2015 Finalist Jeremiah Y. Cohen, Ph.D. Assistant Professor The Johns Hopkins University School of Medicine

Jeremiah Cohen joined the Brain Science Institute and the Solomon H. Snyder Department of Neuroscience at The Johns Hopkins University School of Medicine in 2014. Prior to his appointment, he was a Howard Hughes Medical Institute Fellow of the Helen Hay Whitney Foundation at Harvard University, where he studied neural circuits involved in reward in the laboratory of Naoshige Uchida. Prior to his postdoctoral work, Jeremiah Cohen completed a Ph.D. in Neuroscience at Vanderbilt University in the laboratory of Jeffrey Schall, where he studied decision making in the primate prefrontal cortex. He received undergraduate degrees in Neuroscience and Mathematics from Brandeis University. His laboratory studies neural circuits underlying reward, mood, and decision making.

Dopamine and Serotonin Signals for Reward Across Timescales
The brain uses many types of neurons with diverse connectivity to perform its functions. How can we begin to understand neuronal computation underlying behavior in the context of this heterogeneity? During his postdoctoral work in the laboratory of Naoshige Uchida, Jeremiah Cohen and colleagues developed an approach to observe the activity of identified types of neurons—dopamine-releasing or inhibitory GABA-releasing neurons in the ventral midbrain, and serotonin-releasing neurons in the dorsal raphe—while mice performed, simple, well-controlled behavioral tasks. Using this approach, they discovered that midbrain GABA-releasing neurons could provide nearby dopamine-releasing neurons with a reward expectation signal for reward prediction. This is thought to be a fundamental reinforcement signal in the brain. They also discovered that serotonin-releasing neurons can track the value of an environment on slow timescales, which could support long-term emotional behavior.

For Dr. Cohen’s full essay, see Science online at sciencemag.org.