The fundamental issue underlying this proposal is the mechanism responsible for associative learning in mammals. Two of the most successful model systems today involve adaptions of the vestibulo-ocular reflex (VOR) and classical conditioning of the nictitating membrane response (NMR). This proposal seeks to significantly extend our understanding of associative learning mechanisms by an in-depth computational and neurophysiological analysis of VOR and its adaptation in the cat combined with an effort to bridge the conceptual gap between this model system and NMR conditioning. Three key questions will be explored: 1. Can a computational model of neural function constrained by known physiology, account for the currently described behavior as well as serve as a heuristic tool in directing further experimentation? This defines a bottom-up approach which has not been utilized on this scale previously in analyzing a specific response system. Our prior modeling work in this project. These predictions include identification of: a) likely anatomical site for learning to take place and b) a physiological substrate for the """"""""teacher"""""""" signal in a supervised learning algorithm used to represent reflex plasticity. 2. What is the precise nature of the changes which take place at the single neuron level which ar responsible for the development of motor learning? A two-prong approach to help answer this critical questions is proposed. First, an in-depth characterization of the changes in the spatial characteristic of neurons crucial to expression of the VOR will be conducted. Second, u sing stimulation and lesion techniques the nature of the training signal responsible for guiding plasticity in the reflex will be explore. 3. Can mechanisms accounting for both VOR adaption and classical conditioning of the NMR be unified under a single learning scheme? Different ways in which to map the VOR adaption paradigm to a classical conditioning paradigm will be explored. A clear demonstration of VOR adaptation development under conditions defined by classical conditioning would lead the way to unifying these two significant bodies of investigation into associative learning mechanisms. The benefits of a clear understanding of how the brain express associative learning are enormous form a societal viewpoint; from better recovery of function in stroke patients, to improvements in the behavioral capabilities of the mentally retarded to, potentially, an improvement in the ability of our society, as a whole, to increase its intellectual capacities.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
First Independent Research Support & Transition (FIRST) Awards (R29)
Project #
5R29NS031805-02
Application #
2269743
Study Section
Biopsychology Study Section (BPO)
Project Start
1994-06-01
Project End
1999-05-31
Budget Start
1995-06-01
Budget End
1996-05-31
Support Year
2
Fiscal Year
1995
Total Cost
Indirect Cost
Name
Northwestern University at Chicago
Department
Physiology
Type
Schools of Dentistry
DUNS #
005436803
City
Chicago
State
IL
Country
United States
Zip Code
60611
Quinn, K J; Rude, S A; Brettler, S C et al. (1998) Alterations in rat horizontal vestibulo-ocular reflex phase as a function of orientation in gravity. J Gravit Physiol 5:41-9
Quinn, K J; Baker, J F (1998) Processing of spatial information by floccular and non-floccular target neurons in the alert cat. Brain Res 780:143-9
Quinn, K J; Rude, S A; Brettler, S C et al. (1998) Chronic recording of the vestibulo-ocular reflex in the restrained rat using a permanently implanted scleral search coil. J Neurosci Methods 80:201-8
Quinn, K J (1998) Classical conditioning using vestibular reflexes. J Vestib Res 8:117-33
Quinn, K J; Helminski, J O; Didier, A J et al. (1996) Changes in sensitivity of vestibular nucleus neurons induced by cross-axis adaptation of the vestibulo-ocular reflex in the cat. Brain Res 718:176-80
Peterson, B W; Kinney, G A; Quinn, K J et al. (1996) Potential mechanisms of plastic adaptive changes in the vestibulo-ocular reflex. Ann N Y Acad Sci 781:499-512