Three sentence research synopsis: I investigate how the brain controls activity- or state-changing rhythmic electrical activity. During physiological activity (e.g. sleep) or as a result of neural impairments (e.g. epilepsy), rhythmic activity appears across large areas of the thalamocortical system. I investigate cellular calcium signals that control the generation and distribution of such activity using a combination of two-photon laser scanning microscopy and cellular electrophysiology.