University of California, Los Angeles, CA

Home Page
About SAEN
Articles and Reports
Contact Us
Events and Campaigns
Fact Sheets
Financial Information
How You Can Help
Make a Donation, Please!
Media Coverage
Picture Archive
Press Releases
Resources and Links
Grass Roots Org. List

Stop Animal Exploitation NOW!
S. A. E. N.
"Exposing the truth to wipe out animal experimentation"

Government Grants Promoting Cruelty to Animals

University of California, Los Angeles, CA

DARIO L. RINGACH - Primate Testing - 2006

Grant Number: 5R01EY012816-07
Project Title: Quantitative Studies of Cortical Visual Processing
PI Information: ASSOCIATE PROFESSOR DARIO L. RINGACH, [email protected] 

Abstract: DESCRIPTION (provided by applicant):
The objective of this proposal is to understand the nature of ongoing cortical activity, what it represents, and how it interacts with external stimuli to generate a "real-time" response in primary visual cortex.

We propose to use micro-machined electrode arrays to simultaneously record local-field potentials and single-unit activity, in combination with novel methods of mathematical analysis, to perform the following studies:

(a) to measure and mathematically model the dynamics of cortical activity, in spontaneous and stimulus evoked regimes. We will test the hypothesis that cortical activity is structured and can be represented in a low-dimensional space. Novel mathematical models will be developed that predict population responses on a trial-to-trial basis.

(b) To determine how populations of neurons represent distributions of physical attributes (such as orientation) within a local area of the visual field. We will test the hypothesis that dynamic switching among cortical states is involved in the representation of orientation distributions.

(c) To measure, and mathematically model, the response of the cortical population to electrical stimulation through individual or groups of electrodes. The resulting model will be used in the design of a real-time controller of cortical activity.

Given a pattern of cortical activity as a "target", we will test our ability to bring the population response into the target pattern via electrical stimulation. We will develop safe stimulation protocols by constraining the spatio-temporal pattern of electrical stimulation across the electrode array.

The significance of the proposed work is its contribution to understanding the cortex as a "real-time" processing device. The findings will reveal how ongoing activity is structured, and how it combines with incoming visual stimulation to generate a response on a trial-by-trial basis.

We will advance our basic knowledge of cortical function by investigating how neural populations represent distributions of physical attributes within a local region of the visual field.

Finally, the techniques and methods developed here will be instrumental in the design of cortical prostheses for the restoration of sensory function, which require the activity of a large population of neurons to be controlled using a limited number of stimulating electrodes.

Thesaurus Terms:
brain electrical activity, neural information processing, neural transmission, visual cortex, visual stimulus electrostimulus, evoked potential, mathematical model, method development, model design /development, neuroanatomy, time resolved data, visual field Macaca fascicularis, computer data analysis, electrophysiology, microelectrode

Office of Research Administration
Fiscal Year: 2006
Project Start: 01-FEB-2000
Project End: 31-JAN-2010

Please email:  DARIO L. RINGACH, [email protected] to protest the inhumane use of animals in this experiment. We would also love to know about your efforts with this cause: [email protected]

Return to Grants
Return to University of California, Los Angeles, CA
Return to Facility Reports and Information
Return to Resources and Links

Rats, mice, birds, amphibians and other animals have been excluded from coverage by the Animal Welfare Act. Therefore research facility reports do not include these animals. As a result of this situation, a blank report, or one with few animals listed, does not mean that a facility has not performed experiments on non-reportable animals. A blank form does mean that the facility in question has not used covered animals (primates, dogs, cats, rabbits, guinea pigs, hamsters, pigs, sheep, goats, etc.). Rats and mice alone are believed to comprise over 90% of the animals used in experimentation. Therefore the majority of animals used at research facilities are not even counted.

We welcome your comments and questions

This site is hosted and maintained by:
The Mary T. and Frank L. Hoffman Family Foundation
Thank you for visiting
Since date.gif (991 bytes)