Condon Lau1,2, Jevin W. Zhang1,2, Matthew M. Cheung1,2, Kyle Xing1,2, Iris Y. Zhou1,2, Kevin C. Chan1,2, Ed X. Wu1,2
1Laboratory of Biomedical Imaging & Signal Processing, the University of Hong Kong, Hong Kong, Hong Kong SAR, China, People's Republic of; 2Department of Electrical & Electronic Engineering, the University of Hong Kong, Hong Kong, Hong Kong SAR, China, People's Republic of
In rats, the superior colliculus (SC) is the main destination for retinal ganglion cells and is an important subcortical structure for vision. Many of its neurons are highly sensitive to moving objects. BOLD fMRI is used to measure the SCs hemodynamic response, in Sprague-Dawley rats, to a visual stimulus moving at five speeds between 7 and 164/s. Significant responses are observed at all speeds tested. The maximum response amplitude occurred at 41 and 82/s and the minimum at 164/s. The number of responsive voxels was lowest at 164/s. These findings appear to be in agreement with electrical recording studies.