Professor Harnett studies how the biophysical features of individual neurons, including ion channels, receptors, and membrane electrical properties, endow neural circuits with the ability to process information and perform the complex computations that underlie behavior. The laboratory focuses on the role of dendrites, the elaborate tree-like structures through which neurons receive the vast majority of their synaptic inputs. The thousands of inputs a single cell receives can interact in complex ways that depend on their spatial arrangement and on the biophysical properties of their respective dendrites. For example, operations such as coincidence detection, pattern recognition, input comparison, and simple logical functions can be carried out locally within and across individual branches of a dendritic tree. Harnett addresses the hypothesis that the brain's computational power arises from these fundamental integrative operations within dendrites. He focuses in particular on sensory processing and spatial navigation, with the goal of understanding the mechanistic basis of these brain functions.