The ultimate goals of this proposal are to identify organizational principles of information flow and integration in sensorimotor systems of the brain. The model perhaps best suited for this is the oculomotor system, where visual percepts are integrated with high order behavioral processes for the production of highly precise saccadic eye movements. By studying this """"""""simple"""""""" behavior, we hope to understand some of the general mechanisms by which the brain produces all behavior. Studying the brain in awake, behaving subjects allows a degree of insight into high order brain functions that is not possible in other experimental models. Globally, these studies help us to understand the biological solutions for the problem of information flow in the brain and the transformation of visual signals for movement control. This is important not only for understanding the biology of eye movements in humans, but to the problem of movement control and behavior in general. We propose to study the activity of individual neurons in the posterior parietal cortex and the superior colliculus during simple visual and eye movement behavior. We have shown that parietal neurons are part of the process for translating the spatial position of visual stimuli into the commands for moving the eyes. We will identify individual neurons that project from parietal cortex to other oculomotor centers (the superior colliculus and the frontal eye fields). By studying these neurons we can determine the transfer of information from one brain area to the next. We will use both empirical and modeling techniques. We will construct models of the transformations determined from the biological experiments. We will then use the models to make new predictions that can be tested in the lab.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
2R01EY008217-06A2
Application #
2019729
Study Section
Visual Sciences B Study Section (VISB)
Project Start
1996-12-01
Project End
1999-11-30
Budget Start
1996-12-01
Budget End
1997-11-30
Support Year
6
Fiscal Year
1997
Total Cost
Indirect Cost
Name
State University New York Stony Brook
Department
Other Basic Sciences
Type
Schools of Arts and Sciences
DUNS #
804878247
City
Stony Brook
State
NY
Country
United States
Zip Code
11794
Noto, Christopher T; Gnadt, James W (2009) Saccade trajectories evoked by sequential and colliding stimulation of the monkey superior colliculus. Brain Res 1295:99-118
Paul, Kush; Gnadt, James W (2006) Activity of omnipause neurons during ""staircase saccades"" elicited by persistent microstimulation of the superior colliculus. Vision Res 46:3430-42
Carasig, Dana; Paul, Kush; Fucito, Michele et al. (2006) Irrepressible saccades from a tectal lesion in a Rhesus monkey. Vision Res 46:1161-9
Ramcharan, E J; Gnadt, J W; Sherman, S M (2005) Higher-order thalamic relays burst more than first-order relays. Proc Natl Acad Sci U S A 102:12236-41
Gnadt, James W; Echols, Stanley D; Yildirim, Abidin et al. (2003) Spectral cancellation of microstimulation artifact for simultaneous neural recording in situ. IEEE Trans Biomed Eng 50:1129-35
Paul, Kush; Gnadt, James W (2003) Reliable real-time spike discrimination during microstimulation. J Neurosci Methods 128:191-5
Gnadt, J W; Jackson, M E; Litvak, O (2001) Analysis of the frequency response of the saccadic circuit: system behavior. J Neurophysiol 86:724-40
Jackson, M E; Litvak, O; Gnadt, J W (2001) Analysis of the frequency response of the saccadic circuit: numerical simulations. Neural Netw 14:1357-76
Jackson, M E; Gnadt, J W (1999) Numerical simulation of nonlinear feedback model of saccade generation circuit implemented in the LabView graphical programming language. J Neurosci Methods 87:137-45
Gnadt, J W; Beyer, J (1998) Eye movements in depth: What does the monkey's parietal cortex tell the superior colliculus? Neuroreport 9:233-8

Showing the most recent 10 out of 15 publications