Optical imaging of intrinsic signals (OIS) has improved our understanding of the functional organization of the cerebral cortex. However, the technique places time constraints on experiments due to the averaging needed to overcome cardiovascular noise. A novel OIS method, using continuous image acquisition of a periodically presented stimulus, followed by a Fourier decomposition, promises to reduce experiment time while separating the stimulated response from the cardiovascular noise. Discrete, periodic finger stimulation and Fourier OIS were used to generate a functional map of finger somatotopy in squirrel monkey SI cortex. Phase delay correction was successfully performed through both stimulus reversal/subtraction and subtraction of a single, discrete stimulus. Magnitude borders between digits were described, and a harmonic analysis showed that they are caused by overlapping response from the adjacent finger representation. Digit selectivity analysis demonstrated a selectivity gradient within digit representations in both cortical areas 3b and 1. Significance maps were generated by calculating the signal-to-noise ratio (SNR) for each pixel. SNR maps required more stimulation repetitions than magnitude maps, but demonstrated higher sensitivity for regions with low activity and less overall blood vessel artifact. Finally, a comparison to episodic OIS and electrophysiological receptive field mapping showed that Fourier OIS maps are comparable to those standards.
| Identifer | oai:union.ndltd.org:VANDERBILT/oai:VANDERBILTETD:etd-03252014-112411 |
| Date | 27 March 2014 |
| Creators | Winberry, Jeremy Edward |
| Contributors | Mark Wallace, Ph.D., Anna W. Roe, Ph.D., Troy Hackett, Ph.D., Peter Konrad, M.D., Ph.D. |
| Publisher | VANDERBILT |
| Source Sets | Vanderbilt University Theses |
| Language | English |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://etd.library.vanderbilt.edu/available/etd-03252014-112411/ |
| Rights | unrestricted, I hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to Vanderbilt University or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report. |
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