sleep stages and sleep disorders

2. Sleep order
• There are five phases of sleep.
• They are 1, 2, 3 and 4 stages with REM as the last
one.
• When you are sleeping you are begin at stage 1
and then go through each stage until reaching REM
SLEEP then you begin the cycle again.
• Each stage cycle circle – 90 to 110 minutes.
• Your brain acts differently in each stage of sleep.
In some person it occurs as bodily movements and
in others immobility.

3. Stage – 1
•Light sleep
•Experience drifting in and out if the sleep.
•Can easily woken up
•Eye movements and body movements slow
down.
•May experience sudden jerky movements of
your legs and other muscles which is known
as hypnic myoclonia or myoclonic jerks.
•Sleep starts gives a sensation of falling which
is caused due to spontaneous stimulation of
motor areas.

4. Stage – 2
•Between 45 % to 55% of your sleeping is spent
in this stage
•eye movements and stops and brain waves
stops
•Sleep spindles may occur.
Stage – 3
•It is the first stage of deep sleep.
•The brain waves are the combination of slow
waves (delta waves) combines with faster waves.
•It is also difficult to wake up someone in this
stage.
•If you woken up during this stage, you may feel
groggy and disoriented for several minutes.

5. Stage – 4
•2nd stage of deep stage.
•Brain waves making slow (almost
exclusively)
•It is also difficult to waking up
someone in this stage.
•Both the stages are important
feeling refreshes in the morning.
•If these stages are too short, sleep
will not feeling satisfying.

6. REM SLEEP
Sleep stage in which dream occurs.
when enters into REM, breathing becomes fast irregular and shallow.
Your eyes moves rapidly and your muscles becomes immobile.
Heart rate, and blood pressure increases.
Men may develops erections.
About 20% of sleep in REM sleep occurs for adults.
These sleep phase begins about 70 to 110 minutes after you fast asleep.
The first cycle has short or phase of REM sleep.
Towards morning, the time spent in REM increases with deep stage
decreases.
Researches do not fully understand REM sleep and dreaming. They knew it
is important in the creation of long term memories.
 If person’s REM sleep is disrupted, the next stage cycle doesn’t follow
normal order.
But, often goes directly to REM sleep until the previous night’s lost REM is
made up.

7. Important function of REM sleep
 It contributes to learning and memory
consolidation, although the research is not
conclusive.
 Specifically, it may help someone to learn a new
skills.
Eg: learning how to ride a bicycle.
 As it differs from factual, or semantic memory
such as memorizing a list of vocabulary words.
 Beyond , its role in procedural memory it is
hypothesized that REM sleep may also have a role in
problem solving.
 Unique connections may be made within the
brain, allowing novel discoveries to be made.

8. The vivid dreams of REM,
often experienced like a
movie unfolding in which the
sleeping person is an actor in
the story.
When the content of the
dream is disturbing, night
mares as may result.

9. Lucretius
Approx 2000 years ago postulated that
sleep is the absence of wakefulness.
Aristotle- Greek philosopher
•Sleep was an event of consciousness in
the heart.
•He connected the digestive process with
the onset of sleep as well.
1900 Neurons- basic unit of nervous system.
1903 First sleep pill barbital was introduced
1911 ( henri pieron et al.,)
•Found that sleep deprived animals
apparently secreted the sleep inducing
molecule into the cerebrospinal fluid
which could make alert dogs fall into a
deep sleep when injected with them.
•“HYPNOTOXIN”.
•Two years later he published first book
to deal with physiology of sleep.
History from then to now…

10. 1925
 It was the start of research of one distinguished
workers in the field, Nathaniel Kleitman.
 He discovered the existence of rapid eye
movement sleep an went on to study sleep and
wakefulness.
 Cerebral cortical activity in mentation,
consciousness, voluntary movement and the effect
of sleep deprivation.
1935 (Bunning -
German researcher)
•Recognized the existence of biological clock, and
found that it is inherited in each species.
1924
EEG – electroencephalogram was invented but it
was published only after 5 years in which the
concept was validated.
The differing in brain electrical waves during sleep
and wakefulness was discovered during this process,
stimulants began be to be used to promote
wakefulness in narcolepsy patients.

11. 1953 •REM sleep was first
detected in the young boy.
1959 –
(Michael jovet)
•Crucial distinction was
made between REM and
NREM sleep
1968
(Roger
broughton)
•Parasomnia and bed
wetting were identified to
be product of confusional
awakening from slow
waves sleep rather than
REM sleep

12. 1980
Connection between
circardian rhythm and
duration of sleep was
determined as well as
with other cues.
1990
Saw emergence of
numerous working
theories of sleep
including neuronal group
and brain energy
metabolism theory.

13. DSM – 5 classification
•Insomnia
Trouble in falling and / or staying asleep .
It may acute or chronic which varies from one person to
another.
•Hypersomnolence disorder
Significant episodes of sleepiness even after having 7
hours or more of quality sleep.
•Narcolepsy
Excessive sleepiness, sleep paralysis hallucinations and
some episodes of cataplexy (loss of muscle control)
•Breath related sleep disorder
•Central sleep apnea
•Sleep related hypoventilation

14. •Circardian rhythm sleep wake disorders
Desynchronize between sleep – wake
rhythms and the light - darkness cycle.
•Parasomnias
Unwanted events are experience that
occurs while you are feeling asleep, sleeping
or waking Up.
•Non – REM sleep disorder arousal partly in
Non – REM sleep and partly awake enough to
perform complex activities without any
conscious awareness of them. This occurs
during slow wave sleep.
•Substance / medication induced sleep
disorder.

15. Common causes of sleep disorder
Factors that cause sleep problems include:
•Physical distribution (eg : chronic pain from
arthritis, head ache and head ache and
fibromyalfia)
•Medical issues
•Psychiatric disorder (depression and
anxiety disorder)
•Environmental issues (its too bright, or
your partner snores)

16. Other factors:
•Genetics
•Night shift - people who work at night
often experience sleep disorders as their
activities run contrary to the biological
clocks.
•Medication – many drugs can interfere
with sleep such as antidepressant, blood
pressure, medication and also medicine
for cold.
•Aging – about half of all age of 65 have
some sort of sleep disorder.