Biology

Shantanu Jadhav, PhD
Brandeis University

The brain has the remarkable capacity to learn and use memories to guide ongoing behavior. The hippocampus and prefrontal cortex are required for encoding, storage, and retrieval of memories, and play a key role in using past experiences to guide behavior. The physiological mechanisms that mediate hippocampal-prefrontal interactions, and the specific roles they play in memory, are therefore of great interest. These mechanisms are best studied in rodent spatial memory models, which have proven highly tractable in linking physiology to behavior. I will present recent studies about the role of specific ensemble activity patterns in mediating hippocampal-prefrontal interactions underlying memory-guided behavior. In spatial memory tasks, hippocampal place cells are active in specific regions of space during theta oscillations, as well as during sharp-wave ripples (SWRs), when place cell activity is replayed during pauses in behavior and sleep. I will focus on reactivation of behavioral representations in hippocampal-prefrontal networks during SWRs, and present physiological and causal evidence that links SWR reactivation to memory consolidation, retrieval and planning. This evidence suggests a framework in which coordination of hippocampal-prefrontal activity mediated by specific network patterns plays complementary roles at different stages in learning, supporting memory storage, retrieval, and decision making.

Relevant publications:

Jadhav et al., Science, 2012

Jadhav et al., Neuron, 2016

Reviews/ Commentaries: