The Biology of Forgetting-A Perspective

Neuron. 2017 Aug 2;95(3):490-503. doi: 10.1016/j.neuron.2017.05.039.


Pioneering research studies, beginning with those using Drosophila, have identified several molecular and cellular mechanisms for active forgetting. The currently known mechanisms for active forgetting include neurogenesis-based forgetting, interference-based forgetting, and intrinsic forgetting, the latter term describing the brain's chronic signaling systems that function to slowly degrade molecular and cellular memory traces. The best-characterized pathway for intrinsic forgetting includes "forgetting cells" that release dopamine onto engram cells, mobilizing a signaling pathway that terminates in the activation of Rac1/Cofilin to effect changes in the actin cytoskeleton and neuron/synapse structure. Intrinsic forgetting may be the default state of the brain, constantly promoting memory erasure and competing with processes that promote memory stability like consolidation. A better understanding of active forgetting will provide insights into the brain's memory management system and human brain disorders that alter active forgetting mechanisms.

Keywords: Rac1; active forgetting; consolidation; dopamine; hippocampal neurogenesis; intrinsic forgetting; memory.

Publication types

  • Review

MeSH terms

  • Animals
  • Brain / physiology
  • Humans
  • Memory / physiology*
  • Memory Disorders / physiopathology*
  • Neurogenesis / physiology*
  • Neurons / metabolism*
  • Synapses / metabolism*