The sleep cycle is controlled by centers in the lower brain and follows a circadian rhythm of about a day. Sleep involves non-REM and REM stages in cycles lasting around 90 minutes each night. During sleep, vital signs like blood pressure and heart rate decrease while growth hormones increase. Inadequate sleep can cause irritability and difficulty concentrating. Sleep disorders can be primary, caused by issues like insomnia or sleep apnea, or secondary due to illnesses, stress, medications and other lifestyle factors. Polysomnography tests are used to diagnose sleep issues.

1. SUPRIYA PATKAR

4.  The cyclic nature of sleep is thought to be
controlled by centers located in the lower part
of the brain.

5.  Circadian- Latin word- Circa dies- about a
day
 When a person’s biologic clock coincides with
sleepwake pattern, the person is said to be in
circadian synchronization.

6.  NON RAPID EYE MOVEMENT (NREM)
 RAPID EYE MOVEMENT (REM)
EEG provides a good picture of what occurs
during sleep.

7.  Also referred as slow wave sleep.
 Brain waves of a sleeper are slower than the
Alpha & Beta waves compare to awake
person.
 Most of night sleep is NREM sleep.

8.  Arterial blood pressure falls.
 Pulse rate decreases.
 Peripheral blood vessels dilate.
 Cardiac output decreases.
 Skeletal muscle relax.
 BMR decreases.
 Growth hormones levels peak.
 ICP decreases.

9.  Stage I
 Stage II
 Stage III
 Stage IV

10.  Occurs every 90 minutes & lasts 5 to 30
minutes.
 Dreams takes place.
 Brain is highly active.
 Brain metabolism increases.

11.  Sleeper may be difficult to arouse or may
awake spontaneously.
 Muscle tone is decreased.
 Gastric secretions increase.
 Heart & respiratory rate are irregular.

12. 7-8
hrs(4-6
cycles)
Stage
I,II,III (20-
30 min)
Stage IV
Stage III,
II (20 min)
I REM
stage
10min

13.  Sleep exerts physiologic effects on both the
nervous system & other body structures.
 Sleep in some way restores normal levels of
activity & normal balance among parts of the
nervous system.
 Sleep is also necessary for protein synthesis
which allows repair process to occur.
 The role of sleep in deterioration in mental
functioning related to sleep loss.
 Persons with inadequate amounts of sleep tend
to become emotionally irritable, have poor
concentration & experience difficulty making
decisions.

14.  Illness
 Environment
 Fatigue
 Lifestyle
 Emotional stress
 Stimulants & alcohol
 Diet
 Smoking
 Motivation
 Medication

15.  Parasomnias – behavior that may interfere
with sleep or that occurs during sleep.
Types
 Arousal disorders
 Sleepwake transition disorder
 Parasomnias associated with REM sleep
 Others

16.  Primary sleep disorders – are those in which
the person’s sleep problem is the main
disorder.
Types
 Insomnia
 Hypersomnia
 Norcolepsy
 Sleep apnea
 Sleep deprivation

18.  EEG
 EMG
 ECG
 Spo2
 Physical examination
 Sleep diary