Visualization of neural activity in the rat visual cortex with intrinsic optical imaging

Abstract

The main objective of this study is to establish an intrinsic optical imaging method for visualizing functional architecture in the in vivo rodent visual cortex. For this purpose, we first determined the three optimal recording conditions for the imaging, viz., the depth of a focal plane, the wavelength of cortical illumination light, and the intensity of visual stimuli. Next, under the optimal recording conditions, we attempted to visualize the monocular (Oc1M) and binocular zones (Oc1B) in the primary visual cortex. The edges of differentially activated domains observed in the optical imaging corresponded to the boundary between Oc1M and Oc1B determined by a histochemical analysis. In addition, we successfully visualized a part of the extrastriate cortex (Oc2L). On the basis of these results, we concluded that we established the method for visualizing functional architecture in the in vivo rodent visual cortex using the intrinsic optical imaging technique. This method is expected to be useful for the assessment of the possible effects of genetic manipulation on the formation of functional architecture in the rodent visual cortex.