Elucidating Memory Distortions in the Consolidation Process

Overview

Memories are not exact replicas of past events; they are influenced by prior knowledge and experiences, causing distortions that affect all humans. Although the reconstructive nature of memory is well studied, it remains unclear whether distortions arise d uring the encoding or retrieval stages of memory consolidation, the two phases where memories are actively processed. To address this, two experiments were conducted to identify when distortions occur and explore strategies to mitigate them. In Experiment 1, human participants memorized image locations on a novel 2D grid task. During encoding, two groups of images were learned: a pre -cluster group learned without a distorting agent, and a post-cluster group learned with knowledge of categorical clustering. Paired t-tests revealed a significant magnitude of distortions in both groups (p < 0.01) but no difference between pre- and post-clustering distortions. This suggests that encoding is not a critical period for memory distortions; they likely arise during retrieval. In Experiment 2, Transcranial Magnetic Stimulation (TMS), a non-invasive brain stimulation technique, was applied to the Anterior Temporal Lobe (ATL), a brain region involved in integrating categorical schema. Participants performed the memory task from Experiment 1 in two groups with TMS before encoding and before retrieval. Paired t -tests showed that only TMS applied pre -retrieval significantly reduced distortions (p < 0.05). Th is finding provides concrete evidence that distortions occur during retrieval, supporting Experiment 1, and shows that the neuromodulation of the ATL can mitigate them. This research offers novel insights into memory and practical pathways for addressing memory distortions in real-world situations.