||Visual attention and temporal discrimination: Differential effects of automatic and voluntary cueing?
Yeshurun and Levy 2003) reported that visual attention impairs temporal dis- crimination in a temporal gap detection task. To assess whether this counter- intuitive finding generalizes to another temporal discrimination task, we examined the influence of visual attention on temporal-order discrimination. Experiment 1 showed that an exogenous cue automatic orienting) impairs temporal-order dis- crimination. In contrast, however, Experiment 2 revealed that an endogenous cue voluntary orienting) facilitates temporal-order discrimination. Experiment 3 addressed whether these discrepant results are due to cue type or to cue predict- ability and revealed that a nonpredictive endogenous cue induces the same effect on temporal discrimination as the exogenous cue in Experiment 1. The complete pattern of results shows that automatically oriented attention impairs temporal- order discrimination, whereas voluntary oriented attention enhances it. Thus, the results emphasize the different nature of automatic and voluntary orienting. It is suggested that both kinds of attentional orienting operate at different processing levels within the visual system.