Latent inhibition depends on inhibitory attentional learning to the preexposed stimulus: Evidence from visual search and rule-learning tasks

Latent inhibition (LI) refers to findings of poorer learning with stimuli p reexposed as irrelevant, compared to novel stimuli. In order to investigate the role of attention in traditional LI, two experiments with human subjec ts were conducted. Experiment I used a simplified visual-search design. As in previous studies, but now with a simpler design, there was a LI-like eff ect, thereby supporting the position that attentional learning to irrelevan tly preexposed stimuli is reduced. Experiment 2 introduced conditions that were designed to exclude a potential contribution of novel popout to the vi sual-search LI-like effect. It was shown that the effect could be observed independently of contributions from novel popout. In addition, when partici pants were divided into good and poor attentional. learners on the basis of visual-search LI scores, traditional rule-learning LI was established in g ood attentional learners, whereas it was absent in poor attentional learner s. Together, these results indicate that visual-search procedures can be us ed to provide a measure for LI, and, as such, they support attention-based explanations of traditional LI. (C) 2001 Academic Press.