Contextual Inference Drives Motor Memory Protection and Disruption
Newly acquired memories are initially fragile and are consolidated into long-term memory over time. Although consolidated memories were once thought to be resistant to interference, accumulating evidence shows that memory reactivation renders them transiently labile, making them susceptible to modification or interference before reconsolidation. Crucially, however, there is substantial variation…
Memory is a fragile process, constantly evolving over time. Once formed, it can be modified or disrupted by new information. However, not all reactivated memories are equally susceptible to this modification. To understand what factors influence this vulnerability, researchers examined motor memory interference using a classic A-B-A visuomotor rotation paradigm.
Participants first adapted to a 30-degree clockwise rotation on Day 1. On Day 2, an interfering 30-degree counter-clockwise rotation was introduced under several conditions. These included introducing the interference directly without reactivating the original memory, after a brief reactivation of the original rotation, after expressing the original memory without feedback, or following a gradual transition from the original to the interfering rotation.
Interestingly, the researchers found that reactivating the original memory before introducing the interfering rotation actually protected it. This protection was evident during relearning on Day 3. On the other hand, introducing the interference directly without reactivation disrupted the original memory. This protective effect appeared to be consistent with a contextual-inference account.
A large sensory prediction error experienced during the abrupt transition from the original to the interfering rotation served as a latent contextual cue. This cue signaled a new context and shielded the original memory from being overwritten.
However, this protective effect could be abolished if the prediction error was eliminated. This could be done through an immediate washout session with a similar error profile or through a gradual transition from the original to the interfering rotation. Furthermore, when explicit contextual cues distinguished between the two perturbations, the memories remained protected even in the absence of a salient prediction error.
These findings suggest that the fate of a consolidated memory—whether it is modified or protected—depends on the availability of explicit cues or latent signals such as sensory prediction error when interference is introduced.
Written by urgent.news from bioRxiv's reporting — not their text. Machine-written — may contain errors; check the original before relying on it.
