A striking feature of prefrontal cortex (PFC) neurons is their functional diversity, which likely is crucial to their ability to control behavior in an adaptive and flexible manner. This functional diversity is manifest in two ways. First, the activity of PFC neurons is modulated by a wide variety of cognitive and behavioral tasks. Second, within any given task, PFC neurons display a variety of behavioral and task-related firing patterns that defy easy characterization. The overall goal of TP3 is to uncover organizing principles underlying these two aspects of response diversity in PFC neurons. On the one hand, we will ask to what extent the diversity of PFC neuron responses within a given task reflects the different projection targets of PFC neurons. On the other hand, we will examine to what extent different behaviors that have been associated with the PFC engage independent or overlapping ensembles of PFC neurons. Thus, by comparing PFC neuronal activity across behavioral tasks and projection targets, TP3 will address core hypotheses 1 and 2 of the consortium and provide insights into the factors that shape the response diversity of PFC neurons and their organization into ensembles guiding flexible behavior.