Chapter 10: Biological Rhythms and Sleep Flashcards
biological rhythm
a regular fluctuation in any living process
circadian rhythm
a pattern of behavioral, biochemical, or physiological fluctuation that has a 24-hour period
ultradian
reffering to a rhythmic biological event with a period shorter than a day, usually from several min to several hours long
infradian
referring to a rhythmic biological event with a period longer than a day
free-running
referring to a rhythm of behavior shown by an animal eprived of external cues about time of day
phase shift
a shift in the activity of a biological rhythm
entrainment
the process of synchronizing a bio rhythm to an environmental stimulus
zeitgeber
the stimulus that entrains circadian rhythms
suprachaismatic nucleus (SCN)
a small region of the hypothalamus above the optic chiasm that is the location of the circadian clock
retinohypothalamic pathway
the route by which retinal ganglion cells send their axons to the SCN
melanopsin
a photopigment found in those retinal ganglion cells that project to the SCN
Clock and Cycle
two proteins that bind together to form a dimer that binds to the cells in DNA to promote transcription of other genes, and the proteins made go back and inhibit the action of clock and cycle
EEG
the recording of gross electrical activity of the brain via large electrodes placed on the scalp
rapid eye movement
small amplitude, fast EEG waves, rapid eye moves
biological functions of sleep
- energy conservation 2. niche adaptation 3. body and brain restoration 4. memory consolidation
