Tracking Your Mind's Eye during Recollection: Decoding the Long-Term Recall of Short Audiovisual Clips

Abstract

Unlike familiarity, recollection involves the ability to reconstruct mentally previous events that results in a strong sense of reliving. According to the reinstatement hypothesis, this specific feature emerges from the reactivation of cortical patterns involved during information exposure. Over time, the retrieval of specific details becomes more difficult, and memories become increasingly supported by familiarity judgments. The multiple trace theory (MTT) explains the gradual loss of episodic details by a transformation in the memory representation, a view that is not shared by the standard consolidation model. In this study, we tested the MTT in light of the reinstatement hypothesis. The temporal dynamics of mental imagery from long-term memory were investigated and tracked over the passage of time. Participant EEG activity was recorded during the recall of short audiovisual clips that had been watched 3 weeks, 1 day, or a few hours beforehand. The recall of the audiovisual clips was assessed using a Remember/Know/New procedure, and snapshots of clips were used as recall cues. The decoding matrices obtained from the multivariate pattern analyses revealed sustained patterns that occurred at long latencies (>500 msec poststimulus onset) that faded away over the retention intervals and that emerged from the same neural processes. Overall, our data provide further evidence toward the MTT and give new insights into the exploration of our “mind's eye.”

The fate of visual long term memories for images across weeks in adults and children

“…Second, the present study raises the question of how the different kinds of consolidation mechanisms (synaptic vs systemic), as well as how the different memory/processing systems interact during the encoding and the consolidation of visual memories 46 , 47 . General theories of memory (e.g.…”

“…Memory phenomena result in large part from both external, slow, pervasive, and cortex-based mechanisms of learning, and on transitory associative representations formed and maintained within the medial temporal lobe memory system 46 , 53 – 55 . In addition, important changes in the functional connectivity between the hippocampus and cortical areas operate during memory consolidation, especially with a progressive disengagement of the Medial Temporal Lobe and both synaptic and systemic consolidation in the neocortex 47 , 56 , 57 . How those different memory systems interact and how a redescription of knowledge operates over time and consolidation remain a challenge for further research.…”

Systems consolidation, transformation and reorganization: Multiple Trace Theory, Trace Transformation Theory and their Competitors

“…In an EEG study, Larzabal et al (2020) also used video clips but tested participants' remember/know judgements of frames from those clips at delays of hours, one day and three weeks. Using MVPA of the EEG signal to classify new and old items, they, too, found sustained patterns indicative of reinstatement effects that correlated with recollection.…”

“…Specifically, are the prestimulus neurons that were activated, or subset of them, also re-activated post-encoding, and does the latter set also support representations of detailed, remote memories? There is no definitive answer, but Larzabal et al's (2020) study tracking memory to reinstatement effects suggests that it is possible that similar neural populations are implicated at all time points. Using MVPA of the EEG signal to video clips, they found that although the signal faded over time, sustained patterns indicative of reinstatement effects were…”