Implementation of optical coherence tomography (OCT) in visualization of functional structure of cat visual cortex

For the first time, OCT technique has been employed to obtain a depth-resolved functional dependent signal called differential OCT signal. Improvements in data acquisition and modifications of the system have been going on to improve the reliability of the results and also to incorporate the possibility of obtaining x-y and x-z scans so that a 3-D functional map at a lateral resolution of less than 50 urn and a depth resolution of less than 30 μm, much higher than the currently obtained ones could be obtained. Further, from the data obtained, we are also doing calculation to characterize origin of the OCT signal resulting from the scattering characteristics of the brain and degradation of the signal due to the reduction in coherence resulting from multiple scattering effects. Another aspect of current investigation is related to the temporal correlation of differential OCT signals as they may provide some insight into the type of ongoing activity in brain.