Spatial contrast sensitivity of the tree shrew

Vision Res. 1984;24(9):1037-42. doi: 10.1016/0042-6989(84)90080-4.


Spatial contrast sensitivity functions (CSFs) were measured for 3 tree shrews. Our two-alternative forced-choice discrimination paradigm required the animals to discriminate a vertical sine-wave luminance grating from a homogeneous field of the same size (16 degrees) and mean luminance (35 cd/m2). Spatial frequencies tested ranged from 0.1 to 2.0 c/deg and grating contrast was varied trial-by-trial using a modified staircase technique. Small between-subject variations in the shape of the CSFs appeared to be correlated with our estimates of refractive error for each animal. In general, the CSFs were of the typical band-pass type with peak sensitivity occurring at approximately 0.7 c/deg. Estimates of grating acuity derived from the CSFs ranged from 1.2 to 2.4 c/deg and are within the limitations set by the eye size and retinal anatomy of the tree shrew.

Publication types

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

MeSH terms

  • Animals
  • Discrimination, Psychological / physiology
  • Female
  • Form Perception / physiology*
  • Male
  • Pattern Recognition, Visual / physiology*
  • Psychophysics
  • Refractive Errors / physiopathology
  • Sensory Thresholds / physiology
  • Tupaiidae / physiology*
  • Visual Acuity