We are interested in the neural basis of higher cognitive functions, such as working memory, that enable planning and decision-making. To dissect the neural circuitry underlying these cognitive processes, we use a variety of optical approaches including two-photon calcium imaging and optogenetics to record and manipulate neuronal ensembles in behaving mice. Through experiments at the cellular and systems levels, our long-term goal is to understand how neurons in the cortex process information and why dysfunctional circuits may lead to the cognitive deficits associated with psychiatric disorders.