Pre-neuronal morphological processing of object location by individual whiskers

Nat Neurosci. 2013 May;16(5):622-31. doi: 10.1038/nn.3378. Epub 2013 Apr 7.

Abstract

In the vibrissal system, touch information is conveyed by a receptorless whisker hair to follicle mechanoreceptors, which then provide input to the brain. We examined whether any processing, that is, meaningful transformation, occurs in the whisker itself. Using high-speed videography and tracking the movements of whiskers in anesthetized and behaving rats, we found that whisker-related morphological phase planes, based on angular and curvature variables, can represent the coordinates of object position after contact in a reliable manner, consistent with theoretical predictions. By tracking exposed follicles, we found that the follicle-whisker junction is rigid, which enables direct readout of whisker morphological coding by mechanoreceptors. Finally, we found that our behaving rats pushed their whiskers against objects during localization in a way that induced meaningful morphological coding and, in parallel, improved their localization performance, which suggests a role for pre-neuronal morphological computation in active vibrissal touch.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Afferent Pathways / physiology*
  • Analysis of Variance
  • Anesthetics / pharmacology
  • Animals
  • Biomechanical Phenomena
  • Brain Mapping*
  • Hair Follicle / physiology*
  • Male
  • Mechanoreceptors / physiology*
  • Movement / physiology*
  • Physical Stimulation
  • Rats
  • Rats, Wistar
  • Reproducibility of Results
  • Time Factors
  • Vibrissae / innervation*
  • Video Recording
  • Wakefulness

Substances

  • Anesthetics