CROSS-TASK CROSS-TALK IN MEMORY AND PERCEPTION

The application of the additive factors method depends on finding fact ors that selectively influence processing stages. When all the process es for a task are in series, a factor directly influencing a process m ight change its output and thereby have indirect influence on succeedi ng processes. We investigate whether such indirect influence is possib le between processes associated with different tasks being performed t ogether. In two dual-task memory scanning and arithmetic experiments w ith digits as the stimuli for both tasks, information relevant for onl y one of the tasks nonetheless affected performance of the other. When the same digit was relevant for the two tasks, cross-task facilitatio n and interference were observed in some cases. Displaying the same di git for both tasks led to relatively fast response times, paralleling the effect of flankers in the response competition paradigm. But repet ition of digits in memory slowed responses. It is suggested that the n eed for control processes to keep task information segregated is respo nsible for the pattern of effects.