SLEEP PHYSIOLOGY - ways to sleepCopy-1.pdf

Is a pdf about sleeping and sleeping only

1. UNIVERSITY:DEDEN KIMATHI UNIVERSITY OF TECHNOLOGY
COURSE:BACHELOR OF SCIENCE IN NURSING
UNIT:MEDICAL PHYSIOLOGY 1
UNIT CODE:HNS2102
LECTURER:MR. BONIFACE CHEGE
ASSIGNMENT:SLEEP PHYSIOLOGY
SUBMITTED DATE:13/09/2024

2. NAME REGISTRATION NUMBER
BEATRICE MUGO H151-01-2769/2024
AMOS WACHIRA H151-01-2812/2024
NAOMI KONES H151-01-2780/2024
CALEB KONES H151-01-2782/2024
ELSIE MORAA H151-01-2828/2024
SUSAN KIRIGO H151-01-2807/2024
ANGELINE MASWAI H151-01-2767/2024
YVONNE MAINA H151-01-2783/2024
FAITH KIRIGO H151-01-2770/2024
MAUREEN CHEPNGENO H151-01-2785/2024
ESTHER WANJIKU H151-01-2765/2024
JACINTANTHENYA H151-01-2793/2024

3. By Group 16 Members

4. Sleep is a temporary state of unconsciousness
in which the Brain is primarily responsible for
internal rather than external stimuli.
Sleep is a natural, cyclic process that is self
regulated and easily reversible to wakefulness.

5. Brain activity can be recorded through
Electroencephalogram (EEG) which measure
electrical activity in the superficial layer of the
celibrocortex.
Different stages of consciousness correspond to
different types of brain waves.

6. A fully awake and alert brain produces high
frequency and low voltage Beta waves.
As consciousness decreases, brain waves
become progressively slower in frequency and
higher in voltage.

7. There are two major phases of sleep
1.Rapid Eye movement(REM) sleep
2.Non Rapid Eye Movement(non REM) sleep

8. Non-REM sleep is divided into 3
stages:N1,N2& N3
N1-Is the transitional stage between
wakefulness and sleep.
EEG is dominated by Alpha waves
The sleeper is easily awoken by light
stimulation.
It typically lasts a few minutes

9. N2-Is the deeper sleep state
Stronger stimuli is required to wake the sleeper
Brain activity is slower and more irregular with
short burst of sleep spindles and K-complex.
It is believed that many consolidation take
place during this stage

10. N3-Deeper state than N2.
Slow delta waves are dominate.
Muscles relax and vital signs are at their lowest
and its difficult to wake the sleeper.
N3 is typically followed by N2 transition before
REM sleep occurs.

11. REM sleep is characterized by rapid eye
movement under the eye lids.
It is also known as Paradoxical sleep because
the brain`s EEG is similar to that of a wake
state.
At this state is when most dreams occur, vital
signs are up but there is a total inhibition of
skeletal muscle which prevents dreamers from
acting up their dreams(sleep paralysis).

12. This sequence repeats itself 45 times in a typical
night. As night increases, duration of N2 and
REM sleep increases while N3 decreases.
The amount and timing of sleep is regulated
by:
1)Homeostatic Drive
2)Circadian Rhythm

13. This is the body`s need for sleep/ pressure to
sleep.
It is lowest after a good night sleep then start to
build up after we awaken. It continues to rise
until sleep occurs

15. Adenosine is thought to be a substance that
accumulates with waking hours and drives the
pressure to sleep.
Interestingly, Caffeine is thought to promote
wakefulness by acting as an antagonist of
Adenosine.
Need to sleep accumulates with illness and
physical demanding activities

16. This is the body`s biological clock for sleep
wake cycle. It determines the timing of sleep.

17. The master clock is located in the
Suprachiasmatic Nucleus(SCN) of the
Hypothalamus. It receives light inputs from
Retina and resets the clock everyday
accordingly to the day/night cycle.
SCN is more active during the day than at
night.
Sleep promoting region is located at the
Ventralateralpreopticnucleus(VLPO) of the
hypothalamus. It is inhibited by SCN and
activated by Adenosine(sleep pressure).

18. VLPO uses GABA to inhibit wake promoting
regions of the brain which include:
-Multiple nuclei in the reticular formation.
-posterior hypothalamus.
Of these regions it`s important to note the :
Tuberomammillary nucleus(TMN)
Hypocritine neurons
The TMN consist mainly of Histamine allergic
neurons which produce GABA which inhibit
VLPO in return

19. This mutual inhibition is the basis of the switch
between sleep and awake state.
The Hypocritine neurons stimulate TMN and are
crucial for maintaining wakefulness.
Loss of these neurons result in Narcolepsy
(excessive uncontrollable daytime sleepiness).
During the day SCN inhibit VLPO and stimulate
Hypocretin neurons driving the switch toward
waking state.

20. By the end of the day when SCN activity is
lowest and pressure to sleep is highest VLPO is
activated and sleep is switched on.
There is similar switch between REM and Non-
REM sleep mediated by mutually inhibiting
REM on and REM off neurons.
REFERENCE: 1)Guyton Textbook Of Medical
Physiology
2)YouTube Videos