Chapter 5—Body Rhythms/Mental States
Circadian rhythms (24 hour cycles)
Extroined external cues
Endogenous cues from within
Your “biological clock”:
Eye light and dark send messages to receptors in your eye which sends a message
to the SCN.
Suprachiasmatic nucleus sends a message to the brain and the body to start
1 Sleep stages (Ultradian rhythm, they are 90 minutes and you will have
many of them throughout the night depending on how much you sleep.)
Drifting in and out of sleep. Feeling of floating and falling. Easily
woken at this stage. Heart rate and breathing slow. The state
where lucid dreams happen.
If you are woken, you won’t remember being asleep. We spend
more time at this stage when we are older than younger. We
think sleep spindles are for the brains understanding for muscle
activity and/or memory consolidation.
Deep sleep. There is more relaxation. Deep breathing begins.
Muscles start to relax. Sleep walking, talking, eating occurs
during these stages of 3 or 4. No paralysis hormone.
Deep sleep. There is more relaxation. No paralysis hormone.
Sleep walking, talking and eating.
REM sleep. Dream stage.
REM ,2,3,4,3,2, REM…
remembered during the 90 minute period before and between REM sleep.
Brain waves are similar to the awake waves.
o Paralysis hormone (no sleepwalking)
o Heart rate increases.
o Rapid Eye Movements.
o Genitals are active
o Babies spend more time in REM than older adults.
REM important for memory?
Sleep Deprivation cortisol running through your body steady flow of
cortisol eats away at your organs.
2 It decreases new cell development.
Insomnia is caused by depression, anxiety, stress, drugs and alcohol.
Treatment: sedatives but they carry over effects and decrease your deep sleep.
Cognitive-Behavioural Therapy: bed is for sleep and sex only, not for reading, not
TV, or anything with lights. Do not associate stresses with your bed.
Sleep Apnea waking up feeling as though you cannot breathe.
Narcolepsy falling asleep during wakefulness due to a degeneration of
REM behaviour disorder (sleep walking) paralysis hormone did not kick
in. Children tend to grow out of it.
Theories of Sleeping & Dreaming
Sleep: consolidation of memory allows the transfer of information from
short-term memory to long-term memory. It helps us with problem solving.
o Freud’s Wish Fulfillment what we dream about happens because
the things that we think about in our dreams are too shameful to
express themselves throughout the day.
They provide insight into the unconscious because the content
is too difficult for the conscious. We dream in symbols.