2. Our brain releases the hormone cortisol when we are
lacking a certain amount of sleep, and treats this
deprivation as a stressor. The release of cortisol will
damage our immune system, eventually.
When we do not sleep well, our brain functions below
its capability, impairing our judgment, and produces
slower reaction times.
Certain parts of our brain stem respond to fatigue and
diurnal rhythms (our 24 hour cycle) by regulating sleep
and wakefulness.
Cerebrospinal fluid that surrounds our brain begins to
accumulate SRS proteins (sleep regulatory substances)
which induce sleep when the proteins reach a certain
concentration level.
The amount of sleep needed per night depends on
each individual’s age, health, and sleep patterns.
Infants need 16 hours a day, teenagers need 9 hours,
and adults function best when they get 7-8 hours of
Image retrieved from
sleep per night (Sweeney, 2009). http://www.steadyhealth.com/articles/Impact_of_sleep_deprivation
_on_our_body_a659.html
3. Stages 1 – 4 (NREM – Non Rapid Eye Movement)
Stage 1: Light Sleep, muscle contractions can still be initiated and sleeper can be woken up easily.
Stage 2: Consists of about 50% of an adult’s sleep cycle, eye movement seizes and activity within
the brain decreases.
Stage 3: Delta waves, or extremely slow brain waves, begin to appear.
Stage 4: Brain activity consists predominantly of delta waves (Sweeney, 2009).
Stages 3 and 4 - deep layers of sleep - if awakened during these stages, the subject is very groggy.
Image retrieved from personal collection
4. Stage 5 (REM)
REM occurs approximately 90 minutes after falling asleep.
Accounts for 50% of an infant’s sleep, and 30% of an adult’s.
Dreaming occurs during REM
The cerebral cortex paralyzes the limbs during this dream state to keep the sleeper from acting out
their dreams.
Once REM is completed, the cycle repeats. The longer you sleep, the longer REM stage and
Stages 3 & 4 lengthen (Sweeney, 2009).
Image retrieved from http://www.cartoonstock.com/directory/R/REM_sleep.asp
5. Each year, 40 million Americans suffer from chronic sleep disorders.
20 million additional Americans suffer from occasional sleep problems.
(National Institute of Neurological Disorders and Stroke)
Next, I will discuss sleep deprivation, and then talk about the four most common sleep disorders.
These will include sleep apnea, restless legs syndrome, insomnia, and narcolepsy.
Image retrieved from http://www.sleepyage.com/sleep-disorders-overview
6. 26% of people in a survey consisting of 79,625 Americans with sleep problems were more likely
to report symptoms of depression and anxiety along with adverse health problems.
Studies indicate that people who are deprived of sleep for 56 hours, in addition to depression
and anxiety symptoms, also reported paranoia.
According to the American Psychological Association, people who are sleep deprived may
experienced slowed speech, flattened emotional responses, and apathy (Barnett, 2008).
Image retrieved from http://drbinningsdose.com/2011/06/
7. • Sleep apnea patients suffer from a reduction in oxygen to the brain due to a lapse in breathing
during sleep. The neurocognitive signs of this reduction in oxygen to the central nervous
system include personality alterations, daytime sleepiness, impaired concentration, memory,
communication, and learning.
• Studies show that even with patients suffering from acute sleep apnea, the neuronal circuitry
in their brain were changed. Animal studies have shown that the lack of oxygen to the brain
causes learning and memory impairment and neuronal death (Aviles-Reyes, et al., 2007).
Image retrieved from http://www.glasbergen.com/cartoons-about-bedtime/
8. • Affects 12 million Americans – may occur at any age, but most common in the elderly.
• Evidence suggests that RLS is related to a dysfunction in the brain’s basal ganglia circuit that
use the neurotransmitter, dopamine. Dopamine helps regulate smooth muscle activity and
movement. Disruption in this circuit would result in an uncontrollable urge to move their legs
(NINDS).
• The National Institute of Neurological Disorders and Strokes suggests that there is evidence that
low levels of iron in the brain may also be the cause of restless legs syndrome.
Image retrieved from http://bilbosrandomthoughts.blogspot.com/2009/06/cartoon-saturday_27.html
9. • 60 million Americans report having insomnia frequently or for long periods of time. Insomnia
increases with age and affects 40% of women and 30% of men (NINDS).
• Research has found that people who suffer insomnia possibly have 25-30% less gamma-
aminobutyric acid than people without insomnia. Gamma-aminobutyric acid, or GABA, is a
neurotransmitter that helps regions in the brain shut down by reducing electrical activity.
• Without the adequate amounts of GABA, the brain is unable to slow down which makes sleeping
extremely difficult. It is inconclusive whether it is the lack of GABA that causes insomnia, or that
insomnia causes the reduction in GABA (Mehta, 2008).
Image retrieved from http://sleepnosleep.wordpress.com/
10. • People affected by narcolepsy may experience several sleep
“attacks” per day. These attacks may occur at any time of day,
including during activities such as driving or even during a
conversation.
• Narcolepsy is a neurological disorder that can begin at any
age, but usually develops between the ages of 10 and 25
years old.
• The brain peptide, hypocretin, appears to be deficient in most
cases concerning narcolepsy with cataplexy (sudden loss of
muscle tone that is triggered by emotions). Hypocretin is a
neurotransmitter found in the dorsolateral hypothalamus that
regulates sleep/wakefulness, arousal, and appetite. A
deficiency in this peptide can lead to abnormalities in its
function, which can cause narcoleptic symptoms (Peacock &
Benca, 2010).
Image retrieved from http://www.cartoonstock.com/directory/n/narcoleptic.asp
11. If you are curious as to whether you may or may not have a sleeping disorder, click here.
Below is a link to a YouTube video that I found quite interesting regarding a man diagnosed as a Narcoleptic with
Cataplexy.
Narcolepsy Video
Below is a 20 minute video, if you are interested, on SHY (Synaptic Homeostasis Hypothesis) presented by Dr.
Tononi of University of Wisconsin, Madison.
SHY
Thank you for taking the time to go through my PowerPoint. I hope that I have informed you of some new
information on sleep and sleep disorders.
12. Aviles-Reyes, R., Angelo, M., Villarreal, A., Rios, H., Lazarowski, A., & Ramos, A. (2010). Intermittent Hypoxia During Sleep
Induces Reactive Gliosis and Limited Neuronal Death in Rats: Implications for Sleep Apnea. Journal Of Neurochemistry,
112(4), 854-869.
The information retrieved from this scholarly journal was used to summarize basic knowledge of the sleep disorder,
sleep apnea and its effect on the brain.
Barnett, K. J. (2008). The Effects of a Poor Night Sleep on Mood, Cognitive, Autonomic, and Electrophysiological
Measures. Journal of Integrative Neuroscience, 7 (3), 405-420.
This information retrieved off this academic journal consists of a study performed regarding sleep deprivation and
its cognitive effect on the subjects. Information was retrieved on the EBSCO database.
Brain Basics: Understanding Sleep. National Institute of Neurological Disorders and Stroke, Bethesda, MD. 2007.
Web.
This information retrieved off of the National Institute of Neurological Disorders and Stroke website consists of
basic statistical information regarding sleep disorders in the United States.
Mehta, A. (2008). Insomnia Tied to Lack of Brain Chemical. The Dana Foundation. Web.
The information retrieved off this website summarizes a possibility that the lack of the neurotransmitter GAMA is
responsible for the sleep disorder, insomnia.
Peacock, J., & Benca, R.M. (2010). Narcolepsy: Clinical Features, Co-morbidities & Treatment. Indian Journal of Medical
Research, 131 (2), 338-349.
The information retrieved from this article summarizes the condition known as narcolepsy. It also explains
the possible causes behind the disorder, hypocretin.
13. Sleep. American Psychological Association, Washington D.C. 2012. Web.
The information derived from the American Psychological Association website was used solely to reference
information listed on the Sleep Deprivation slide in this PowerPoint.
Sweeney, Michael S. (2009). Brain: The Complete Mind. National Geographic Society, Washington, D.C. 188-189.
I retrieved the necessary information on the stages of sleep from our textbook, Brain: The Complete Mind.
I summarized the information on Stages 1-5, including both Non-Rapid Eye Movement stages and Rapid
Eye Movement during our sleep cycle.