In the first half of my talk, I will discuss our recent work on the midbrain dopamine system. The hypothesis that midbrain dopamine (DA) neurons broadcast an error signal for the prediction of reward is among the great successes of computational neuroscience. However, our recent results contradict a core aspect of this theory: that the neurons uniformly convey a scalar, global signal. I will review this work, as well as our new efforts to update models of the neural basis of reinforcement learning with our data. In the second half of my talk, I will discuss our recent findings of state-dependent decision-making mechanisms in the striatum.


Ilana Witten is a professor of neuroscience and psychology at Princeton University. She was first introduced to neuroscience as an undergraduate physics major, when she studied neural coding in the retina with Michael Berry at Princeton. She then moved to Stanford to pursue a PhD in neuroscience, where she worked in the systems neuroscience lab of Eric Knudsen. As a postdoctoral fellow, she worked with Karl Deisseroth in the Department of Bioengineering at Stanford, developing and applying optogenetic tools to dissect the neuromodulatory control of reward behavior in rodents. Since 2012, her lab at the Neuroscience Institute and Department of Psychology at Princeton has focused on understanding the circuitry in the striatum that support reward learning and decision making. She has received multiple awards for her work, including an NIH New Innovator Award, a Mcknight Scholars Award, and the Daniel X Freedman Prize.