Summary
The California ground squirrel (Spermophilus beecheyi) has two classes of cone photopigments (λmax = 440 and 525 nm). Under photopic conditions about 30% of all optic nerve fibers receive inputs from both cone classes, the remainder are driven solely by the 525 nm cone. Recordings were made from optic nerves in young ground squirrels to trace the development of their spectral responsivity. Animals were reared from birth in one of three photic environments: white light, darkness, or red light. In the youngest ground squirrels examined (ca. 50 days old) many units receiving inputs from the 525 nm cone were found, but the proportion of units receiving inputs from both cone classes was significantly lower than that of adults. From these initial low levels the proportion of such units increases gradually. Adult proportions were achieved at varying rates which depended on the photic environment in which the animal was reared: animals reared in white light achieved the adult standard earliest, those reared in darkness somewhat later, and the animals reared in red light required much longer to achieve the adult organization. We conclude that: (a) the neural substrates for normal color vision in this species develop to some extent postnatally, and (b) the normal sequence of development can be significantly extended by spectral environments which provide a highly biased stimulation of the two cone mechanisms.
Similar content being viewed by others
References
Anderson DH, Jacobs GH (1972) Color vision and visual sensitivity in the California ground squirrel, Citellus beecheyi. Vision Res 12: 1995–2004
Aslin RN, Alberts JR, Petersen MR (1981) Development of perception. The visual system, vol 2. Academic Press, New York
Birch D, Jacobs GH (1977) Effects of constant illumination on vision in the albino rat. Physiol Behav 19: 255–259
Boothe RG, Teller DY, Sackett G (1975) Trichromacy in normally reared and light deprived infant monkeys (Macaco nemestrina). Vision Res 15: 1187–1191
Chow KL (1955) Failure to demonstrate changes in the visual system of monkeys kept in darkness or in color lights. J Comp Neurol 102: 597–606
Freeman RD (1979) Developmental neurobiology of vision. Plenum Press, New York
Fitch HS (1948) Ecology of the California ground squirrel on grazing lands. Am Midl Nat 39: 513–596
Gur M, Purple RL (1978) Retinal ganglion cell activity in the ground squirrel under halothane anesthesia. Vision Res 18: 1–14
Jacobs GH (1978) Spectral sensitivity and colour vision in the ground-dwelling sciurids: Results from golden-mantled ground squirrels and comparisons for five species. Anim Behav 26: 409–421
Jacobs GH, Birch D (1975) Increment-threshold functions for different rodent species. Vision Res 15: 375–378
Jacobs GH, Blakeslee B, Tootell RBH (1981) Color discrimination tests on fibers in the ground squirrel optic nerve. J Neurophysiol 45: 903–914
Jacobs GH, Fisher SK, Anderson DH, Silverman MS (1976) Scotopic and photopic vision in the California ground squirrel: Physiological and anatomical evidence. J Comp Neurol 165: 209–228
Jacobs GH, Tootell RBH (1981) Spectral response properties of optic nerve fibers in the ground squirrel. J Neurophysiol 45: 891–902
LeGros Clark WE (1940) Anatomical basis of colour vision. Nature 146: 558–559
Linsdale JM (1946) The California ground squirrel. Univ. of Calif. Press, Berkeley
McCourt ME (1982) Spatial and directional filter characteristics of single units in the optic nerve of the California ground squirrel (Spermophilus beecheyi). Doctoral Disseration Univ. of California, Santa Barbara
Michael CR (1968) Receptive fields of single optic nerve units in a mammal with an all-cone retina. J Neurophysiol 31: 249–282
Moore CL, Kalil R, Richards W (1976) Development of myelination in optic tract of cat. J Comp Neurol 165: 125–136
Movshon JA, Van Sluyters RC (1981) Visual neural development. Annu Rev Psychol 32: 477–522
Pengelley ET (1966) Differential developmental patterns and their adaptive values in various species of the genus Citellus. Growth 30: 137–142
Pulos E, Teller DY, Buck SL (1980) Infant color vision: A search for short-wavelength-sensitive mechanisms by means of chromatic adaptation. Vision Res 20: 485–493
Tong L (1977) Contrast sensitive and color opponent optic tract fibers in the Mexican ground squirrel: Evidence for a rod (502 λmax) input. Doctoral Dissertation, Univ. of Michigan
Tootell RBH, Jacobs GH (1979) A simple surgical procedure for immobilization of rodent eyes. Vision Res 19: 1281–1282
Walls GL (1953) The lateral geniculate nucleus and visual histophysiology. Univ Calif Publ Physiol 9: 1–100
Weidman TA, Kuwubara T (1968) Postnatal development of the rat retina. Arch Ophthalmol 79: 470–484
Author information
Authors and Affiliations
Additional information
Supported by a grant from the National Eye Institute (EY-00105)
Rights and permissions
About this article
Cite this article
McCourt, M.E., Jacobs, G.H. Effects of photic environment on the development of spectral response properties of optic nerve fibers in the ground squirrel. Exp Brain Res 49, 443–452 (1983). https://doi.org/10.1007/BF00238785
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00238785