Encoding focus does not affect recollection of action memories: Event related potential (ERP) and modeling evidence

Prior work using word stimuli has uncovered evidence that encoding focus (i.e., self-focus or other-focus) alters non-diagnostic recollection and the putative ERP correlate of recollection (i.e., the Late Positive Component or LPC; Leynes and Mok, 2017, Brain & Cognition). The present study examined the generality of these effects by testing memory for actions. Participants viewed videos of either a male actor or female actor completing simple actions (e.g., Ride the Elevator; Climb the Stairs). Participants judged how much fun it would be to personally perform the action under the self-focus encoding condition, whereas they rated how much fun the actor had while performing the action in the other-focus encoding condition. At test, participants made source judgments regarding who (i.e., male or female) performed the action. Self- and other-focus encoding had similar effects on all behavioral measures including parameters from Dual Process Signal Detection and Unequal Variance Signal Detection models. Experiment 2 recorded brain activity (event-related potentials) and found that self- and other-focus encoding produced similar recognition and LPC amplitudes. These results suggest that encoding focus did not affect the amount of non-diagnostic recollection because both action types promoted strong recollection. Such results are additional evidence that action memory creates more complex traces as compared with typical lab-based stimuli (i.e., pictures or words) and identifies an important boundary condition for encoding focus effects on recollection.