A coupled oscillator feedback system as a model for the photoperiodic clock in insects and mites. I. The basic control system as a model for circadian rhythms

✍ Scribed by M. Vaz Nunes; R.D. Lewis; D.S. Saunders

• Publisher: Elsevier Science
• Year: 1991
• Tongue: English
• Weight: 764 KB
• Volume: 152
• Category: Article
• ISSN: 0022-5193
• DOI: 10.1016/s0022-5193(05)80195-x

✦ Synopsis

A control systems model for the photoperiodic clock is developed, which is an extended version of the earlier published "damped circadian oscillator model", and which consists of two feedback circadian oscillators, a "pacemaker" and a "'slave", both entrainable by light and by temperature. The pacemaker is self-sustained or slightly damping, and the slave, which is coupled to the pacemaker, is strongly damped. The coupling is such, that with stronger coupling the slave's amplitude increases and the oscillation becomes less damped. In the first paper we demonstrate that the model is capable of describing many features of circadian rhythms, such as the occurrence of transients in constant darkness after a single light pulse, temperature-compensated shapes of phase response curves of both type 1 (weak resetting) and type 0 (strong resetting), and changes in pacemaker-slave phase relations when entrained by light-dark cycles with increasing photophases.