中  華  心  理  學  刊
民92，45卷，3期，227-241

Yi-Hsing Hsieh（Deaprtment of Psychology, The Ohio State University）

Abstract

Past research suggested that an abruptonset distractor mayor may not override an endogenous cue, depending on spatial certainty of the endogenous cue. Yet the underlying competitive mechanisms are still not clear. In two experiments, the cue-to-distractor stimulus onset asynchronies (SOAs) and spatial distance between cued and distractor locations were manipulated. Following a central cue, an abrupt flash occurred in any location that was never centrally cued. Using EOG electrodes to monitor eye movements, the reaction times to identification of the target were measured. For more than 200 ms cue-to-distractor SOA, the nearest distractor produced the largest interruption (Experiment 1). In contrast, for 84 ms cue-to-distractor SOA, the farthest distractor produced the largest interruption (Experiment 2). In conclusion, the extent to which an abrupt-onset distractor will override a central cue depends on interaction of the cue-to-distractor SOA and spatial distance between the cued location and the distractor.

Keywords：exogenous/endogenous orienting, interaction ； interruption