Response to an intervening event reverses nonspatial repetition effects in 2AFC tasks: Nonspatial IOR?

The repetition effect in two-alternatiave forced choice (2AFC) tasks is a cornerstone effect in human cognition. Yet the experiments described here show that the customary benefit of repetition reverses to a cost of repetition when participants respond to an irrelevant event between targets. In Experiments 1A–1C, participants made manual 2AFC decisions to both of two consecutive targets on a trial and, on some trials, also made a manual …