fMRI and Electrophysiology of Optogenetic Vs. Whisker Stimulation in the Whisker Barrel Cortex of the Awake Rabbit

Daniil Aksenov¹, Limin Li¹, Michael Miller¹, George Iordanescu¹, Alice M. Wyrwicz¹

The recently-developed technique of optogenetic control allows precise manipulation of the excitation or inhibition of specific neuronal cell types which generate the blood oxygenation level dependent (BOLD) response measured by functional magnetic resonance imaging (fMRI). However, the properties of optogenetic BOLD have not been well characterized as compared to the BOLD signal generated through conventional sensory stimulation. The goal of this study is to compare the BOLD and electrophysiological activity produced by optogenetic stimulation vs. sensory whisker stimulation. The results indicate the importance of accounting for potential differences in BOLD signal behavior when interpreting fMRI results obtained from optogenetic stimulation.