Ilana Witten, Ph.D. (Princeton)
Princeton Neuroscience Institute
Specialized and spatially organized dopamine signals
I will describe our recently published work showing surprising heterogeneity at the single-cell level in the dopamine system based on 2-photon calcium imaging during a virtual reality decision-making task, contradicting a classic view of a homogenous reinforcement signal in the dopamine system. I will then show newer unpublished work showing that spikes can be accurately inferred from calcium imaging in dopamine neurons, which suggests that the recording modality is not the source of the discrepancy with the classic view. Finally, I will discuss new work in collaboration with Nathaniel Daw attempting to reconcile this newly observed heterogeneity with classic models regarding the neural instantiation of reinforcement learning.
Ilana Witten graduated from Princeton University with an A.B. in physics in 2002, and received her Ph.D. in neurosciences from Eric Knudsen’s lab at Stanford University in 2008. She subsequently completed a postdoctoral fellowship in Karl Deisseroth’s lab in the Department of Bioengineering at Stanford. At Princeton University, her lab studies the neural circuits for reward learning and decision-making, with a focus on the role of dynamics and feedback in these cognitive processes. Her work has been recognized with a Helen Hay Whitney fellowship, Sloan Foundation fellowship, Pew Scholars award, McKnight Scholars Award, NIH New Innovator Award, NARSAD Young Investigator award, and Daniel X. Freedman prize.