Circadian rhythm: population of interacting neurons.
The circadian rhythm in the requency of compound action potentials recorded from the isolated eye of Aplysia is a consequence of interactions among the cells of the retinal population. As the population number is reduced to a critical 20 percent, progressively shorter circadian periods and ranges are expressed. Below the critical number, the population oscillates at ultradian frequencies.
D000200:Action Potentials; D000818:Animals; D002452:Cell Count; D002940:Circadian Rhythm; D005123:Eye / Q000033:anatomy & histology / Q000294:innervation; D005246:Feedback; D066298:In Vitro Techniques; D008974:Mollusca; D009474:Neurons / Q000502:physiology*; D009900:Optic Nerve / Q000502:physiology; D010786:Photoreceptor Cells / Q000502:physiology; D012160:Retina / Q000294:innervation