Sleep is a naturally recurring state that involves altered consciousness, inhibited sensory activity, and reduced muscle activity. It is important for healing, repairing the body, and improving concentration. There are four stages of sleep: three non-REM stages and one REM stage. The hypothalamus influences sleep cycles by regulating the release of melatonin in response to light, which makes people feel sleepy. Factors like age, recent sleep patterns, and sleep disorders can affect normal sleep stage progression.

1. Ammarah Saleem
Lecturer
Department of Applied Psychology, GCWUF
SLEEP MOTIVATION

2. What is sleep?
• Sleep is a naturally recurring state of mind and body.
CHARACTERISTICS:
1. altered consciousness
2. relatively inhibited sensory activity
3. reduced muscle activity
4. inhibition of nearly all voluntary muscles during rapid eye
movement (REM) sleep
5. reduced interactions with surroundings.
6. Brain’s overall activity is not reduced
During certain stages of sleep, O2 uptake by the brain is even
increased above normal waking levels

3. How much sleep do we
need?
1. Infants generally require about 16 hours a day
2. teenagers need about 9 hours on average.
3. For most adults, 7 to 8 hours a night appears to be the
best amount of sleep
4. Women in the first 3 months of pregnancy often need
several more hours of sleep than usual.

4. Why is sleep important?
1. Sleep plays an important role in:
2. Healing and repair of your heart and blood vessels.
3. Decreased risk of heart disease, kidney disease, high
blood pressure, diabetes, and stroke.
4. Improve concentration and productivity.

6. Stages of sleep
There are four sleep stages one for rapid eye movement
(REM) sleep and three for non-REM (NREM) sleep.
These stages are determined based on an analysis of brain
activity during sleep, which shows distinct patterns that
characterize each stage.

8. Comparison of REM sleep and
NON-REM
sleep
Characteristic REM sleep Non-REM sleep
Rapid eye movement Present Absent
Dreams Present Absent
Muscle twitching Present Absent
Heart rate Fluctuating Stable
Blood pressure Fluctuating Stable
Respiration Fluctuating Stable
Body temperature Fluctuating Stable
neurotansmitter Noradrenaline serotonin

9. Role of Hypothalamus
• The release of melatonin is influenced by a structure deep
within the tiny hypothalamus in an area called
the suprachiasmatic (SOO-prah-ki-AS-ma-tik) nucleus, the
internal clock that tells people when to wake up and when to
fall asleep.
• The nucleus of the suprachiasmatic, or SCN, is sensitive to
light changes.
• The SCN tells the pineal gland (located in the brain’s base) to
secrete melatonin as daylight fades.
• A person will feel sleepy as melatonin accumulates.
• The SCN tells the pineal gland to stop secreting melatonin as
the light coming into the eyes increases (as it does in the
morning), enabling the body to awaken. For such a small part

10. Theories of sleep

11. What Affects Sleep Stages?
Age: New-borns spend far more time (around 50%) in REM
sleep and may enter a REM stage as soon as they fall asleep. As
they get older, their sleep becomes similar to that of adults.
Recent sleep patterns: If a person gets irregular or insufficient
sleep over a period of days or more, it can cause an abnormal
sleep cycle.
Sleep disorders: Sleep apnea, Restless leg syndrome (RLS),
and other conditions that cause multiple awakenings may
interrupt a healthy sleep cycle.