Altered Human Memory Modification in the Presence of Normal Consolidation

Abstract

Following initial learning, the memory is stabilized by consolidation mechanisms, and subsequent modification of memory strength occurs via reconsolidation. Yet, it is not clear whether consolidation and memory modification are the same or different systems-level processes. Here, we report disrupted memory modification in the presence of normal consolidation of human motor memories, which relate to differences in lesioned brain structure after stroke. Furthermore, this behavioral dissociation was associated with macrostructural network architecture revealed by a graph-theoretical approach, and with white-matter microstructural integrity measured by diffusion-weighted MRI. Altered macrostructural network architecture and microstructural integrity of white-matter underlying critical nodes of the related network predicted disrupted memory modification. To the best of our knowledge, this provides the first evidence of mechanistic differences between consolidation, and subsequent memory modification through reconsolidation, in human procedural learning. These findings enable better understanding of these memory processes, which may guide interventional strategies to enhance brain function and resulting behavior.

Cerebral Activity Associated with Transient Sleep-Facilitated Reduction in Motor Memory Vulnerability to Interference

“…We therefore argue that consolidation and reconsolidation processes share common and interacting mechanisms (but see ref. 32 ); however, note that the present study was not designed to test this particular hypothesis and that this interpretation does not explain the discrepancies between the present results and our previous research 11 . Future research should also characterize whether the pattern of results observed in the present study at 24 h is triggered by the 8 h (potentially reactivation) session or whether, as suggested in previous research 4 , the restorative effect of nocturnal sleep can be observed without reactivation.…”

Reward disrupts reactivated human skill memory

“…Retention was defined as the difference in performance between Day 3 and the last 3 trials of Day 1. As in previous studies using the same task, to better characterize memory strength by minimizing motor fatigue-related decrements in performance, the best two trials were considered for Day 1 post-training and for Day 3 memory strength 45 46 . Two tailed tests were used in all analyses.…”

Effects of tDCS on motor learning and memory formation: A consensus and critical position paper

“…Each time a given skill is executed, retrieval of these previously consolidated motor memories may initiate a cascade of plasticity mechanisms that enable their composition to be modified in order to maintain skill performance optimization over the long term (Censor, Buch, Nader, & Cohen, 2015;Censor, Dayan, & Cohen, 2014;Censor, Dimyan, & Cohen, 2010;Censor, Horovitz, & Cohen, 2014;Dayan, Laor-Maayany, & Censor, 2016;Wymbs et al, 2016). It has been reported that existing motor memories can be modified through reconsolidation, which may repeat as needed across the lifespan (Censor, Horovitz, et al, 2014;Sandrini, Censor, Mishoe, & Cohen, 2013;Wymbs et al, 2016).…”