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Color Mechanisms: A Progress Report

Hosted By: Color Technical Group

27 June 2023 11:00 - 12:00

Eastern Time (US & Canada) (UTC - 05:00)

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A fundamental issue in color vision is understanding the ways in which photoreceptor signals are combined in order to detect and discriminate colors. The neural circuits in which these signals interact are called color channels or color mechanisms. It is not clear how many such mechanisms are required to account for even the most basic visual tasks, and there is no generally accepted computable model of these mechanisms.

In this webinar hosted by the Color Technical Group, Rhea Eskew will review evidence for one fully-computable model of L and M cone signals, based upon evidence from detection under noise masking conditions, and relate that model to data on asymmetric color matching and forced-choice chromatic discrimination. Progress towards expanding the model to the full three-dimensional color space (to include S cone signals) will also be described.

What You Will Learn:
• What a color channel or mechanism is
• How cone signals are combined into postreceptoral mechanisms
• How many color mechanisms there are

Who Should Attend:
• Color scientists and engineers who wish to better understand basic color vision
• Neuroscientists who want to learn about functional models of color discrimination

About the Presenter: Rhea Eskew from Northeastern University 

Rhea Eskew did his graduate work at the Georgia Institute of Technology, applying nonlinear systems analysis techniques to human spatial vision.  After obtaining his Ph.D., he became a postdoctoral fellow at the Center for Human Information Processing at the University of California at San Diego, where he worked with Robert M. Boynton on color discrimination.  He next spent four years as a Research Associate in Biomedical Physics at Harvard University, working on chromatic detection in the lab of Charles Stromeyer and Richard Kronauer. In 1990 he moved to Northeastern University, where he is now Professor of Psychology. Dr. Eskew’s research is primarily focused on color vision. An experimentalist, he collects detection and discrimination data and uses it to test quantitative models of early and mid-level vision.  He is a Fellow of Optica. His research has been supported by the Air Force Office of Scientific Research, the National Eye Institute, and more.

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