Short-term retention during a simultaneous detection task

Subjects were required to perform a short-term memory task and a signal detection task, both individually and simultaneously. Memory performance was impaired only when the signals in the detection task were difficult to detect. The impairment in memory was restricted to items which appeared in the early positions of the list to be remembered. Detection performance was unaffected by the simultaneous task requirement and there was no correlation between performance on the two tasks when both were performed together. The results suggest that the difficulties Ss have when they attempt to perform several tasks at the same time may be due to limitations in the processes responsible for storing and retrieving information rather than those involved in the perceptual analysis of the incoming material.