the negative dimension, late age at the first hospitalization). Moreover, the enhancement of LI correla tes with the negative dimension of schizophrenic disease. This correlation is found in acute and chronic schizophrenics. It suggests that the variatio ns of LI may be an indicator of adaptive strategies to a cognitive dysfunct ion specific to schizophrenia. (C) 2001 Elsevier Science B.V. All rights re served.