Section: B4
Clicker ID: 855DDC
1. List the stages of the sleep cycle, and explain why they differ. b) Name four
possible reasons why we dream. c) Identify the major sleep disorders.
There are four stages of the sleep cycle. Stage 1 sleep occurs first in all of the sleep cycles
and it includes pictures that are like hallucinations which are sensations that occur without
any stimuli. This is the lightest stage of sleep, since it occurs first and you can be woken up
with little effort. During stage 1 sleep, there is also hypnagogic sensations which are when
you feel like you are falling/floating during your sleep. Stage 2 sleep is a deeper stage of
sleep and during this stage there are sleep spindles. Sleep spindles are short bursts of brain
activity that occur during stage two sleep. Stage 3 sleep is when it is very hard to wake you
up because your heart rate, body temperature and blood pressure decreases more. During
this stage the brain gives off delta waves; stage 3 is deep sleep and it has a duration of
about 30 minutes. Stage 4 sleep is the deepest stage and it lasts for the same amount of time
as stage 3 sleep. The body barely moves during this stage as the body is completely
relaxed. One possible reason as to why we dream is that dreams let us process our daily
events and form memories; dreams are necessary for processing information. Second, it
helps with mental development since you dream based on your understanding of the world.
Another theory on why we dream is Freud’s “wish fulfilment” theory: dreams show us the
feelings that we can’t express in reality, dreams show past memories with a deeper
meaning. Another reason is that dreaming helps with the activation of neurons. During
REM sleep, neurons process memories which turn into stories. Some psychologists think
that dreaming is just necessary to keep the neural connections using brain stimulation in
REM sleep. There are six major sleep disorders. One sleep disorder is insomnia which is
when you can’t go to sleep and the opposite of this sleep disorder is narcolepsy in which
the person can’t control when the go to sleep. Another disorder is sleep apnea which is
when a person stops breathing while they’re sleeping. Night terrors occurs when a person
wakes up terrified and they are in a state of duress. Two more sleep disorders are
sleepwalking and sleeptalking.
2. Sleep researcher William Dement said that a large sleep debt “makes you stupid” (1999,
p. 231). What are some of the ways sleep deprivation can affect cognitive performance?
Sleep deprivation can affect cognitive performance. Sleep deprivation leaves one feeling super
tired and irritable. Not getting enough sleep negatively affects your concentration, productivity,
and your ability to remember things. In the long term, sleep deprivation can lead to a depressed
state, weight gain/weight loss, lower immune system, and pain in your limbs. Also, there is a
decrease in the rate at which you can react to your environment, leaving the person to be more
likely to be involved in an accident. So, William Dement’s quote saying “a large sleep debt