Composite Synthesized Relaxation Oscillators: Application to Modeling of Colonic Electrical Control and Response Activity

A composite synthesized relaxation oscillator (SRO), whose output exhibits two types of interrelated rhythmic activities, is proposed. A slow rhythmic activity is present at all times, and it controls the appearance of a faster bursting activity that is not always present. The second‐order SRO dynamics for producing omnipresent and labile rhythmic activities are generalized as fourth‐order composite SRO dynamics for producing a composite rhythmic activity. To illustrate the relevance of this composite SRO to gastrointestinal electrical activities, a population of coupled SROs, which has been previously used to model colonic electrical control activity, is generalized to represent a population of coupled composite SROs to model both electrical control and response activities in the colon.