This research area is concerned with how cells behave when connected together to form neural networks, and thus forms the link between molecular and systems neuroscience. We are now poised to explain how the activity of groups of cells in the brain contributes to specific behaviors, and how patterns of activity in groups of cells arise based on the properties of individual cells in the network. Nonlinear interactions between voltage and ligand-gated channels, second messenger systems, exocytosis, and other processes dictates that these networks will not just be the sums of their parts, but will produce unexpected and complex patterns of activity. Faculty address these questions in a diverse array of systems. For example, researchers investigate how sensory stimuli are extracted in the periphery, processed in parallel, and reunited centrally to form cohesive percepts, and how this information is used to plan and execute motor output. Faculty are also investigating how cortical circuits are reorganized during learning, how memories are stored and retrieved, and what goes wrong with these processes in pathologies such as epilepsy and Parkinson’s diseases. Others study the pattern generating circuitry controlling locomotion and breathing. The circuit-based mechanisms underlying stress responses, waking and arousal, and neuroendocrine regulation of the cardiovascular system are also being addressed. Students have the opportunity to learn state-of-the art techniques for monitoring activity and assaying connectivity within neural networks, including simultaneous patch clamp recordings from visually identified cell pairs and triplets, single and multiple cell staining, imaging with voltage and calcium-sensitive fluorescent dyes, electrophysiological recordings, in vivo, and neural network modeling.