PSYC 111 Chapter 3 Notes

Body Rhythms and States of Consciousness

True or false exercise
 Snoring is bad for your health- could indicate sleep apnea. Risk factors include:
o Obesity
o Most common person with this: middle aged man
 Sleep disorders are often genetic

Sleep and dreaming
 Learning Goals
 Definitions of Sleep:
 Why we sleep
 Why we dream
 Sleep disorders
o Sleep paralysis- when a person is conscious but paralyzed for a few minutes when coming out of
sleep
o Fatal Familial Insomnia
 Affects the thalamus
 Dominant genetic disorder (Codon 178 is a gene associated with prion disorders
causes buildup of misfolded proteins in the brain)
 Stop being able to sleep, incurable and untreatable, leads to death
 Developmental differences in sleep
 Cultural differences in sleep practices
 Body Rhythms
 Sleep cycle
o Non rem 1(rapid brain activity)
 Some people get a sense of falling
o Non rem 2,
 Sleep spindles
o Non rem 3
 Delta waves during sleep
 “Deep Sleep”-very hard to wake someone up
o REM
 Dreaming,
 Body is supposed to be paralyzed
 Also called paradoxical sleep
o One cycle takes 90-120 minutes
o As night goes on you could lose REM sleep or deep sleep

,  Why do we sleep?
o Sleep deprivation
 There were problems with people who were deprived of sleep
 Don’t perform as well on cognitive tests after 1 night
 2 nights worse
 3 nights- can’t stay awake
 After 3 nights, you begin to hallucinate
 Sleep as a restorative process
o When kids sleep they release growth hormones
 Sleep as a clock driven process
o Circadian Rhythm (may be driven by ganglion cells in the eyes)
 Sleep/ wake cycle is daily
 Sleep stage cycles happen 4-5 times a night
 Driven by specialized ganglion cells in eyes
 Sleep Hygiene: making the environment as good for sleep as possible
o Includes making the room dark

 Body Rhythms
o Circadian (about every 24 hours)
o Tiredness depends on time of day
o Flying disrupts circadian clock
o Reason why night shifts are difficult
 Setting the circadian clock is called “photoentrainment”
 Ganglion cells in the eye that may be responsible for photoentrainment contain the pigment
“melanopsin”
 “Melatonin” secreted by the pineal gland, levels are affected by light levels.
o Rises during sleep in a darkened room
o Falls in a lighted room upon waking
 Why do we sleep?
 Sleep as an evolutionary relic
o We sleep at night because evolutionarily, this kept us safe from predators (seeked shelter and
were still)
o Conserves resources because less calories are burned
o
 Daily Sleep Time in Animals
o Giraffe 1.9
o Elephant3.1
o Pilot Whale5.3
o Cat 12.5
o Chipmunk 15.8
o Brown Bat  19.9
o Predators tend to sleep more, large animals tend to sleep less

Sleep Disorders
 Insomnia
o 1/10 to 1/3 people have insomnia
o More likely to affect women