Projects

Research overview

Our goal is to understand the neural mechanisms that support decision making and episodic memory. We investigate how neural processes underlying these functions are implemented in the rodent brain by examining discharge characteristics of neuronal ensembles in behaving animals, by examining the effects of manipulating specific neural systems on animal behavior and neural activity, and by computational modeling.

Neural basis of episodic memory

Notwithstanding intensive and extensive investigations for the past few decades, neural circuit mechanisms underlying hippocampal mnemonic processing are far from being clear. We have proposed a new model for hippocampal function—the binding-simulation-selection model—to account for new empirical findings and to make sense of why the hippocampus has evolved not only to remember but also to imagine episodes. Under this working hypothesis, we investigate how simulation-selection processes are implemented in CA3-CA1 networks, concentrating on value-dependent online and offline activities of hippocampal neurons and the role of dopamine in these processes. We also investigate hippocampal-neocortical interactions to understand how valuable sequences, that are selected by CA1, are stored as long-term memories in neocortical areas.

Neural basis of decision making

Under the broad category of decision making, we investigate functional microcircuits in the frontal cortex underlying adaptive control of behavior. Specific topics include reward-based learning, value representation, value-dependent action selection, and working memory. We investigate how different types of excitatory and inhibitory neurons embedded in the frontal cortex neural circuitry process and store information for flexible control of behavior in a way to maximize a long-term sum of rewards. 

Neural basis of autism spectrum disorder (ASD)

We investigate how ASD symptoms might be linked to abnormalities in the hippocampal and frontal cortical neural processes. Specifically, we investigate how hippocampal and frontal cortical neural activity differs between wild-type and ASD model mice under diverse behavioral settings such as perceptual decision making and social interactions.