The organization of somatosensory area II in tree shrews

J Comp Neurol. 1981 Sep 1;201(1):121-33. doi: 10.1002/cne.902010109.


Microelectrode multiunit recording methods were used to determine the somatotopic organization of the second somatosensory area, S-II, in tree shrews. Neurons were activated by light tactile stimuli, and receptive fields were located on the contralateral body surface only. The orientation of S-II was such that the top of the head adjoined S-I and the distal limbs pointed away from S-I so that the representation could be characterized as "erect". In general, the distortions of the body surface in S-II were similar to those found in S-I of the tree shrew (Sur et al., '80), with the exception that proportionately less cortex was devoted to the glabrous nose. The representation in S-II was more continuous than that in S-I. Finally, cortex bordering S-II caudally was found to be responsive to generally more intense somatosensory stimuli such as taps to the body surface.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Brain Mapping
  • Evoked Potentials, Somatosensory
  • Face / innervation
  • Forelimb / innervation
  • Hindlimb / innervation
  • Mechanoreceptors / physiology
  • Neural Pathways / physiology
  • Neurons / physiology
  • Somatosensory Cortex / physiology*
  • Touch / physiology
  • Tupaia