Dopamine-based mechanism for transient forgetting

Nature. 2021 Mar;591(7850):426-430. doi: 10.1038/s41586-020-03154-y. Epub 2021 Jan 20.

Abstract

Active forgetting is an essential component of the memory management system of the brain1. Forgetting can be permanent, in which prior memory is lost completely, or transient, in which memory exists in a temporary state of impaired retrieval. Temporary blocks on memory seem to be universal, and can disrupt an individual's plans, social interactions and ability to make rapid, flexible and appropriate choices. However, the neurobiological mechanisms that cause transient forgetting are unknown. Here we identify a single dopamine neuron in Drosophila that mediates the memory suppression that results in transient forgetting. Artificially activating this neuron did not abolish the expression of long-term memory. Instead, it briefly suppressed memory retrieval, with the memory becoming accessible again over time. The dopamine neuron modulates memory retrieval by stimulating a unique dopamine receptor that is expressed in a restricted physical compartment of the axons of mushroom body neurons. This mechanism for transient forgetting is triggered by the presentation of interfering stimuli immediately before retrieval.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Central Nervous System / cytology
  • Central Nervous System / physiology
  • Conditioning, Psychological
  • Dendrites / physiology
  • Dopamine / metabolism*
  • Dopaminergic Neurons / physiology*
  • Drosophila Proteins / metabolism
  • Drosophila melanogaster / cytology
  • Drosophila melanogaster / physiology*
  • Electric Stimulation
  • Female
  • Memory, Long-Term / physiology
  • Mental Recall / physiology*
  • Mushroom Bodies / cytology
  • Mushroom Bodies / physiology
  • Odorants
  • Receptors, Dopamine D1 / metabolism
  • Time Factors

Substances

  • Dop1R2 protein, Drosophila
  • Drosophila Proteins
  • Receptors, Dopamine D1
  • Dopamine