Tactile hyperacuity thresholds correlate with finger maps in primary somatosensory cortex (S1)

Cereb Cortex. 2007 Dec;17(12):2878-91. doi: 10.1093/cercor/bhm015. Epub 2007 Mar 19.


Behavioral tactile discrimination thresholds were compared with functional magnetic resonance imaging measurements of cortical finger representations within primary somatosensory cortex (S1) for 10 human subjects to determine whether cortical magnification in S1 could account for the variation in tactile hyperacuity thresholds of the fingers. Across 10 subjects, the increase in tactile thresholds from the index finger to the little finger correlated with the decrease in cortical representation across fingers in S1. Additionally, representations of the fingers within S1, in Brodmann areas 3b and 1, were also correlated with the thresholds. These results suggest that tactile hyperacuity is largely determined by the cortical representation of the fingers in S1.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adolescent
  • Adult
  • Brain Mapping*
  • Differential Threshold / physiology*
  • Evoked Potentials, Somatosensory / physiology*
  • Female
  • Fingers / innervation
  • Fingers / physiology*
  • Humans
  • Male
  • Physical Stimulation / methods
  • Sensory Thresholds / physiology*
  • Statistics as Topic
  • Touch / physiology*