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A FUNCTIONAL ARCHITECTURE OF OPTIC FLOW IN THE INFERIOR PARIETAL CORTEX OF THE BEHAVING MONKEY INVESTIGATED WITH INTRINSIC OPTICAL IMAGING M. Raffi*; R.M. Siegel CMBN, Rutgers University, Newark, NJ, USA Area 7a neurons in the inferior parietal lobule are involved in the representation of visual self-motion and extra-personal space. An artificial dura exposed the most dorsal aspect of areas 7a and dorsal prelunate (DP). These areas were imaged at 605 nm for deoxyhemoglobin at the depth of 500m. Optical recordings were carried out on the right hemisphere of a male rhesus monkey. The animal was trained to fixate a 0.1 red dot and detect a change in the optic flow structure of 20 optic flow stimuli (radial expansion and contraction, rotation CW and CCW matched for speed) presented concentric to the red dot. This test was performed at two angles of gaze (up and down). Using a subtraction analysis, the optical response depended on the optic flow as well as the position of the eye in the orbit. There were patches that preferred expansion to contraction or vice versa; this relationship varied with eye position. An additional analysis revealed regions that were flow-general (FLO-G) as well as flow-particular (FLO-P) tuned (Siegel & Read, 1997). A three-way linear regression analysis using a spiral space for optic flow and a linear representation of eye position quantified the FLO-P and FLO-G responses. Different optic flows were represented in patches in dorsal areas 7a and DP with a small bias for contraction and CW motion across the cortex. The optic flow representation within DP is novel and is contiguous with 7a. The optic flow maps were modulated by the position of the eye in the orbit and were consistent over four months. Thus there is a fine scale topography for optic flow within more coarse gain field maps across 7a and DP in the inferior parietal lobule Supported by: NIH EY09223   Citation: M. Raffi, R.M. Siegel. A FUNCTIONAL ARCHITECTURE OF OPTIC FLOW IN THE INFERIOR PARIETAL CORTEX OF THE BEHAVING MONKEY INVESTIGATED WITH INTRINSIC OPTICAL IMAGING Program No. 56.9. 2002 Abstract Viewer/Itinerary Planner. Washington, DC: Society for Neuroscience, 2002. Online.