Sunwoo Kwon

Vision Center Laboratory
Center for Neurobiology of Vision
Salk Institute for Biological Studies
10010 North Torrey Pines Road
La Jolla, CA 92037, USA

858.453.4100 ext 1215 | office
kwsunwoo (at) salk.edu


Overview

I am a graduate student/prospective vision scientist interested in image processing, perception, and sensation. My focus is on the center-surround interactions in regards with the process called perceptual organization of human perception.

  • Perceptual organization is the process that structures visual input into logical, comprehensible information used by the visual system.
  • In center-surround interactions, the perceived contrast of a central stimulus can be either inhibited (surround suppression) or amplified (surround facilitation) as a result of the presence of various types surround stimuli. Therefore, human contrast sensitivity may be decreased (suppression) or increased (facilitation).
  • The information, whether static or in motion, that enters the visual system must be categorized, systemized, grouped, segmented, and organized or else the brain will not be able to process such information. Such mechanisms may include contour integration, figure-ground segregation, edge detection, 'pop-out' effect, curvature detection, and detection of illusory contours.
  • Importantly, studies of spatial contextual modulation ("center-surround interactions") produced numerous contradictory results in narrow samples of stimuli. Through my psychophysical experiments, which mostly consist of larger parameter space, I hope to find invariants of center-surround interactions in the visual system.

For past few years, under the mentorship of Dr. Thomas Albright and Dr. Sergei Gepshtein, I have studied the center-surround interactions underlying these processes, in particular how visual systems organize information for the perception of static stimulus under various parameters. For experiments, I use psychophsyical methods in order to understand how human contrast sensitivity/contrast sensitivity function (CSF) changes, whether facilitation or suppression, under different stimulus settings (VSS2014 Abstract).

Projects

  • Currently working on writing a manuscript with latest findings with Dr. Albright, Dr. Gepshtein, and Dr. Saveliev for publication.
  • Effects of phase and counter-phase via inhibition-stabilized networks.
  • Effects of phase and counter-phase on the orientation discrimination of static center-surround grating columns in the foveal vision vs. peripheral vision.
  • Effects of various phases shifts on the global collinear orientation of center-surround gratings.
  • Invariants of center-surround interactions: effects of lateral collinear facilitation across surround contrast and surround spatial frequency (SF) on central grating.
  • Effects of surround annulus grating on the direction discrimination of dynamic central grating.
  • Effects of varying distances of center-surround stimuli on the collinear lateral interactions.

Education & CV

  • Salk Institute: 2012-2015
  • M.S. in Biology at University of California San Diego (UCSD): 2012-2015
  • B.S. in Biochemistry & Cell Biology at University of California San Diego (UCSD): 2007, 2010-2012

Photographs