Four experiments examined whether the psychological refractory period (PRP) effect can be eliminated with ideomotor compatible (IM) but not stimulus-response compatible (SR) tasks, as reported by AG Greenwald and HG Shulman (1973). Their tasks were used: a left or right movement to a left-or right-pointing arrow (IM) or to the word left or right (SR) for Task 1; saying" A" or" B"(IM) or" 1" or" 2"(SR) to an auditory A or B for Task 2. The stimulus onset asynchronies were 0, 100, 200, 300, 500, and 1,000 ms in Experiment 1, and only 0, 100, 200, and 1,000 ms in Experiments 2-4. The arrow was in the center of the screen in Experiments 1-3 and to the left or right in Experiment 4. As in Greenwald and Shulman's Experiment 2, the instructions stated that most often the 2 stimuli would be presented simultaneously. A PRP effect was obtained in all conditions, most likely because response-selection decisions are required even for IM tasks.(PsycINFO Database Record (c) 2016 APA, all rights reserved)