CRCNS Research Proposal: Stability and heterogeneity in weakly synchronous cortical networks

The brain processes information by propagating electrical impulses through complex networks of neurons. Deciphering the computations supported by these networks requires determining whether neurons respond in the same fashion to the same inputs, identifying sources of observed variability in neural responses, and determining the constraints that variability imposes on information processing. Equally important is determining whether neurons act jointly or independently to encode information, as well as how many neurons must be considered in order to extract meaningful information or to change behavioral responses. This project aims to address these longstanding issues via a combination of experimental and analytical techniques. Previous research has considered the brain as operating in a regime whereby neurons exhibit independent variability in their responses. By contrast, the investigators aim to build on recent research demonstrating that a key determinant of the physiological neural response is a weak but detectable form of synchrony. In this project, they characterize the emergence and persistence of synchrony in realistic neuronal networks, as well as its role in maintaining neural functions. A hallmark of realistic neural networks is that they exhibit a high degree of heterogeneity, involving various dynamical timescales and cellular components. Accordingly, the core objective of the project is to explain how heterogeneities shape synchrony and how this resulting synchrony may ensure a physiological regime of operation. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.