Grant: Operating Grant

Over a century ago, Santiago Ramon y Cajal postulated the law of dynamic polarization according to which dendrites represent a receiving apparatus of the neuron specialized in integrating and processing the vast majority of synaptic inputs. Since then, the large structural diversity of dendritic arbors in different types of neurons has captivated the imagination of scientists. In addition to morphological complexity, dendrites exhibit a highly complex functional organization. They are endowed with multiple ion conductances, which are able to control the integration and propagation of local and global dendritic signals in a highly dynamic manner. Two types of signals are generated in dendrites: electrical and chemical. Both can be highly compartmentalized within individual dendritic branches and synaptic specializations, providing a means for the highly selective integration and modification of incoming information. However, despite the tremendous progress in dendrites research, we still do not understand the nature of computations performed by neuronal dendrites and, more importantly, their relevance to the operation of a particular neuron within its local circuitry. Here, we will use a combination of optophysiological, optogenetic and computational tools in brain slices and in behaving animals in vivo to determine the relationship between the distribution of dendritic conductances and the function of dendrites in a genetically defined population of cortical inhibitory interneurons that play a crucial role in the generation of brain rhythms and are affected in epilepsy, schizophrenia and autism. We will establish the rules of dendritic integration and the role of dendritic computations in the operation of interneurons during behavior in animals navigating in virtual environment. The results of the study will be important to connect the computations performed by single neurons to the operation of its local network, and higher-level brain function and malfunction.