Sham-controlled trial reveals brain stimulation attenuates self-referential memory advantages in healthy adults, indicating distinct cortical roles in social episodic processing.
Key Points
To determine the causal contributions of the dorsomedial prefrontal cortex (dmPFC) and posterior parietal cortex (PPC) to self-referential episodic memory, source memory, and metacognition.
Enrolled 100 participants in an incidental encoding task evaluating trait adjectives for the self, a close friend, or a celebrity under anodal or sham focal transcranial direct current stimulation (tDCS) targeting either dmPFC or PPC.
Evaluated item and source memory sensitivity (d′) alongside metacognitive efficiency (meta-d′/d′) across agent categories and emotional valence during subsequent recognition testing.
Confirmed a baseline graded memory advantage for self-related information across item memory, source memory, and metacognitive efficiency compared to close and distant others.
Demonstrated that anodal tDCS to either the dmPFC or PPC attenuated the classic self-reference effect in episodic memory.
Observed that PPC stimulation uniquely biased source memory retrieval away from positive information and toward negative information.