Slip-Based Coding of Local Shape and Texture in Mouse S1

Neuron. 2018 Jan 17;97(2):418-433.e5. doi: 10.1016/j.neuron.2017.12.021. Epub 2018 Jan 4.


Tactile objects have both local geometry (shape) and broader macroscopic texture, but how these different spatial scales are simultaneously encoded during active touch is unknown. In the whisker system, we tested for a shared code based on localized whisker micromotions (stick-slips) and slip-evoked spikes. We trained mice to discriminate smooth from rough surfaces, including ridged gratings and sandpaper. Whisker slips locked to ridges and evoked temporally precise spikes (<10 ms jitter) in somatosensory cortex (S1) that could resolve ridges with ∼1 mm accuracy. Slip-sensitive neurons also encoded touch and texture. On rough surfaces, both slip-evoked spikes and an additional non-slip signal elevated mean firing rate, allowing accurate rough-smooth texture decoding from population firing rate. Eighteen percent of neurons were selective among rough surfaces. Thus, slips elicit spatially and temporally precise spiking in S1 that simultaneously encodes local shape (ridges) and is integrated into a macroscopic firing rate code for roughness.

Keywords: S1 cortex; active sensation; barrel cortex; multiplexed code; neural coding; shape; spatial tuning; stick-slip; texture; virtual foraging.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Action Potentials
  • Animals
  • Cues
  • Discrimination, Psychological / physiology
  • Mice
  • Motion
  • Neurons / physiology*
  • Somatosensory Cortex / physiology*
  • Surface Properties
  • Time Factors
  • Touch / physiology
  • Touch Perception / physiology*
  • Vibrissae / innervation
  • Vibrissae / physiology*