Independent Fellows

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Yevgeniy Sirotin, Ph.D.

Leon Levy Presidential Fellow in Neuroscience
Shelby White and Leon Levy Center for Mind, Brain and Behavior

Dr. Sirotin is interested in understanding how neural activity is linked to perception. We use our olfactory system to detect, identify and respond to odors in our environment, yet little is known about how odor information is encoded in the brain. Dr. Sirotin is studying how simple olfactory perceptual phenomena such as odor intensity may be represented by neurons in the olfactory bulb. He uses a combination of experiments in humans, which provide excellent perceptual reports, and rodents, which are accessible for neurophysiologic studies.

In previous work at Columbia University, Dr. Sirotin studied how signals acquired in medical neuroimaging techniques, such as fMRI, relate to underlying neural activity. When performing daily tasks, some aspects of brain activity must relate to sensory input while others must link this into a higher order task representation. Dr. Sirotin found that while the majority of local neural spiking activity was tightly linked with sensory input, a large component was instead tightly linked to task structure, likely reflecting ongoing psychological processes associated with task performance not reflected in local spiking. This work demonstrated that the imaging signal reflects a linear combination of well understood local sensory evoked neural spiking as well as higher order task representations of unknown neural origin.