Transient medial prefrontal perturbation reduces false memory formation

Abstract

Knowledge extracted across previous experiences, or schemas, benefit encoding and retention of congruent information. However, they can also reduce specificity and augment memory for semantically related, but false information. A demonstration of the latter is given by the Deese-Roediger-McDermott (DRM) paradigm, where the studying of words that fit a common semantic schema are found to induce false memories for words that are congruent with the given schema, but were not studied. The medial prefrontal cortex (mPFC) has been ascribed the function of leveraging prior knowledge to influence encoding and retrieval, based on imaging and patient studies. Here, we used transcranial magnetic stimulation (TMS) to transiently perturb ongoing mPFC processing immediately before participants performed the DRM-task. We observed the predicted reduction in false recall of critical lures after mPFC perturbation, compared to two control groups, whereas veridical recall and recognition memory performance remained similar across groups. These data provide initial causal evidence for a role of the mPFC in biasing the assimilation of new memories and their consolidation as a function of prior knowledge.

Characterization of brain network supporting episodic memory in the absence of one medial temporal lobe

“…Recent studies that have reported on the memory modulation effect after applying mPFC stimulation in animals (Liu, Jain, Vyas, & Lim, 2015) and humans (Berkers et al, 2017) partly support the feasibility of our suggestion. Recent studies that have reported on the memory modulation effect after applying mPFC stimulation in animals (Liu, Jain, Vyas, & Lim, 2015) and humans (Berkers et al, 2017) partly support the feasibility of our suggestion.…”

“…Considering the strong functional connections between the mPFC and other multiple memory-related brain areas in our MTLR patients with a normal memory function, we suggest that the mPFC could be a novel target for brain stimulation in people with MTL-dysfunctionrelated memory disturbance. Recent studies that have reported on the memory modulation effect after applying mPFC stimulation in animals (Liu, Jain, Vyas, & Lim, 2015) and humans (Berkers et al, 2017) partly support the feasibility of our suggestion.…”

The influence of transcranial magnetic stimulation of the medial prefrontal cortex on emotional memory schemas

“…sleep). The mPFC can be inhibited by continuous theta burst (cTBS) stimulation, leading to a reduction in false recall of critical lures (19), in line with studies on mPFC lesioned patients (18). Note however that these findings are related to knowledge structures in general and it remains to be investigated how these findings transfer to emotional memory.…”

“…These findings indicate the necessity of the mPFC for schematic memory formation. In support of the causal role of the mPFC in schema memory formation, a recent neurostimulation study (19) used transient magnetic stimulation (TMS) to perturb medial prefrontal processing before the performance of a Deese-Roedinger-McDermott (DRM) task (20). In this false memory task, participants are presented with lists of semantically related words (e.g.…”

“…However, these three components have as of yet not been integrated. To provide further evidence for this relationship, we sought to perturb schema memory processing using neuronavigated medial prefrontal stimulation, in line with a recent neurostimulation study (19). In a sample of 40 healthy participants, we used a validated experimental approach for negative mood induction (44) to activate negative schema processing as an experimental model of depressed state.…”