Waking State: Rapid Variations Modulate Neural and Behavioral Responses

Neuron. 2015 Sep 23;87(6):1143-1161. doi: 10.1016/j.neuron.2015.09.012.


The state of the brain and body constantly varies on rapid and slow timescales. These variations contribute to the apparent noisiness of sensory responses at both the neural and the behavioral level. Recent investigations of rapid state changes in awake, behaving animals have provided insight into the mechanisms by which optimal sensory encoding and behavioral performance are achieved. Fluctuations in state, as indexed by pupillometry, impact both the "signal" (sensory evoked response) and the "noise" (spontaneous activity) of cortical responses. By taking these fluctuations into account, neural response (co)variability is significantly reduced, revealing the brain to be more reliable and predictable than previously thought.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Action Potentials / physiology
  • Animals
  • Brain / physiology*
  • Humans
  • Motor Activity / physiology*
  • Nerve Net / physiology*
  • Neurons / physiology*
  • Time Factors
  • Wakefulness / physiology*