Central Gain Restores Auditory Processing following Near-Complete Cochlear Denervation

Neuron. 2016 Feb 17;89(4):867-79. doi: 10.1016/j.neuron.2015.12.041. Epub 2016 Jan 28.


Sensory organ damage induces a host of cellular and physiological changes in the periphery and the brain. Here, we show that some aspects of auditory processing recover after profound cochlear denervation due to a progressive, compensatory plasticity at higher stages of the central auditory pathway. Lesioning >95% of cochlear nerve afferent synapses, while sparing hair cells, in adult mice virtually eliminated the auditory brainstem response and acoustic startle reflex, yet tone detection behavior was nearly normal. As sound-evoked responses from the auditory nerve grew progressively weaker following denervation, sound-evoked activity in the cortex-and, to a lesser extent, the midbrain-rebounded or surpassed control levels. Increased central gain supported the recovery of rudimentary sound features encoded by firing rate, but not features encoded by precise spike timing such as modulated noise or speech. These findings underscore the importance of central plasticity in the perceptual sequelae of cochlear hearing impairment.

Publication types

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

MeSH terms

  • Acoustic Stimulation / methods
  • Action Potentials / drug effects
  • Action Potentials / physiology
  • Analysis of Variance
  • Animals
  • Auditory Pathways / physiology*
  • Auditory Threshold / physiology
  • Cochlea / injuries
  • Cochlea / metabolism
  • Cochlea / physiopathology*
  • Denervation
  • Enzyme Inhibitors / pharmacology
  • Enzyme Inhibitors / therapeutic use
  • Functional Laterality
  • Hair Cells, Auditory / physiology
  • Male
  • Mice
  • Mice, Inbred CBA
  • Neurofilament Proteins / metabolism
  • Otoacoustic Emissions, Spontaneous / physiology*
  • Ouabain / pharmacology
  • Ouabain / therapeutic use
  • Receptors, AMPA / metabolism
  • Reflex, Startle / physiology*


  • Enzyme Inhibitors
  • Neurofilament Proteins
  • Receptors, AMPA
  • neurofilament protein H
  • Ouabain
  • glutamate receptor ionotropic, AMPA 2