title: Cortical Map Plasticity as a Function of Vagus Nerve Stimulation Intensity.
abstract: BACKGROUND
  Pairing sensory or motor events with vagus nerve stimulation (VNS) can reorganize sensory or motor cortex. Repeatedly pairing a tone with a brief period of VNS increases the proportion of primary auditory cortex (A1) responding to the frequency of the paired tone. However, the relationship between VNS intensity and cortical map plasticity is not known.
  
  
  OBJECTIVE
  The primary goal of this study was to determine the range of VNS intensities that can be used to direct cortical map plasticity.
  
  
  METHODS
  The rats were exposed to a 9 kHz tone paired with VNS at intensities of 0.4, 0.8, 1.2, or 1.6 mA.
  
  
  RESULTS
  In rats that received moderate (0.4-0.8 mA) intensity VNS, 75% more cortical neurons were tuned to frequencies near the paired tone frequency. A two-fold effective range is broader than expected based on previous VNS studies. Rats that received high (1.2-1.6 mA) intensity VNS had significantly fewer neurons tuned to the same frequency range compared to the moderate intensity group.
  
  
  CONCLUSIONS
  This result is consistent with previous results documenting that VNS is memory enhancing as a non-monotonic relationship of VNS intensity.
authors.affiliation: School of Behavioral and Brain Sciences, The University of Texas at Dallas, 800 West Campbell Road GR41, Richardson, TX 75080, USA. Electronic address: mborla1@gmail.com.
authors.forename: M S
authors.initials: MS
authors.lastname: Borland
authors.affiliation: School of Behavioral and Brain Sciences, The University of Texas at Dallas, 800 West Campbell Road GR41, Richardson, TX 75080, USA.
authors.forename: W A
authors.initials: WA
authors.lastname: Vrana
authors.affiliation: School of Behavioral and Brain Sciences, The University of Texas at Dallas, 800 West Campbell Road GR41, Richardson, TX 75080, USA.
authors.forename: N A
authors.initials: NA
authors.lastname: Moreno
authors.affiliation: School of Behavioral and Brain Sciences, The University of Texas at Dallas, 800 West Campbell Road GR41, Richardson, TX 75080, USA.
authors.forename: E A
authors.initials: EA
authors.lastname: Fogarty
authors.affiliation: School of Behavioral and Brain Sciences, The University of Texas at Dallas, 800 West Campbell Road GR41, Richardson, TX 75080, USA.
authors.forename: E P
authors.initials: EP
authors.lastname: Buell
authors.affiliation: School of Behavioral and Brain Sciences, The University of Texas at Dallas, 800 West Campbell Road GR41, Richardson, TX 75080, USA.
authors.forename: P
authors.initials: P
authors.lastname: Sharma
authors.affiliation: School of Behavioral and Brain Sciences, The University of Texas at Dallas, 800 West Campbell Road GR41, Richardson, TX 75080, USA.
authors.forename: C T
authors.initials: CT
authors.lastname: Engineer
authors.affiliation: School of Behavioral and Brain Sciences, The University of Texas at Dallas, 800 West Campbell Road GR41, Richardson, TX 75080, USA.
authors.forename: M P
authors.initials: MP
authors.lastname: Kilgard
mesh_terms: D000818:Animals; D001303:Auditory Cortex / Q000502:physiology*; D001931:Brain Mapping; D005260:Female; D009044:Motor Cortex / Q000502:physiology*; D009473:Neuronal Plasticity; D051381:Rats; D017207:Rats, Sprague-Dawley; D055536:Vagus Nerve Stimulation
keywords: Auditory cortex; Inverted U function; Plasticity; Vagal nerve stimulation