The long-range objective of this proposed research is to understand the neuronal mechanisms by which sensory information (both visual and acoustic) is used to direct saccadic eye movements. The research focuses on two major areas: the role of the cerebral cortex in the control of visually-guided eye movements and the interaction of visual and accoustic input onto cells in the deep and intermediate layers of the superior colliculus. The primary methodology consists of single-unit microelectrode recordings made in alert cats that have been trained to execute eye movements towards visual and accoustic targets. Eye movements will be monitored using the scleral seach coil technique, and cats will be trained using feedbck of eye position under computer control. The study of visually-guided eye movements will concentrate on three areas in the visual association cortices: the lateral suprasylvian, middle syprasylvian, and frontal eye fields. These areas all receive visual sensory input, but are hypothesized to be involved in different ways in the processing of this sensory input to motor commands. Differences in the response properties of cells in these three cortical regions to identical experimental conditions will help to elucidate the functional properties of these regions. In addition anatomical tracing studies will compare their efferent connections. Studies of the acoustic and visual interactions will examine cells in the deep layers of the superior colliculus. Since visual input is retinotopically coded and acoustic input is coded in a head-coordinate system, the responses of eye movement cells in the SC to these two inputs will provide useful information regarding the coding of saccadic eye movements. These studies are of interest to neurologists who are treating patients with deficits in eye movement control, and they may also prove useful for diagnosing lesions in the auditory pathway.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
5R01EY002606-09
Application #
3256927
Study Section
Visual Sciences B Study Section (VISB)
Project Start
1978-08-01
Project End
1988-02-29
Budget Start
1986-08-01
Budget End
1988-02-29
Support Year
9
Fiscal Year
1986
Total Cost
Indirect Cost
Name
University of Wisconsin Madison
Department
Type
Schools of Medicine
DUNS #
161202122
City
Madison
State
WI
Country
United States
Zip Code
53715
Yin, T C; Greenwood, M (1992) Visual response properties of neurons in the middle and lateral suprasylvian cortices of the behaving cat. Exp Brain Res 88:1-14
Yin, T C; Greenwood, M (1992) Visuomotor interactions in responses of neurons in the middle and lateral suprasylvian cortices of the behaving cat. Exp Brain Res 88:15-32
Yin, T C; Chan, J C (1990) Interaural time sensitivity in medial superior olive of cat. J Neurophysiol 64:465-88
Chang, A S; Frnka, J V; Chen, D N et al. (1989) Characterization of a genetically reconstituted high-affinity system for serotonin transport. Proc Natl Acad Sci U S A 86:9611-5
Yin, T C; Chan, J C; Carney, L H (1987) Effects of interaural time delays of noise stimuli on low-frequency cells in the cat's inferior colliculus. III. Evidence for cross-correlation. J Neurophysiol 58:562-83
Chan, J C; Yin, T C; Musicant, A D (1987) Effects of interaural time delays of noise stimuli on low-frequency cells in the cat's inferior colliculus. II. Responses to band-pass filtered noises. J Neurophysiol 58:543-61
Yin, T C; Chan, J C; Irvine, D R (1986) Effects of interaural time delays of noise stimuli on low-frequency cells in the cat's inferior colliculus. I. Responses to wideband noise. J Neurophysiol 55:280-300
Hirsch, J A; Chan, J C; Yin, T C (1985) Responses of neurons in the cat's superior colliculus to acoustic stimuli. I. Monaural and binaural response properties. J Neurophysiol 53:726-45
Yin, T C; Hirsch, J A; Chan, J C (1985) Responses of neurons in the cat's superior colliculus to acoustic stimuli. II. A model of interaural intensity sensitivity. J Neurophysiol 53:746-58