Department or Program
Primary Wellesley Thesis Advisor
Conscious processes such as attention and sensory awareness have been associated with neural oscillations in the gamma frequency range (30-90 Hz). However, it remains unclear whether gamma rhythms play a functional role in sensory routing or are merely a byproduct of computation. Optogenetics has recently made it possible to manipulate synchrony exclusively in vivo. Therefore, to test the hypothesis that local gamma synchrony plays a functional role in routing sensory responses between brain regions, we launched an optogenetics protocol in mice to induce gamma synchrony in primary somatosensory cortex (S1) and measure somatosensory responses in frontal cortex (M2). To test the feasibility of our experimental setup we also carried out recordings in control mice and analyzed the relationship between spontaneous fluctuations in pre-stimulus S1 gamma synchronization and M2 response amplitudes. Our pilot experiments confirmed our ability to elicit and record sensory responses in anesthetized mice but initial analyses reveal no correlation between S1 synchrony and M2 response amplitude. Preliminary optogenetic experiments were unsuccessful in inducing synchrony but revealed the possible causes of the problem and the steps necessary to address them. Once we can successfully manipulate synchrony we can apply the analyses developed for control recordings to address the question of whether gamma synchrony modulates interarea signal transmission in the brain.