A recurrent circuit implements normalization, simulating the dynamics of V1 activity

David J. Heeger, Klavdia O. Zemlianova

Research output: Contribution to journalArticlepeer-review


The normalization model has been applied to explain neural activity in diverse neural systems including primary visual cortex (V1). The model's defining characteristic is that the response of each neuron is divided by a factor that includes a weighted sum of activity of a pool of neurons. Despite the success of the normalization model, there are three unresolved issues. 1) Experimental evidence supports the hypothesis that normalization in V1 operates via recurrent amplification, i.e., amplifying weak inputs more than strong inputs. It is unknown how normalization arises from recurrent amplification. 2) Experiments have demonstrated that normalization is weighted such that each weight specifies how one neuron contributes to another's normalization pool. It is unknown how weighted normalization arises from a recurrent circuit. 3) Neural activity in V1 exhibits complex dynamics, including gamma oscillations, linked to normalization. It is unknown how these dynamics emerge from normalization. Here, a family of recurrent circuit models is reported, each of which comprises coupled neural integrators to implement normalization via recurrent amplification with arbitrary normalization weights, some of which can recapitulate key experimental observations of the dynamics of neural activity in V1.

Original languageEnglish (US)
Pages (from-to)22494-22505
Number of pages12
JournalProceedings of the National Academy of Sciences of the United States of America
Issue number36
StatePublished - Sep 8 2020


  • Computational neuroscience
  • Gamma oscillation
  • Normalization
  • Recurrent neural network
  • V1

ASJC Scopus subject areas

  • General


Dive into the research topics of 'A recurrent circuit implements normalization, simulating the dynamics of V1 activity'. Together they form a unique fingerprint.

Cite this