PSL300H1 Final: L32 Circadian Rhythms & Learning

• School: UTSG
• Department: Physiology
• Course: PSL300H1
• Professor: Dr.Buchan, Dr.Kee, Dr.Tweed

Document Summary

We(cid:859)(cid:448)e (cid:271)ee(cid:374) talki(cid:374)g a(cid:271)out si(cid:373)ple (cid:396)efle(cid:454)es, (cid:448)olitio(cid:374)al (cid:373)o(cid:448)e(cid:373)e(cid:374)t a(cid:374)d (cid:272)o(cid:373)ple(cid:454) (cid:373)o(cid:448)e(cid:373)e(cid:374)ts (cid:449)ith the (cid:272)o(cid:396)te(cid:454), the auto(cid:374)o(cid:373)i(cid:272) (cid:396)efle(cid:454)es. Governed by neuronal oscillator with near-24h period. Entrained to exact day-night cycle by retinal input from ganglion cells with melanopsin. Retinal projection to: suprachiasmatic nucleus (scn, pretectal area sympathetic efferents superior cervical ganglion pineal body. Circadian rhythm (day and night cycle) is a 24hr oscillation of a physical parameter. Governed by neuronal oscillator, with a new 24hr cycle. There is retinal input from melanopsin retinal ganglion cells, which is the most important factor of control of circadian rhythms. We can get rid of cones and rods, and still maintain circadian rhythm, which s(cid:455)(cid:374)(cid:272)h(cid:396)o(cid:374)izes (cid:449)ith (cid:449)hat(cid:859)s happe(cid:374)i(cid:374)g (cid:449)ith ea(cid:396)th(cid:859)s (cid:396)otatio(cid:374) Peak absorbance of melanopsin is in blue-green wavelength. Retina that contains melanopsins project to the suprachiasmatic nucleus (scn), a master clock/regulator of circadian rhythm.