Hostname: page-component-8448b6f56d-jr42d Total loading time: 0 Render date: 2024-04-24T14:42:24.769Z Has data issue: false hasContentIssue false
  • English
  • Français

The pupillary response to light in the turtle

Published online by Cambridge University Press:  02 June 2009

A. M. Granda ,
J. R. Dearworth Jr ,
C. A. Kittila  and
W. D. Boyd
A. M. Granda
Affiliation:
University of Delaware, Newark
J. R. Dearworth Jr
Affiliation:
University of Delaware, Newark
C. A. Kittila
Affiliation:
Sensory Sciences Center, University of Texas, Houston
W. D. Boyd
Affiliation:
Jefferson Medical School, Philadelphia
Get access Rights & Permissions [Opens in a new window]

Abstract

When intense adapting lights are turned off, the pupil of the turtle, Pseudemys scripta elegans, enlarges. The recovery functions for pupillary dilation have different time constants that are defined by red- and green-sensitive cones and rods as they are affected by prior light adaptation and time in the dark. Pupillary area related to dilation responds over at least a three- to four-fold range. Following white-light adaptation, the course of pupil dilation in the dark shows a three-legged curve of differing time constants. With spectral-light adaptations, the contributions of separate classes of photoreceptors can be isolated. Red- and green-sensitive cones contribute shorter time constants of 3.31 and 3.65 min to prior white-light adaptation—4.81 and 4.18 min to prior spectral-light adaptations. Rods contribute a much longer time constant of 6.69 min to prior white-light adaptation—7.60 min to prior spectral-light adaptation. The ratios are in keeping with the flash sensitivities of photoreceptors in this same animal, as well as with psychophysical visual threshold mechanisms of color sensitivity.

Keywords

PupillographyTurtlePhotoreceptorsDark and light adaptationPsychophysical visual threshold mechanismsElectrophysiological flash sensitivities
Type
Research Articles
Information
Visual Neuroscience , Volume 12 , Issue 6 , November 1995 , pp. 1127 - 1133
Copyright
Copyright © Cambridge University Press 1995

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Alpern, M., Kitai, S. & Isaacson, J.D. (1959). The dark-adaptation process of the pupillomotor photoreceptors. American Journal of Ophthalmology 48, 583–593.CrossRefGoogle Scholar
Baylor, D.A. & Hodgkin, A.L. (1973). Detection and resolution of visual stimuli by turtle photoreceptors. Journal of Physiology (London) 234, 163–198.CrossRefGoogle ScholarPubMed
Baylor, D.A. & Hodgkin, A.L. (1974). Changes in time scale and sensitivity in turtle photoreceptors. Journal of Physiology (London) 242, 729–758.CrossRefGoogle ScholarPubMed
Baylor, D.A. & Fettiplace, R. (1975). Light path and photon capture in turtle photoreceptors. Journal of Physiology (London) 248, 433–464.CrossRefGoogle ScholarPubMed
Brown, K.T. (1969). A linear area centralis extending across the turtle retina and stabilized to the horizon by non-visual cues. Vision Research 9, 1053–1062.CrossRefGoogle Scholar
Copenhagen, D.R. & Owen, W.G. (1976). Functional characteristics of lateral interactions between rods in the retina of the snapping turtle. Journal of Physiology (London) 259, 251–282.CrossRefGoogle ScholarPubMed
Defares, J.G. & Sneddon, I.N. (1964). An Introduction to the Mathematics of Medicine and Biology, Chicago, Illinois: Year Book Medical Publications, Inc. 663 pp.Google Scholar
Detwiler, P.B., Hodgkin, A.L. & McNaughton, P.A. (1980). Temporal and spatial characteristics of the voltage response of the rods in the retina of the snapping turtle. Journal of Physiology (London) 300, 213–250.CrossRefGoogle ScholarPubMed
Dvorak, C.A., Granda, A.M. & Maxwell, J.H. (1980). Photoreceptor signals at visual threshold. Nature 283, 860–861.CrossRefGoogle ScholarPubMed
Granda, A.M. & Sisson, D.F. (1989). Psychophysically derived visual mechanisms in turtle. I –Spectral properties. Vision Research 29, 93–105.CrossRefGoogle ScholarPubMed
Loewenfeld, I.E. (1993). The Pupil–Anatomy, Physiology, and Clinical Applications. Vol. 1 (1590 pp.); and Bibliography and Index. Vol. II (633 pp.) Detroit, Michigan: Wayne State University Press.Google Scholar
Lowenstein, O. & Loewenfeld, I.E. (1959). Scotopic and photopic thresholds of the pupillary light reflex in normal man. American Journal of Ophthalmology 48, 87–98.CrossRefGoogle ScholarPubMed
Northmore, D.P.M. & Granda, A.M. (1991a). Refractive state, contrast sensitivity, and resolution in the freshwater turtle, Pseudemys scripta elegans, determined by tectal visual-evoked potentials. Visual Neuroscience 7, 619–625.CrossRefGoogle ScholarPubMed
Northmore, D.P.M. & Granda, A.M. (1991b). Ocular dimensions and schematic eyes of freshwater and sea turtles. Visual Neuroscience 7, 627–635.CrossRefGoogle ScholarPubMed
Sisson, D.F. & Granda, A.M. (1989). Psychophysically derived visual mechanisms in turtle. II–Spatial properties. Vision Research 29, 107–114.CrossRefGoogle ScholarPubMed
Stark, L. (1962). Biological rhythms, noise, and asymmetry in the pupil-retinal control system. Annals of the New York Academy of Medicine 98, 1096–1108.CrossRefGoogle ScholarPubMed
Van Der Tweel, L.H. (1956). De Reactie van de Pupil bij de Mens op Verandering in de Belichting. Dissertation, Amsterdam. Amsterdam: Studentendruckerij “Poortypers,” 59 pp. Translated in The Light Reflex of the Normal Pupil of Man, Van Der Tweel, L.H. & van der Gon, J.J. (1959). Acta Physiologica Neerlander 8, 52–58.Google Scholar
Walls, G.L. (1942). The Vertebrate Eye and Its Adaptive Radiation. New York: Hafner Publishing Company, (1967 facsimile edition), 785 pp.Google Scholar