Topographic Distribution of Stimulus-Specific Adaptation across Auditory Cortical Fields in the Anesthetized Rat

PLoS Biol. 2016 Mar 7;14(3):e1002397. doi: 10.1371/journal.pbio.1002397. eCollection 2016 Mar.

Abstract

Stimulus-specific adaptation (SSA) in single neurons of the auditory cortex was suggested to be a potential neural correlate of the mismatch negativity (MMN), a widely studied component of the auditory event-related potentials (ERP) that is elicited by changes in the auditory environment. However, several aspects on this SSA/MMN relation remain unresolved. SSA occurs in the primary auditory cortex (A1), but detailed studies on SSA beyond A1 are lacking. To study the topographic organization of SSA, we mapped the whole rat auditory cortex with multiunit activity recordings, using an oddball paradigm. We demonstrate that SSA occurs outside A1 and differs between primary and nonprimary cortical fields. In particular, SSA is much stronger and develops faster in the nonprimary than in the primary fields, paralleling the organization of subcortical SSA. Importantly, strong SSA is present in the nonprimary auditory cortex within the latency range of the MMN in the rat and correlates with an MMN-like difference wave in the simultaneously recorded local field potentials (LFP). We present new and strong evidence linking SSA at the cellular level to the MMN, a central tool in cognitive and clinical neuroscience.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptation, Physiological*
  • Animals
  • Auditory Cortex / physiology*
  • Female
  • Neurons / physiology
  • Rats, Long-Evans

Grant support

This work was funded by Spanish MINECO (Grant BFU2013-43608-P to MSM), Spanish JCYL (Grant JCYL-SA343-U14 to MSM) and the European Social Fund/Spanish JCYL (Ph.D. Fellowship to JND under the Operational Programme ESF Castilla y León 2007–2013). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.