Human neurophysiological mechanisms of contextual modulation in primary visual cortex
Research Specialist, Otolaryngology-HNS, 3M
Undergraduate Institution and Major/Degree:
Arizona State University, BSE Bioengineering, 2005
My research focuses on high-resolution functional magnetic resonance imaging (fMRI) and the role of local neural inhibition in early human visual areas. Inhibition is a fundamental aspect of visual processing, playing a role in neural computations both between and within cortical areas of the brain. Understanding local inhibition in vision is important for its role in viewing and parsing natural scenes, such as separating figure from background. My thesis work thus far involves developing fMRI methodology to precisely define specific spatial locations in human primary visual cortex (V1) over time and investigating the blood oxygenation level dependent (BOLD) response to local neural inhibition via contextual modulation. Later avenues of research will include using natural textures to further study the neurophysiological mechanisms of inhibition and exploring the efficacy of video games for psychophysical experiments and perceptual learning.
- David Redish
- Matthew Chafee
- Dan Kersten
- Cheryl Olman
Courses Taken Beyond the Core Courses:
- BMEn 5401 - Advanced Functional Biomedical Imaging
- PSY 5036W - Computational Vision
- PSY 5960 – Signal Detection Theory
- PSY 8036 – Feedfoward/Feedback Interactions in Visual Processing
- PSY 8960 – Biological Basis of BOLD Seminar
- PSY 8993 – Hands-On fMRI Training
- Brain ’07 biennial meeting – May 2007
- Vision Sciences Society annual meeting – May 2007
- Society for Neuroscience 2004, 2005, 2007
- Gordon Research Conference: Brain energy metabolism and blood flow - August 2006
- Schumacher JF, Quinn CF, Olman CA. An exploration of the spatial scale over which orientation-dependent surround effects affect contour detection. J Vis. 2011;11(8):12.
- Schumacher JF, Thompson, SK, Olman CA. Contrast response functions for single Gabor patches: GE BOLD over-represents low-contrast patches but SE BOLD does not. Front Syst Neurosci. 2011 Mar 24;5:19.
- Schumacher JF, Olman CA. High-resolution BOLD fMRI measurements of local orientation-dependent contextual modulation show a mismatch between predicted V1 output and local BOLD response. Vision Res. 2010;50(13):1214-24.
- Olman CA, Van de Moortele P-F, Schumacher JF, Guy JR, Uĝurbil K, Yacoub E. Retinotopic mapping with spin echo BOLD at 7T. Magn Reson Imaging. 2010;28(9):1258-69.
- Schumacher JF, Quinn CF, Olman CA. Parameter exploration of contextually modulated collinear Gabor patches. Journal of Vision, 2010;10(7):1158.
- Olman C, Schumacher J, Thompson S. Non-linear BOLD response to low-contrast Gabor elements. Journal of Vision, 2010;10(7), 916.
- Olman C, Boyaci H, Schumacher J, Fang F, Doerschner K. Receptive field properties of V1 neurons coding for luminance histogram skew. Journal of Vision, 2009;9(8): 774, 774a.
- Olman CA, Moeller S, Schumacher JF, Thompson SK, Auerbach EJ, Ugurbil K, Yacoub E. Investigating the whole brain with 1.5mm isotropic resolution and1.5s TRs using highly accelerated high-field fMRI. International Society of Magnetic Resonance in Medicine, 17th Scientific Meeting and Exhibition, Honolulu, Hawaii, 2009.
- Thompson S, Olman CA. Schumacher JF, Kersten D, Engel SA. Stronger functional MRIresponses being earlier in time. Society for Neuroscience Annual Meeting, Washington DC, 2008.
- Schumacher JF, Olman CA. 7T Spin Echo Sequences Provide Improved Spatial Accuracy of BOLD fMRI Experiments. Journal of Vision 2008;8(6): 804, 804a.
- Schumacher JF, Olman CA. BOLD response to local neural inhibition. Journal of Vision 2007;7(9): 80a.
- Schumacher, J.F. & Olman, C.A. (2007). “BOLD Response to Local Neural Inhibition” [Abstract]. Journal of Vision 7(9): 80a.
- Schumacher J.F. , Olman C.A. “Contextual Modulation of the High-Resolution 3T GE BOLD fMRI Response” (poster presentation). 23 rd International Symposium on Cerebral Blood Flow, Metabolism, and Function; Osaka, Japan (May 20-24, 2007).
- Schumacher J.F. , Halloway-Nahum A, Olman C.A. “BOLD Response to Local Neural Inhibition” (poster presentation). Gordon Research Conference: Brain Energy Metabolism & Blood Flow; Oxford, England (August 20-25, 2006).
Awards and Honors:
- NIH-NPCS Graduate Training Fellowship: 2005-2007
- Society for Neuroscience
- Vision Sciences Society
- Tau Beta Pi
- Air Force Brat (i.e. everywhere)