Stimulus and response priming in rapid serial visual presentation: evidence for a dissociation

Two experiments investigated the capacity demands of stimulus and response priming in a rapid serial visual presentation (RSVP) task. Three targets were presented in a stream of visual symbols: The first two (T1 and T2) required an unspeeded manual response at the end of the trial, but the third (T3) called for an immediate,speeded manual response. T2 and T3 either were identical (fully compatible), required the same response (response compatible), or required different responses (incompatible). Priming in the fully compatible condition depended strongly on successful identification of the priming stimulus, whereas response-based priming was observed regardless of whether the prime could be reported or not. These findings suggest that stimulus coding and response coding are automatic processes, unaffected by attentional capacity constraints, followed by capacity-limited stimulus consolidation and response selection. Moreover, even though response codes are activated automatically upon stimulus processing, both types of codes act, and affect behavior, independently.