Spatially-spectrally-resolved reflectance measurements allow in vivo measuring the optical coefficients of
absorption and scattering within the cortical tissue. This method, if applied to neural tissue during enhanced activity,
could allow a straightforward monitoring of the blood oxygen saturation changes occurring in the brain cortex during
hemodynamic responses. Furthermore, it may provide valuable information on possible absorption and scattering
changes occurring during stimulation. The feasibility of such measurements was investigated by carrying a preliminary
numerical study using a Monte-Carlo light propagation routine. Experimental parameters such as the geometry of the
optical probe, baseline cortex optical coefficients retrieved from the literature and anatomical characteristics of the rat
barrel cortex were used as an input for the simulations. The sensitivity of the probe to the local variations of optical
coefficients was investigated with this numerical approach. Additionally, the influence of the barrel cortex dimensions
and the probe positioning relatively to the activated region were studied for instrumental optimization purpose.
It was found that typical variations of optical coefficients can be detected if the activated region of barrel cortex
has a volume of typically 1 mm3 or larger. The decay of the probe sensitivity to changes was studied as a function of the
depth of the activated region. The results showed that the best sensitivity is achieved by placing the light injection fiber
of the optical probe aligned onto the center of the cylindrical barrel.