Cueing effects of target location probability and repetition.

The search performance for targets is improved when the targets appear in a specific location more frequently than in other locations. Although this phenomenon, called the "probability cueing effect," has been reported in past studies, it is unclear whether probability cueing is driven by statistical learning and/or intertrial facilitation of the target location. We investigated the underlying mechanisms for probability cueing effects by manipulating probabilities and repetitions of the target appearance at each target location. The first experiment demonstrated that the reaction time benefits of both statistical learning and intertrial facilitation contributed to the probability cueing effect. In contrast, the second and third experiments demonstrated that the probability cueing effect did not occur when target location repetitions on consecutive trials were fully or partially restricted. Also, any intertrial facilitation effects disappeared if there were more than one intervening trials. These results suggest that consecutive target location repetitions throughout the experiment facilitate learning of the target location probability.