Cortical interference effects in the cocktail party problem

Nat Neurosci. 2007 Dec;10(12):1601-7. doi: 10.1038/nn2009. Epub 2007 Nov 11.


Humans and animals must often discriminate between complex natural sounds in the presence of competing sounds (maskers). Although the auditory cortex is thought to be important in this task, the impact of maskers on cortical discrimination remains poorly understood. We examined neural responses in zebra finch (Taeniopygia guttata) field L (homologous to primary auditory cortex) to target birdsongs that were embedded in three different maskers (broadband noise, modulated noise and birdsong chorus). We found two distinct forms of interference in the neural responses: the addition of spurious spikes occurring primarily during the silent gaps between song syllables and the suppression of informative spikes occurring primarily during the syllables. Both effects systematically degraded neural discrimination as the target intensity decreased relative to that of the masker. The behavioral performance of songbirds degraded in a parallel manner. Our results identify neural interference that could explain the perceptual interference at the heart of the cocktail party problem.

Publication types

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

MeSH terms

  • Acoustic Stimulation / methods
  • Action Potentials / physiology
  • Analysis of Variance
  • Animals
  • Auditory Cortex / cytology*
  • Behavior, Animal
  • Conditioning, Operant
  • Discrimination, Psychological / physiology*
  • Dose-Response Relationship, Radiation
  • Finches
  • Male
  • Neurons / physiology*
  • Pattern Recognition, Physiological / physiology
  • Perceptual Masking / physiology*
  • Psychometrics
  • Sound*
  • Vocalization, Animal / physiology*