Physiological evidence for auditory modulation filterbanks: cortical responses to concurrent modulations

J Acoust Soc Am. 2013 Jan;133(1):EL7-12. doi: 10.1121/1.4769400.

Abstract

Modern psychophysical models of auditory modulation processing suggest that concurrent auditory features with syllabic (~5 Hz) and phonemic rates (~20 Hz) are processed by different modulation filterbank elements, whereas features at similar modulation rates are processed together by a single element. The neurophysiology of concurrent modulation processing at speech-relevant rates is here investigated using magnetoencephalography. Results demonstrate expected neural responses to stimulus modulation frequencies; nonlinear interaction frequencies are also present, but, critically, only for nearby rates, analogous to "beating" in a cochlear filter. This provides direct physiological evidence for modulation filterbanks, allowing separate processing of concurrent syllabic and phonemic modulations.

Publication types

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

MeSH terms

  • Acoustic Stimulation
  • Auditory Cortex / physiology*
  • Evoked Potentials, Auditory
  • Female
  • Humans
  • Magnetoencephalography
  • Male
  • Nonlinear Dynamics
  • Phonetics*
  • Psychoacoustics
  • Speech Acoustics
  • Speech Intelligibility
  • Speech Perception*
  • Time Factors
  • Young Adult