Biopsychology 8/15 Flashcards
Rapid eye movement (REM sleep)
A kind of sleep that occurs at intervals during the night and is characterised by rapid eye movements, more dreaming and bodily movement, and faster pulse and breathing.
Exogenous cues for circadian rhythms.
Day light. Social cues - meal times, bed times ect.
Examples of a circadian rhythm.
Sleep/wake cycle and body temperature.
Exogenous cues for infradian rhythms
Pheromones and light.
Suprachiasmatic nucleus (SCN)
Tiny bundle of nerve cells located in the hypothalamus in each hemisphere of the brain where the optic nerves from each eye cross. The primary endogenous pacemaker in mammals. Receives info directly from this structure.
Melatonin
Produced by pineal gland at night, governs sleep/wake cycle. Production inhibited during periods of wakefulness.
Light
A zeitgeber in humans that can reset the main endogenous pacemaker (SCN) and plays a role in the sleep/wake cycle.
Social cues entraining circadian rhythms.
Schedules created by others, e.g. mealtimes and bedtimes. Circadian rhythms start at 6 weeks. Most babies entrained by 16 weeks. Schedules imposed by parents are a key influence. Adapting to local eating and sleeping times is an effective way of entraining circadian rhythms and beating jet lag.
Zeitgebers
External factors in the environment that reset our biological clocks through a process called entrainment.
Light as an exogenous zeitgeber.
One of the most dominant EZs; resets body’s pacemaker through SCN. May explain why Campell and Murphy found that shining lights on knees caused a shift in circadian rhythm.