Advertisement

Journal of comparative physiology

, Volume 136, Issue 4, pp 291–299 | Cite as

Visual sensitivity of ground squirrels to spatial and temporal luminance variations

  • Gerald H. Jacobs
  • Barbara Blakeslee
  • Mark E. McCourt
  • R. B. H. Tootell
Article

Summary

We have investigated the visual sensitivity of the California ground squirrel (Speromphilus beecheyi) to spatial and temporal luminance patterns. Spatial contrast sensitivity functions were determined in behavioral discrimination experiments in which the stimuli were sinusoidally-modulated luminance gratings. These squirrels were found to be maximally sensitive to spatial frequencies of about 0.7 cycles/ degree (c/d), and they are unable to discriminate gratings whose frequencies exceed 4 c/d. Similar results were obtained in electrophysiological experiments when the visually evoked cortical potential (VECP) was recorded from anesthetized squirrels. A third experiment involved tests of the ability of ground squirrels to discriminate square-wave gratings of much higher luminance (340 cd/m2). The finest gratings which were discriminable at this luminance level did not exceed 3.9–4.3 c/d and, thus, we conclude that the maximal spatial resolution of the California ground squirrel is about 4 c/d (corresponding to a bar separation of 7.5′). In another behavioral experiment the abilities of ground squirrels to discriminate sinusoidally flickering lights (mean luminance = 3.4 cd/m2) was measured. The results show that ground squirrels are maximally sensitive to lights flickering at a rate of about 18 Hz, and that the highest rates that are still discriminable are slightly above 60 Hz.

Keywords

Contrast Sensitivity Ground Squirrel Luminance Level Visual Sensitivity High Luminance 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Abbreviations

c/d

cycles/degree

CFF

critical flicker frequency

VECP

visually evoked cortical potential

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Anderson, D.H., Jacobs, G.H.: Color vision and visual sensitivity in the California ground squirrel,Citellus beecheyi. Vision Res.12, 1995–2004 (1972)Google Scholar
  2. Berkley, M.A., Kitterle, R., Watkins, D.W.: Grating visibility as a function of orientation and retinal eccentricity. Vision Res.15, 239–244 (1975)Google Scholar
  3. Birch, D., Jacobs, G.H.: Spatial contrast sensitivity in albino and pigmented rats. Vision Res.19, 933–937 (1979)Google Scholar
  4. Blake, R., Cool, S.J., Crawford, M.L.J.: Visual resolution in the cat. Vision Res.14, 1211–1217 (1974)Google Scholar
  5. Campbell, F.W., Green, D.G.: Monocular versus binocular visual acuity. Nature (London)208, 191–192 (1965)Google Scholar
  6. Campbell, F.W., Kulikowski, J.J.: The visual evoked potential as a function of contrast of a grating pattern. J. Physiol.222, 345–356 (1972)Google Scholar
  7. Campbell, F.W., Maffei, L.: Electrophysiological evidence for the existence of orientation and size detectors in the human visual system. J. Physiol.207, 635–652 (1970)Google Scholar
  8. De Valois, R.L., Morgan, H.C., Snodderly, D.M.: Psychophysical studies of monkey vision. III. Spatial luminance contrast sensitivity of macaque and human observers. Vision Res.14, 75–81 (1974)Google Scholar
  9. Fisher, S.K., Jacobs, G.H., Anderson, D.H., Silverman, M.S.: Rods in the antelope ground squirrel. Vision Res.16, 875–877 (1976)Google Scholar
  10. Gur, M., Purple, R.L.: Retinal ganglion cell activity in the ground squirrel under halothane anesthesia. Vision Res.18, 1–14 (1978)Google Scholar
  11. Hughes, A.: The topography of vision in mammals of contrasting life style: Comparative optics and retinal organization. In: Handbook of sensory physiology, Vol. VII/5: The Visual system in vertebrates. Crescitelli, F. (ed.), pp. 615–756. Berlin, Heidelberg, New York: Springer 1977Google Scholar
  12. Jacobs, G.H.: Visual capacities of the owl monkey (Aotus trivirgatus). II. Spatial contrast sensitivity. Vision Res.17, 821–825 (1977)Google Scholar
  13. Jacobs, G.H.: Spectral sensitivity and colour vision in the ground-dwelling sciurids: Results from golden-mantled grounds squirrels and comparison for five species. Anim. Beh.26, 409–421 (1978)Google Scholar
  14. Jacobs, G.H., Birch, D.: Increment-threshold functions for different rodent species. Vision Res.15, 375–378 (1975)Google Scholar
  15. Jacobs, G.H., Fisher, S.K., Anderson, D.H., Silverman, M.S.: Scotopic and photopic vision in the California ground squirrel: Physiological and anatomical evidence. J. Comp. Neurol.165, 209–227 (1976)Google Scholar
  16. Kavanau, J.L., Rischer, C.E.: Optimum illumination for ground squirrel activity. Oecologia8, 391–399 (1972)Google Scholar
  17. Lindale, J.M.: The California ground squirrel. Berkeley: University of California Press 1946Google Scholar
  18. Merigan, W.H.: The contrast sensitivity of the squirrel monkey (Saimiri sciureus). Vision Res.16, 375–379 (1976)Google Scholar
  19. Michael, C.R.: Receptive fields of single optic nerve fibers in a mammal with an all cone retina. J. Neurophysiol.31, 249–282 (1968)Google Scholar
  20. Powers, M.K., Green, D.G.: Measurements of grating acuity, contrast sensitivity, refractive state and depth of focus of single retinal ganglion cells in the rat. Vision Res.18, 1533–1540 (1978)Google Scholar
  21. Reuter, J.H.: A comparison of flash evoked ERG's and ERG's evoked with sinusoidally modulated light stimuli in a number of rodents. Pflügers Arch.331, 95–102 (1972)Google Scholar
  22. Tansley, K.: Vision in Vertebrates. London: Chapman and Hall 1965Google Scholar
  23. Tong, L.: Contrast sensitive and color opponent optic tract fibers in the Mexican ground squirrel: Evidence for rod (502 λmax) input. Doctoral Dissertation, University of Michigan, Ann Arbor (1977)Google Scholar
  24. Tootell, R.B.H., Jacobs, G.H.: A simple surgical procedure for immobilization of rodent eyes. Vision Res.19, 1281–1282 (1979)Google Scholar
  25. Walls, G.L.: The vertebrate eye. Bloomfield Hills, Michigan: Cranbrook Institute of Science 1941Google Scholar
  26. West, R.W., Dowling, J.E.: Anatomical evidence for cone and rod-like receptors in the grey squirrel, ground squirrel, and prairie dog. J. Comp. Neurol.159, 439–460 (1975)Google Scholar
  27. Westheimer, G.: Visual acuity and spatial modulation thresholds. In: Handbook of sensory physiology, Vol. VII/4: Visual psychophysics. Jameson, D., Hurvich, L.M. (eds.), pp. 170–187. Berlin, Heidelberg, New York: Springer 1972Google Scholar
  28. Yolton, R.L., Yolton, D.P., Renz, J., Jacobs, G.H.: Preretinal absorbance in sciurid eyes. J. Mammal.55, 14–20 (1974)Google Scholar

Copyright information

© Springer-Verlag 1980

Authors and Affiliations

  • Gerald H. Jacobs
    • 1
  • Barbara Blakeslee
    • 1
  • Mark E. McCourt
    • 1
  • R. B. H. Tootell
    • 1
  1. 1.Department of PsychologyUniversity of CaliforniaSanta BarbaraUSA

Personalised recommendations