ICLM: Discover, teach, treatI.C. Learning & Memory

Stacks Image 7

Melissa Sharpe

In the lab we are interested in the neural circuits that help us develop cognitive models of our environment. These models allow us to learn from our experience and make decisions in the future more effectively. We have a particular interest in how dopamine neurons in the midbrain relay a teaching signal to the rest of the brain to allow the lateral hypothalamus and prefrontal cortex to develop learned associations that contribute to different aspects of our cognitive models. To investigate these processes, we use sophisticated behavioral procedures in combination with optogenetics and fiber photometry. The eventual aim of this research is to understand how changes in these neural circuits contribute to aberrant cognitive models of the world in cases of psychopathology, with a particular emphasis on schizophrenia.

Selected publications:

Sharpe MJ, Stalnaker T, Schuck N, Killcross S, Schoenbaum G, Niv Y. 2019. An integrated model of action selection: distinct modes of cortical control of striatal decision making. Annual Review of Psychology, 70(1).

Sharpe, M. J., Chang, C. Y., Liu, M. A., Batchelor, H. M., Mueller, L. E., Jones, J. L., Niv, Y. & Schoenbaum, G. (2017). Dopamine transients are sufficient and necessary for acquisition of model-based associations. Nature neuroscience, 20(5), 735.

Sharpe, M. J., Marchant, N. J., Whitaker, L. R., Richie, C. T., Zhang, Y. J., Campbell, E. J., Koivula, P.P., Necarsulmer, J.C., Mejias-Aponte, C., Marisela M., Pickel, J., Smith, J.C., Niv, Y., Shaham, Y., Harvey, B., & Schoenbaum, G. (2017). Lateral hypothalamic GABAergic neurons encode reward predictions that are relayed to the ventral tegmental area to regulate learning. Current Biology, 27(14), 2089-2100.

Nasser, H. M., Calu, D. J., Schoenbaum, G., & Sharpe, M. J. (2017). The dopamine prediction error: contributions to associative models of reward learning. Frontiers in psychology, 8, 244.
Sharpe, M. J., Wikenheiser, A. M., Niv, Y., & Schoenbaum, G. (2015). The state of the orbitofrontal cortex. Neuron, 88(6), 1075-1077.

Sharpe, M. J., & Killcross, S. (2015). The prelimbic cortex directs attention toward predictive cues during fear learning. Learning & Memory, 22(6), 289-293.

Sharpe, M. J., & Killcross, S. (2012). The prelimbic cortex contributes to the down-regulation of attention toward redundant cues. Cerebral cortex, 24(4), 1066-1074.

Lab website and all publications: https://sharpelab.psych.ucla.edu/