Abstract

The proposed research will investigate the anatomy, physiology and effects on visually guided behavior of inputs from the retina and nucleus isthmi on a central visual processing area, the optic tectum. The isthmotectal network of the leopard frog will be used as a model vertebrate system.
The specific aims are as follows: 1) To determine the retinal distribution of retinotectal ganglion cells after optic chiasm hemisections. Such hemisections spare visually guided prey catching and horseradish peroxidase histochemistry will be used to determine if there are regions of the tectum deafferented of retinal input. 2) To study possible behavioral and physiological changes after optic chiasm hemisection. Using both behavioral tests and single unit extracellular tectal recording, hemisected and matched controls will be compared. 3) To investigate changes in visually guided behavior after bilateral n. isthmi ablation. Animals will be tested to determine if visual deficits are global or primarily restricted to monocular visual fields. 4) To study the synaptic anatomy of horseradish peroxidase labeled isthmotectal and tectoisthmal axons. Electron microscopy will be used to determine the elements that are in synaptic contact with terminals of these axons. The long term objective of this study is to determine how visual information is processed in the central nervous system in order to further our understanding of vision.

  Funding Agency

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
5R01EY004366-08
Application #
3258742
Study Section
Visual Sciences B Study Section (VISB)
Project Start
1982-07-01
Project End
1993-11-30
Budget Start
1991-12-01
Budget End
1992-11-30
Support Year
8
Fiscal Year
1992
Total Cost
Indirect Cost

  Institution

Name
Temple University
Department
Type
Schools of Arts and Sciences
DUNS #
City
Philadelphia
State
PA
Country
United States
Zip Code
19122

  Publications

King Jr, J G; Lettvin, J Y; Gruberg, E D (1999) Selective, unilateral, reversible loss of behavioral responses to looming stimuli after injection of tetrodotoxin of cadmium chloride into the frog optic nerve. Brain Res 841:20-6
Dudkin, E A; Gruberg, E R (1999) Relative number of cells projecting from contralateral and ipsilateral nucleus isthmi to loci in the optic tectum is dependent on visuotopic location: horseradish peroxidase study in the leopard frog. J Comp Neurol 414:212-6
Stull, A K; Gruberg, E R (1998) Prey selection in the leopard frog: choosing in biased and unbiased situations. Brain Behav Evol 52:37-45
Dudkin, E A; Myers, P Z; Ramirez-Latorre, J A et al. (1998) Calcium signals monitored from leopard frog optic tectum after the optic nerve has been selectively loaded with calcium sensitive dye. Neurosci Lett 258:124-6
Weber, B C; Waldeck, R F; Gruberg, E R (1996) Seeing beyond the midline: the role of the contralateral isthmotectal projection in the leopard frog. Vis Neurosci 13:467-76
Waldeck, R F; Gruberg, E R (1995) Regrowth of optic fibers and behavioral recovery after optic chiasm transection. Exp Neurol 132:229-38
Waldeck, R F; Gruberg, E R (1995) Studies on the optic chiasm of the leopard frog. I. Selective loss of visually elicited avoidance behavior after optic chiasm hemisection. Brain Behav Evol 46:84-94
Tsai, J; Waldeck, R F; Gruberg, E R (1995) Studies on the optic chiasm of the leopard frog. II. Organization of retinotectal fibers in the optic chiasm. Brain Behav Evol 46:95-107
Gruberg, E R; Hughes, T E; Karten, H J (1994) Synaptic interrelationships between the optic tectum and the ipsilateral nucleus isthmi in Rana pipiens. J Comp Neurol 339:353-64
Gruberg, E R; Wallace, M T; Caine, H S et al. (1991) Behavioral and physiological consequences of unilateral ablation of the nucleus isthmi in the leopard frog. Brain Behav Evol 37:92-103

Showing the most recent 10 out of 15 publications