[Differences in latent inhibition between men and women under conditions of nonverbal visually-spaatial masking]

In order to study gender differences in development of the latent inhibition (LI) and the influence of laterality (hemisphere) factor, two groups of subjects were examined. In the preexposure phase, subjects of the control group were presented with a pair of geometric figures, which appeared either in the right or in the left visual hemifield (at random) with the exposure time of 80 ms. A subject had to compare the figures in a pair and to press a button in case of their identity. In the preexposure (experimental) group, the subject solved the same task, but half of them was presented with the same set of stimuli which appeared in the right hemifield, another half of subjects received these stimuli in the left hemifield. Simultaneously with the target stimuli, the opposite hemifield was stimulated with a nonattended symbol "[symbol: see text]". In the test phase, all the subjects (both of the control and experimental groups) had to respond to the symbol "[symbol: see text]" (previously nonattended in the experimental group), which appeared in part of the trials, by pressing the button. Pairs of stimuli which had been target ones in the preexposure phase, became masking stimuli in the test phase. Correct responses were reinforced by presentation of a special sound. The number of trials required for acquisition of the instrumental contingency served as an index of the LI. Analysis of variance showed that significant strong effect of the LI was observed only in men (comparison between the control and preexposure groups), while there was no significant difference between women of the control and preexposure groups. There was no laterality effect. Gender differences and hemispheric asymmetry in the LI organization are discussed.