The trigger mechanism of the target detection task influencing recognition memory at Stimulus Onset Asynchrony of...

Individuals showed better memory performance for target-paired items compared to distractor-paired items during sequential target detection and memory encoding tasks, a phenomenon called target-paired memory enhancement (TPME). The TPME was considered to be triggered by the response when the detection stimulus preceded the memory item by 0.5 s without temporal overlap. However, this hypothesis has not been empirically verified. To test the hypothesis, we instructed participants to detect the target colour before memorizing words, varying the response requirements for the target colour across different tasks. Participants responded only to the target colour in the Go-target-0.5 s task (SOA = 0.5 s) and Go-target-1 s task (SOA = 1 s), to distractor colours in the No-Go-target task, and to all colours with different keys in the response-choice task. The results of the remember-know recognition test showed that TPME was consistent across all tasks for R responses, but only occurred in the Go-target-0.5 s task for corrected K responses. These results suggested that both target detection and response can independently contribute to TPME when the detection stimulus and the memory item were presented successively without temporal overlap. The target detection enhanced recollection and familiarity, while the response enhanced familiarity. The effect on recollection was lasting, while the effect on familiarity was transient.