抄録
If the probability that a target item in a visual task is presented at a given location or with a given feature is high, the reaction times for biased targets are shorter than those for low probability targets. However, the relationship between manipulation of probabilistic information and this probability effect is unclear. In this study, we investigated the effects of the spatial and nonspatial probabilities associated with the onset of targets on attentional deployment. When targets appeared at high probability locations, reaction times for target discrimination were faster than those that appeared at less likely locations (Experiment 1). However, such a probability advantage did not appear when the targets' appearances were associated with the shapes of the placeholders, regardless of their locations (Experiment 2a). The probability effect reoccurred when participants were informed of the nonspatial probabilistic manipulation (Experiment 2b). These results suggest that the spatial probability is effective as an attentional cue without awareness, whereas the nonspatial probability is not.
