• DOI:10.1093/CERCOR/8.2.125
• Corpus ID: 9076039

The posterior field P of cat auditory cortex: coding of envelope transients.

@article{Heil1998ThePF,
  title={The posterior field P of cat auditory cortex: coding of envelope transients.},
  author={Peter Heil and Dexter R F Irvine},
  journal={Cerebral cortex},
  year={1998},
  volume={8 2},
  pages={
          125-41
        }
}

• P. Heil, D. Irvine
• Published 1 March 1998
• Physics
• Cerebral cortex

The posterior field (P) of the cat auditory cortex contains a very high proportion of neurons whose responses change non-monotonically with the sound pressure level (SPL) of tonal stimuli, leading to circumscribed frequency-SPL response areas, and it has therefore been suggested that field P may be specialized for processing of sound intensity. We demonstrate here a great diversity of response areas in field P. Furthermore, by varying tone SPL and rise time, we show that, as in primary auditory cortex (AI), the onset response of a field P neuron is better described as a function of the instantaneous peak pressure (envelope) at the time of response generation than of the steady-state SPL of the stimulus. Such responses could be used to track transients or represent envelopes in more general terms, rather than to code SPL. Compared with AI, field P neurons have relatively long minimum latencies along with a large jitter in spike timing. Tracking would therefore be most effective for slowly varying envelopes, and one function of the inhibition that generates non-monotonicity in field P may be to suppress temporally sluggish responses to rapid transients, such as the onsets of high-SPL, short rise time tones. Field P may thus be specialized for coding slowly varying signals.