PUPILLARY AND ELECTROMYOGRAPHIC CHANGES DURING AN IMAGERY TASK

This study examined the relationship between muscle activity and the increased pupillary dilation observed during cognitive tasks when S is required to indicate task completion. Pupillary and EMG activity were monitored while Ss generated images to words. In two groups, Ss indicated completion of the task either by pressing a key or by releasing it. In two other groups Ss made a key press response that was unrelated to the cognitive task. No key press was required of a fifth group. Results indicated some apparent effect of muscle activity on pupil size during the imagery task and the findings were discussed in relation to other variables affecting pupillary activity.