Remembering by the seat of your pants.

According to dual-process theories of memory, "old" responses in recognition may reflect the separate or combined effects of two states, specific recollection and feelings of nonspecific familiarity. When decisions are based on familiarity, people may attribute enhanced perceptual fluency to memory for prior occurrence. In this experiment, we tested whether a subliminal somatic cue (a low-amplitude buzz) could enhance feelings of familiarity. The buzz increased the likelihood that participants responded "old," both correctly and incorrectly. This effect occurred only with subjectively difficult stimuli, those relatively unlikely to elicit clear recollection. When a stronger control buzz was used, the effect vanished. Results for confidence ratings were consistent with Whittlesea's SCAPE theory, producing a dissociation between hits and false alarms. Specifically, the buzz reduced confidence in hits and increased confidence in false alarms, in accord with the most likely attributions for the feelings of familiarity associated with the buzz.