Informative and uninformative prestimulus cues at encoding benefit familiarity and source memory

Research using both neuroimaging and psychophysiology show that neural activity elicited by an informative prestimulus cue predicts subsequent memory. However, it remains unclear whether prestimulus encoding cues benefit subsequent memory performance. At encoding, participants made one of two semantic judgments on words preceded by an informative prestimulus cue that identified the upcoming semantic judgment, an uninformative prestimulus cue that signaled an upcoming trial but no information about the semantic judgment, or no cue. We observed that prestimulus cues affected multiple mnemonic processes. Specifically, dual process estimates of familiarity demonstrated a graded pattern with the informativeness of the prestimulus cues (i.e., informative > uninformative > no cues). Moreover, both informative and uninformative prestimulus cues enhanced subsequent source memory accuracy for the encoding task compared to the no cue condition. There was no evidence that prestimulus cues affected estimates of recollection derived from confidence-based receiver operating characteristic curves. These findings suggest that prestimulus cues can strengthen the processes that support successful memory encoding and benefit subsequent familiarity and source memory. The findings also suggest that prestimulus subsequent memory effects induced by prestimulus cues reflect the mobilization of multiple processes associated with successful memory encoding.