แพทย์หญิง กาญจนา พิทกั ษ์วฒ
ั นานนท์
อายุรแพทย์ผเู้ ชีย่ วชาญระบบประสาท
แพทย์ประจาศูนย์สมอง โรงพยาบาลสมิตเิ วชศรีราชา
 Brain
development
 Memory
/ cognition / long term potential
 Immunity
 Conservation
 Repair
energy
& Restoration
 Regular
sleep time
 Proper sleep environment
 Stimulation control
 Avoidance of time in bed worrying
 Avoidance of poorly timed alcohol and
caffeine
 Regular exercise but not within 3 hours of
bedtime
 Wind-down time
 Late-night high-tryptophan snack
 Human
circadian clock generates a
rhythm slightly longer than 24 hours
when it has no external cue to set it.
 Most people can adjust to 23- or 25hour day but not to a 22- or 28- hour
day.
 Bright light late in the day can
lengthen the circadian rhythm.
Duration of sleep
•Circadian rhythm
•Circadian clock
•Zeitgeber
•Circannual rhythm




The purpose of the
circadian rhythm is to keep
our internal workings in
phase with the outside
world.
Light is critical for
periodically resetting our
circadian rhythms.
A zeitgeber is a term used
to describe any stimulus
that resets the circadian
rhythms.
Exercise, noise, meals, and
temperature are others
zeitgebers.

Mechanisms of
the circadian
rhythms include
the following:
• The
Suprachiasmatic
nucleus.
• Genes that
produce certain
proteins.
• Melatonin levels.
Physiological pathway of the biological clock:
Light levels  retina
 suprachiasmatic nucleus of hypothalamus
 pineal gland  secretion of melatonin
suprachiasmatic nucleus
The
(SCN) is
part of the hypothalamus and the main control center of the
circadian rhythms of sleep and temperature.
0.15-0.3 Hz
4.5-6.5 Hz
4-8 Hz
5.0-10.0 Hz
5.8 Hz
7 Hz
8.6-9.8 Hz
15.0-18.0 Hz
18 Hz
55 Hz
- depression
- wakeful dreaming, vivid images
- dreaming sleep,
deep meditation,
subconscious mind
- relaxation
- dizziness
- increased reaction time
- induces sleep, tingling sensations
- increased mental ability
- significant improvements in memory
- Tantric yoga
 Meditation
= practices that train attention
to heighten awareness and bring mental
processes under greater voluntary control
 Yoga,
Zen, transcendental meditation
(TM)
• Potential physiological benefits
 Similar to effective relaxation procedures
 EEG
( electro-encephalography )
 EOG ( electro-oculograms )
 Chin EMG ( electro-myograms )

Left & Right anterior tibialis EMG
Intercostal EMG

ECG ( electro-cardiogram )




Pulse oximetry ( oxygen saturation )
Nasal & Oral thermistors ( airflow )
Chest & Abdominal strain guages
EEG:
- rhythmic alpha waves (8-12Hz) // only if the eyes are closed
- beta waves (20-30Hz)
EOG:
- eye movement (observation process)
EMG:
- continual tonically activity of muscles
 Loss
of eye blink
 Attenuation
 Slow
of Alpha rhythm
rolling eye movements
 Fronto
central Theta activity
 Increased
 Vertex
Beta activity
waves
EEG:
- the absence of alpha activity
- Vertex sharp waves
EOG:
- slow eye movement
EMG:
- relatively lower amplitude

Sleep spindles
• Brief , 12 – 16 Hz , synchronous bursts of activity , usually
maximal in the central , or less commonly frontal , regions

K complexes
• Often accompany sleep spindles . A sharp negative wave
followed by a high-voltage slower wave

Vertex waves
• Named for tendency to phase reverse in central regions.
• Sharp waves
• May occur in trains

K complexs & Vertex waves may result from brief
sleep disturbances
EEG:
- sleep spindles (oscillating with the frequency between 12-15 Hz)
- K-complexes (high voltage, sharp rising and sharp falling wave)
- relatively low voltage mixed frequency
EOG:
- the absence eye movements
EMG:
- constant tonic activity

> 20 % but < 50 % of the background
rhythm is Delta activity
EEG:
- consists of high-voltage (>=75uV)
- slow delta activity (<=2 Hz) // electrodes Fpz-Cz or Pz-Oz
EOG:
- the absence eye movement
- delta waves from EEG
EMG:
- low tonic activities

> 50% of the background rhythm is
Delta activity
 Bursts
of rapid eye movement
 Loss of muscle activity
 “ Desynchronization ” of the background
rhythm.
• The predominant delta rhythm of slow wave (
stage III & IV ) sleep is replaced by faster
frequency ( beta and theta ) rhythms normally
seen during the wakeful state.
 Sawtooth
waves
EEG:
- relatively low voltage
- mixed frequency
EOG:
- contains rapid eye movements
EMG:
- tonically suppressed (Sleep Paralysis)

Insomnia – difficulty falling or staying asleep

Narcolepsy – falling asleep uncontrollably

Sleep Apnea – reflexive gasping for air that awakens

Nightmares – anxiety arousing dreams – REM

Night Terrors – intense arousal and panic – NREM

Somnambulism – sleepwalking