QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

HOME  |   SEARCH  |   ARCHIVE  |   SUBSCRIBE  |   CONTACT  |   HELP

The Journal of Neuroscience, March 26, 2008, 28(13):3415-3426; doi:10.1523/JNEUROSCI.2743-07.2008

This Article Full Text Full Text (PDF) Submit an eLetter Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Sadagopan, S. Articles by Wang, X. Search for Related Content PubMed PubMed Citation Articles by Sadagopan, S. Articles by Wang, X.

 Previous Article  |  Next Article 

Behavioral/Systems/Cognitive
Level Invariant Representation of Sounds by Populations of Neurons in Primary Auditory Cortex

Srivatsun Sadagopan and Xiaoqin Wang

Laboratory of Auditory Neurophysiology, Departments of Neuroscience and Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205

Correspondence should be addressed to Srivatsun Sadagopan or Xiaoqin Wang, Johns Hopkins University School of Medicine, 720 Rutland Avenue, 412 Traylor, Baltimore, MD 21205. Email: vatsun{at}jhu.edu or Email: xiaoqin.wang{at}jhu.edu

A fundamental feature of auditory perception is the constancy of sound recognition over a large range of intensities. Although this invariance has been described in behavioral studies, the underlying neural mechanism is essentially unknown. Here we show a putative level-invariant representation of sounds by populations of neurons in primary auditory cortex (A1) that may provide a neural basis for the behavioral observations. Previous studies reported that pure-tone frequency tuning of most A1 neurons widens with increasing sound level. In sharp contrast, we found that a large proportion of neurons in A1 of awake marmosets were narrowly and separably tuned to both frequency and sound level. Tuning characteristics and firing rates of the neural population were preserved across all tested sound levels. These response properties lead to a level-invariant representation of sounds over the population of A1 neurons. Such a representation is an important step for robust feature recognition in natural environments.

Key words: primary auditory cortex; frequency tuning; level invariance; neural coding; awake primate; marmoset

---

Received June 16, 2007; revised Feb. 20, 2008; accepted Feb. 20, 2008.

Correspondence should be addressed to Srivatsun Sadagopan or Xiaoqin Wang, Johns Hopkins University School of Medicine, 720 Rutland Avenue, 412 Traylor, Baltimore, MD 21205. Email: vatsun{at}jhu.edu or Email: xiaoqin.wang{at}jhu.edu

This article has been cited by other articles:

				J. de la Rocha, C. Marchetti, M. Schiff, and A. D. Reyes Linking the Response Properties of Cells in Auditory Cortex with Network Architecture: Cotuning versus Lateral Inhibition J. Neurosci., September 10, 2008; 28(37): 9151 - 9163. [Abstract] [Full Text] [PDF]

Home  |   Search  |   Archive  |   Subscribe  |   Contact  |   Help