Temporal dissociation between distractors and targets: the impact of residual distractor processing on target responses.

The authors manipulated the extent of distractor interference with learned, mapped responses by presenting distractors to participants (N = 16) before, simultaneously with, or after the target. Interference was significantly less when the distractor preceded the target's presentation by 200 ms than when distractor and target were presented simultaneously. Interference decreased progressively with increasing intervals. For both simultaneous and temporally separated distractor-target presentations, incongruent distractors were associated with the greatest interference, and neutral and congruent distractors interfered to a lesser degree. Distractors at fixation had a crucially greater impact on goal-directed responses to the target than did distractors at periphery. The authors discuss the findings in the context of (a) the time course of the processing of all inputs, (b) the subsequent enhancement of target-related information and responses, and (c) the inhibition of distractor-related information and responses.