Are spatial responses to visuospatial stimuli and spoken responses to auditory letters ideomotor-compatible tasks? Examination of set-size effects on dual-task interference.
Previous studies have paired a visual-manual Task 1 with an auditory-vocal Task 2 to evaluate whether the psychological refractory period (PRP) effect is eliminated with two ideomotor-compatible tasks (for which stimuli resemble the response feedback). The present study varied the number of stimulus-response alternatives for Task 1 in three experiments to determine whether set-size and PRP effects were absent, as would be expected if the tasks bypass limited-capacity response-selection processes. In Experiments 1 and 2, the visual-manual task was used as Task 1, with lever-movement and keypress responses, respectively. In Experiment 3, the auditory-vocal task was used as Task 1 and the visual-manual task as Task 2. A significant lengthening of reaction time for 4 vs. 2 alternatives was found for the visual-manual Task 1 and the Task 2 PRP effect in Experiments 1 and 2, suggesting that the visual-manual task is not ideomotor compatible. Neither effect of set size was significant for the auditory-vocal Task 1 in Experiment 3, but there was still a Task 2 PRP effect. Our results imply that neither version of the visual-manual task is ideomotor compatible; other considerations suggest that the auditory-vocal task may also still require response selection.
Department of Psychological Sciences, Purdue University, 703, Third Street, W. Lafayette, IN 47907-2081, USA. ykshin@psych.purdue.edu
Yun-Kyoung
YK
Shin
Robert W
RW
Proctor
D001288:Attention; D006801:Humans; D009949:Orientation; D010364:Pattern Recognition, Visual; D011597:Psychomotor Performance; D011930:Reaction Time; D012033:Refractory Period, Psychological; D013067:Speech Perception; D014705:Verbal Behavior