The homeostatic process (S) and circadian process (C) interact to regulate the sleep-wake cycle. Process S represents the buildup of sleep pressure and increasing need for sleep with time spent awake. Process C is controlled by the suprachiasmatic nucleus and follows a 24 hour circadian rhythm promoting wakefulness during the day and sleep at night. When the distance between processes S and C is largest, sleep propensity is highest. Together these two processes maintain optimal times for sleep, wakefulness, and transitions between states.

3. ‫النوم‬...‫هللا‬ ‫آيات‬‫من‬ ‫آية‬!

5. Sleep wake regulation

9. Sleep wake regulation

10. Sleep is not a passive process

11. When we are awake, specific areas within the brainstem and within a region of the brain
called the hypothalamus send signals that stimulate the cerebral cortex. By keeping
neurons in the cortex active, signals from these arousal centers maintain
consciousness and allow for complex brain functions, such as memory and speech, to

12. The ascending reticular activation system. During periods of wakefulness, impulses from
the brainstem activate neurons in the thalamus that are crucial for transmitting
information to the cerebral cortex. Impulses also travel to the hypothalamus and
throughout the cerebral cortex. A key switch in the hypothalamus (SCN, or
suprachiasmic nucleus) that serves as the brain's 'master clock' shuts off this arousal

13. Neurons in an area of the brain called the ventrolateral preoptic area (VLPO) help to
promote sleep by inhibiting activity in areas of the brain that maintain wakefulness.
Neurotransmitters released from VLPO neurons reduce activity in the arousal regions,
causing us to pass quickly into the unconscious state of NREM sleep.

14. Sleep/Waking “Flip-Flop”
vlPOA= ventrolateral preoptic area
ACh = acetylcholine
NE = norepinephrine
5-HT = serotonin

15. 15
The Sleep/Waking Flip-Flop. According to Saper et al. (2001), the major sleep-promoting
region (the vlPOA) and the major wakefulness-promoting regions (basal forebrain and
pontine regions that contain acetylcholinergic neurons; the locus coeruleus, which
contains noradrenergic neurons; the raphe nuclei, which contain serotonergic neurons;
and the tuberomammillary nucleus of the hypothalamus, which contains histaminergic
neurons) are reciprocally connected by inhibitory GABAergic neurons. (a) When the flip-
flop is in the “wake” state, the arousal systems are active and the vlPOA is inhibited, and
the animal is awake. (b) When the flip-flop is in the “sleep” state, the vlPOA is
active and the arousal systems are inhibited, and the animal is asleep.

16. Sleep/Waking Flip-Flop

17. Sleep/Waking Flip-Flop

18. Brain Regions That Control Sleep
and Arousal
• The arousal-promoting nuclei (LC, Raphe, and
TMN) make broad, diffuse connections to the entire
cerebral cortex.
• The neurotransmitters released (norepinephrine,
serotonin, and histamine) work to promote
wakefulness by setting a level of activity in the
cerebral cortex. These regions are
sometimes referred to as the Reticular activating
system.

19. Brain Regions That Control Sleep
and Arousal
• Some of the arousal-promoting nuclei also have an
inhibitory connection to the VLPO.
• The sleep-promoting nucleus (VLPO) releases
GABA, the major inhibitory neurotransmitter in the
brain.
• VLPO makes direct inhibitory connections to all of
the arousal-promoting nuclei, promoting sleep and
turning off arousal systems during non-REM sleep.

20. Brain Regions That Control Sleep
and Arousal
• Note that there is mutual inhibition between the
sleep-promoting and arousal-promoting nuclei. This
creates a system in which transitions from one state
to another are full, rapid and efficient. For example,
a small change that promotes wakefulness, will
cause inhibition of VLPO, and thus reinforce a
transition to waking through removal of the VLPO
inhibition on arousal-promoting nuclei.

25. 25
Sleep is Regulated by a two Process
System
1. Sleep/Wake
Restorative
Process “S”
Balances Sleep and
Wakefulness
2. Circadian
Biological
Clock “C”
Regulates Timing of
Sleep and
Wakefulness (SCN)
Borbely AA. Hum Neurobio -1982

27. • Two modular processes that govern sleep and
wakefulness
• Referred to as “two process model” of sleep wake
regulation
1. Homeostatic drive for sleep
2. Intrinsic circadian rhythm
• For each hour of wakefulness, homeostatic drive
for sleep increases
– Typically after 14-16 hours, sufficient
homeostatic sleep drive is obtained

28. Human homeostasis
• Is derived from the Greek, homeo or "same", and
stasis or "stable" and means remaining stable or
remaining the same.
• The human body manages a multitude of highly
complex interactions to maintain balance or return
systems to functioning within a normal range.
These interactions within the body facilitate
compensatory changes supportive of physical and
psychological functioning. This process is essential
to the survival of the person and to our species

29. Homeostasis
• Maintenance of equilibrium by active regulation
of internal states:
• Cardiovascular function (blood pressure, heart
rate)
• Body temperature
• Food and energy regulation
• Fluid regulation
High level (hyper-)
Low level (hypo-)
Correct level (set point)
Sens
or
EffectorBrain
Change
Feedback

30. Summary of homeostatic control
• Multiple mechanisms control homeostasis
• Emphasises the importance to survival
• Set points are not fixed
– Many homeostatic functions show daily rhythms
– Maintain levels appropriate for the level of
activity
– Therefore efficient in energy use.Example
• During sleep body temperature decreases
• Heart rate decreases
• Respiration rate decreases
 Energy conservation

31. Sleep Drive
• Scientists refer to sleep drive as a homeostatic
system. Like body temperature or blood sugar,
sleep is regulated internally.
• For instance, when body temperature falls, blood
vessels constrict and we shiver; when blood sugar
levels rise, the pancreas secretes insulin; and
when we remain awake for an extended period of
time, structures in the brain promote sleep.

32. Sleep Drive
• During waking hours, the sleep drive gradually
increases until it reaches a critical threshold
• With every waking hour there is a strengthening of
the homeostatic sleep drive.
• Furthermore, the duration and depth of our sleep
vary according to the quantity and quality of sleep
obtained previously ( Sleep wake history ).

33. •Homeostatic regulation of sleep :
The pressure to sleep grows stronger across the day as one stays
awake and then dissipates when one sleeps at night (shaded area).
•Sleep pressure increases (dashed line) as one stays awake longer
into the normal sleeping hours.

34. Circadian rhythm
Refers to circa=approximately and
dias=day

38. • Both animal and human studies support a model
of 2 processes that regulate sleep and
wakefulness: homeostatic and circadian.
• The homeostatic process is the drive to sleep that
is influenced by the duration of wakefulness.
• The circadian process transmits stimulatory
signals to arousal networks to promote
wakefulness in opposition to the homeostatic drive
to sleep
Sleep-wake regulation

39. • Natural sleep cycle consists of being
awake during the day and asleep at
night.
National Sleep Foundation

41. Light information
transmitted to the brain
by non-visual neurons
originating in the back
of the eye

42. Retinohypothalamic pathway

43. - Exposure to light stimulates a nerve pathway in the
retina (eye) to a special center in the brain (supra-
chiasmatic nucleus, SCN)
- SCN regulates a pattern of activities that affect our
whole body. It releases cortisol, a stimulating hormone
that prompts our body to do many activities.
- It also releases another hormone, melatonin, in the
body. Melatonin is released by the pineal gland when
darkness occurs. Melatonin stays level in the blood
for about 12 hours (all through the night).
- When daytime arrives the pineal gland shuts down
and the level of melatonin is barely detectable in the
blood during during the day.

44. The SCN is the body’s master clock. The suprachiasmatic nucleus (SCN) is a small
group of brain cells located in the hypothalamus that controls the circadian cycles
and influences many physiological and behavioral rhythms occurring over a
24-hour period, including the sleep/ wake cycle.

45. The Suprachiasmatic Nucleus

46. Circadian Rhythms
Suprachiasmatic Nuclei
(SCN)
Light Output Rhythms
Physiology
Behavior

47. How do biological rhythms differ?
• Circadian rhythms – 24 hours (daily cycle)
(e.g. sleep–waking cycle/body temperature/HR )
• Infradian – more than one day (e.g. Menstruation
/hibernation/SAD)
• Ultradian – more than one cycle in 24 hours (e.g.
the cycles of night-time sleep)
• Circannual rhythms (yearly cycle)
Hibernation, mating behaviour, migration

48. Biological Rhythms
• Many of our behaviors display rhythmic variation
– SWS/REM cycles last about 90 minutes
– Circadian rhythms (“about a day”)
• One cycle lasts about 24 hours (e.g. sleep-waking cycle)
• Light is an external cue that can set the circadian rhythm
• Some circadian rhythms are endogenous (do not require
light) suggesting the existence of an internal (biological)
clock
– Monthly rhythms
• Menstrual cycle
– Seasonal rhythms
• Aggression, sexual activity in male deer
• Hibernation

49. ©John Wiley & Sons, Inc. 2007
Huffman: Psychology in Action (8e)
Circadian Rhythms
• Circadian Rhythms (biological changes occurring
on a 24-hour cycle)
– Our energy level, mood, learning, and alertness
all vary throughout the day.
– Sections of the hypothalamus called the
suprachiasmatic nucleus (SCN) and the pineal
gland regulate these changes.

51. • Circadian rhythm, is a signal generated by the
master clock in the human brain, the
suprachiasmatic nucleus (SCN) located in the
anterior hypothalamus.
• Circadian rhythm, derived from the Latin term “circa
diem”, which literally means “approximately one day”
is the body’s internal clock. This clock is set at
slightly over 24 hours.
• It controls sleep as well as most biological
processes, including hormone production,
metabolism, core body temperature variations and
cell regeneration among others.
• This clock is normally highly synchronized to
environmental cues, or zeitgebers (German for “time
giver”), the strongest of them being the light-dark

52. • The body’s biological clock controls most circadian
rhythms. This clock is known medically as the SCN,
or suprachiasmatic nucleus, and is located in the
brain in the hypothalamus.
• The SCN receives signals through the eyes. Signals
from the SCN are then transported to different areas
of the brain, such as the pineal gland. This gland
responds to light-inducing signals and regulates the
production of the melatonin hormone. When it’s
dark, the level of melatonin in our body increases,
which in turn makes people feel sleepy.

53. • The circadian rhythm can be reset by bright lights
or sunlight, and therefore our biological cycles,
rather than our innate cycle, follow the cycle of the
sun.
• To a certain degree, circadian rhythms are also
affected by external time cues such as the ringing
of an alarm clock, meal timings, a bed-time ritual
etc.

54. Circadian Rhythms
• Sleep is periodic--it is required, on average, about
every day
• Humans, like all mammals, have a 24 hour
biological clock
• If people are placed in an environment without any
access to daylight, clocks, etc, they follow an
activity/rest cycle of about 24.5 hours

55. Circadian Rhythm Biology
• Circadian rhythms generated from
superchiasmatic nucleus (SCN) of hypothalamus
• In the 1970s, studies in rats identified the
suprachiasmatic nucleus as the location of the
internal clock.
• Signals from SCN modulate daily rhythms in sleep
and alertness
– Core body temperature
– Secretion of cortisol and melatonin
• Linked to: Light/dark cycle

56. • Circadian rhythm:
– rhythm or cycle that is about a day in length.
– Circa = about = approx
– Dia = day
• Suprachiasmatic nucleus (SCN) of the hypothalamus:
– Main brain area that functions as biological clock
– Controls circadian rhythms in mammals
1. Sleep and activity,
2. Body temperature,
3. Drinking
4. Steroid secretion.
5. Functions as pacemaker: keeps time and regulates
activity of other cells

57. 57
• By endogenous pacemakers – innate, internal
body clocks – such as the suprachiasmatic
nucleus (SCN).
• By exogenous zeitgebers – external,
environmental stimuli – such as light,
temperature and food availability.
• These work together to regulate biological
rhythms.
• Absolutely independent from the duration of
How are biological rhythms controlled?

58. 58
o The sleep–waking cycle (24 hours) is the central
circadian rhythm in humans – it synchronises
other bodily processes.
o The SCN (a body clock) is responsive to light.
o Light is converted to nerve impulses at the retina.
o These impulses stimulate the SCN which works
to a circadian rhythm.
o With the pineal gland the SCN synchronises
biological rhythms

59. The pineal gland
– Linked to the SCN – it makes melatonin,
which has widespread effects on the brain
and on the body’s physiological systems.
– Light reduces melatonin activity in the brain
and so controls the sleep–waking cycle.
– The SCN and pineal gland are
synchronised with lightness and darkness
in the outside world.

60. • The SCN regulates pineal gland’s secretion of
melatonin
– Light resets biological clock by suppressing
melatonin secretion
– Melatonin = hormone that induces sleepiness.
• Light information reaches SCN via direct
connection from retinas: retinohypothalamic
pathway.

62. 62
Circadian Biological Clock (Process “C”)
o SCN – located in the anterior hypothalamus
o Process “C” is affected by light and external cues

63. • The Circadian Biological Clock that regulates our
24-hour sleep-wake cycle resides in and is
controlled by a group of cells in our hypothalamus
called the Suprachiasmatic Nucleus or SCN.
• From the optic nerve of the eye, light travels to the
SCN, signaling the clock that it is light and daytime.
• When it is dark, we are driven to sleep and when it
is light, we are alert.
• This clock knows “what time it is” by being
synchronized with the eye’s exposure to light

65. Homeostatic and circadian regulation of human
sleep Borbely et al., 2001
Time of Day
Sleep
propensity
Sleep
propensity
High
High
Low
Low

66. Sleep-wake regulation
Borbély’s model of sleep-wake regulation (Borbély & Achermann, 1999).
Process S represents the homeostatic built-up of sleep pressure.
Process C represents the circadian rhythm.
When the distance between process S and process C is largest, sleep propensity will be

67. • The homeostatic process (S) is pretty
straightforward, the longer you are awake the higher
the sleep pressure will become, while sleep will
result in a reduction of sleep pressure and the
propensity to wakefulness.
• It however doesn’t mean that the higher the sleep
pressure as expressed by the homeostatic process
it’s easy to fall asleep. That is because there is
another process that regulates the tendency to fall
asleep, i.e. the Circadian rhythm.

68. • The circadian rhythm (C) is a rhythm that
fluctuates with a cycle of about 24 hours (hence
the name “circadian”).
• This rhythm (or oscillation) is driven by a so-called
pacemaker, the suprachiasmatic nucleus, that is
regulated by the light-dark cycle.

69. • The suprachiasmatic nucleus receives light input
from the retina in the morning, by which the
circadian clock is reset.
• circadian clock or pacemaker synchronizes different
physiological rhythms, e.g. body temperature,
melatonin secretion, cortisol secretion…
• So the light-dark cycle helps synchronize the
homeostatic rhythm and circadian clock, with low
sleep pressure corresponding to a circadian process
that promotes wakefulness.

70. Sleep-wake regulation
The bigger the distance between process S and process C, the
higher the sleep pressure. So that’s the moment when sleep will
normally be initiated.

72. Sleep
zone
Awake
zone

73. Sleep Academic Award 73
The opponent process model

74. © American Academy of Sleep Medicine
American Academy of Sleep Medicine
Interaction of Circadian Rhythms and Sleep
Time
9 PM9 AM 9 AM
SleepWake
Sleep Homeostatic
drive (Sleep Load)
Circadian alerting signal
Alertness level
3 PM 3 AM

75. • Internal "body clock" , which gradually becomes
established during the first months of life, controls
the daily ups and downs of biological patterns,
including body temperature, blood pressure, and
the release of hormones.
• The circadian rhythm makes people’s desire for
sleep strongest between midnight and dawn, and
to a lesser extent in midafternoon.

77. • In most humans the sleep pattern shows a
biphasic distribution, with a mid-day decrease in
alertness around 2-4 pm, followed by an increased
alertness during mid to late evening, and finally
declining to its lowest levels during the night.
• In societies where taking a siesta is the norm,
people can respond to their bodies’ daily dips in
alertness with a one- to two-hour afternoon nap
during the workday and a correspondingly shorter
sleep at night.
Napping and Culture

78. Development of sleep patterns. Short cycles of sleep and waking
gradually become the night-day cycle of an adult. While most adults don’t
take naps, midafternoon sleepiness is a natural part of the sleep cycles.
(After Williams et al., 1964.)

79. •‫شرع‬ ‫مستحبة‬ ‫القيلولة‬‫نومة‬‫ا‬‫ا‬‫عن‬ ‫وي‬ُ‫ر‬ ‫فقد‬‫لن‬‫بى‬
(‫آله‬‫و‬ ‫عليه‬ ‫هللا‬ ‫ى‬َّ‫ل‬‫ص‬)‫ال‬‫ق‬ ‫أنه‬:"ُ‫ن‬َ‫او‬َ‫ع‬َ‫ت‬ِ‫ر‬‫و‬ُ‫ح‬َّ‫الس‬ ِ‫ل‬ْ‫ك‬َ‫أ‬ِ‫ب‬ ‫وا‬
ِ‫م‬‫ا‬َ‫ي‬ِ‫ص‬ ‫ى‬َ‫ل‬َ‫ع‬“َ‫ق‬ْ‫ل‬‫ا‬َ‫د‬ْ‫ن‬ِ‫ع‬ ِ‫م‬ْ‫و‬َّ‫ن‬‫ال‬ِ‫ب‬ ‫و‬ ِ‫ر‬‫ا‬َ‫ه‬َّ‫ن‬‫ال‬‫ة‬َ‫ل‬‫و‬ُ‫ل‬ْ‫ي‬‫الليل‬‫قيام‬ ‫على‬
•‫غف‬ ‫نأخذ‬ ‫أن‬‫وسلم‬ ‫عليه‬ ‫هللا‬ ‫صلى‬ ‫هللا‬ ‫رسول‬ ‫أمرنا‬‫خالل‬‫وة‬
‫النهار‬
‫ال‬‫فق‬:(‫تقيل‬ ‫ال‬ ‫الشياطين‬‫إن‬‫ف‬ ،‫قيلوا‬)‫الطب‬‫رواه‬‫راني‬

80. ‫الحديث‬ ‫في‬" :‫تقيل‬ ‫ال‬ ‫الشياطين‬ ‫فإن‬ ‫قيلوا‬"،
‫من‬ ‫هي‬ ‫للقيلولة‬ ‫المناسبة‬ ‫المدة‬ ‫أن‬ ‫تؤكد‬ ‫الدراسات‬ ‫أغلب‬15
‫إلى‬20‫الساعة‬ ‫بين‬ ‫ما‬ ‫هو‬ ‫لها‬ ‫األفضل‬ ‫التوقيت‬ ‫وأن‬ ،‫دقيقة‬
‫التي‬ ‫الفترة‬ ‫وهي‬ ،‫الزوال‬ ‫بعد‬ ‫الثالثة‬ ‫والساعة‬ ‫الواحدة‬
‫كذلك‬ ‫وهي‬ ،‫لإلنسان‬ ‫والجسمي‬ ‫الفكري‬ ‫النشاط‬ ‫فيها‬ ‫ينخفض‬
‫الفت‬ ‫بعد‬ ،‫الخطيرة‬ ‫السير‬ ‫حوادث‬ ‫أغلب‬ ‫فيها‬ ‫تقع‬ ‫فترة‬ ‫ثاني‬‫رة‬
‫الليلية‬

81. SleepAdapted from Edgar DM et al. J Neurosci. 1993;13:1065-1079.
Wake
Sleep
Sleep Load
Circadian
Alerting Signal
9am 3pm 9pm 3am 9am
Regulation of Sleep and Wake
Circadian and Homeostatic Processes
Wake
Propensity
Melatonin
Wake propensity
Circadian
alerting
signal

86. • Sleep homeostatic drive (sleep load) builds up during
wake, reaching a maximum in the late evening (near
usual sleep time).
• The circadian system facilitates awakening and
through the day usually acts as a counterbalance to
the progressive accumulation of sleep load.
• The relative level of sleepiness or alertness existing at
any given time during a 24-hour period is determined
by the duration and quality of previous sleep, as well
as time awake since the last sleep period, interacting
with the 24 hour cyclic pattern or rhythm
characterized by clock-dependent periods of maximum
sleepiness and maximum alertness .

87. 2-Process Model of Sleep/Wake Regulation
1 Sleep homeostasis or
internal drive, exact
mechanism unknown
• Pressure to sleep
increases throughout the
day until an internal
threshold is crossed
causing sleep to occur
• Waking occurs when
homeostatic drive
decreases sufficiently to
cross opposite threshold
2 Circadian rhythms
• Refers to cyclical
changes that occur over
a 24 hour period driven
by an internal “biological
clock” located in the
brain in the
suprachiasmatic nucleus
(SCN)
• Synchronized to external
physical environment

88. • Human sleep is believed to be regulated by three
basic neural processes:
1. Homeostatic process, whose magnitude depends on
the amount of prior sleep and wakefulness,
2. Circadian process, which is governed by an
endogenous circadian pacemaker generating near
24-hour cycles of behavior
3. Arousal network, which promotes wakefulness and
opposes the drive for sleep.
• It is hypothesized that the interaction between
homeostatic, circadian, and arousal systems is
responsible for helping humans to maintain
wakefulness during the day and consolidated sleep at

90. SLEEP HORMONE
• After a series of research on SLEEP, Scientists
revealed that, there is a hormone which regulates
sleep and awake cycle. The hormone is
MELATONIN.
• It is a hormone secreted by pineal gland. This
hormone is secreted on the basis of our body clock.
The amount of secretion of melatonin varies, it
depends on age, time, sex and also the place where
a person is living.We can clearly say the sleep is
due to the effect of action of melatonin.

91. Melatonin and the Circadian process
• The suprachiasmatic nucleus (SCN) is entrained to the
external environment by the cycle of light and
darkness.
• The retinal ganglion cells transmit light signals via the
retinohypothalamic tract to stimulate the SCN.
• A multisynaptic pathway from the SCN projects to the
pineal gland, which produces melatonin.
• Melatonin synthesis is inhibited by light and stimulated
by darkness. The nocturnal rise in melatonin begins
between 8 and 10 pm and peaks between 2 and 4
am, then declines gradually over the morning.

92. Melatonin Secretion
Time of Day
MelatoninLevel
7 am 7 pm 7 am
asleep
www.psychlotron.org.uk

93. LIGHT
EXERCISE
FOOD, SOCIAL
EYE
Master clock:
Suprachiasmatic
nucleus
“Zeitgebers”
(time givers)
“entrain” clock
Anterior
hypothalamus

94. LIGHT
EXERCISE
FOOD, SOCIAL
EYE
Master clock:
Suprachiasmatic
nucleus
“Zeitgebers”
(time givers)
“entrain” clock
Pineal
Gland
Regulates:
Hormones
Sleep/wake
Temp

95. No LIGHT
EYE
Master clock:
Suprachiasmatic
nucleus
Pineal
Gland
Melatonin “phase
marker”
Sleep
(night)
AM
Regulates: -
Hormones -
Sleep/wake -
Temp

96. LIGHT
EXERCISE
FOOD, SOCIAL
EYE
Master clock:
Suprachiasmatic
nucleus
“Zeitgebers”
(time givers)
“entrain” clock
Pineal
Gland
No Melatonin
Wake
(day)
PM
Regulates: -
Hormones -
Sleep/wake -
Temp

98. • Melatonin is secreted maximally during the night
by the pineal gland.
• Prolactin, testosterone, and growth hormone also
demonstrate circadian rhythms, with maximal
secretion during the nigh.
• Many other physiologic functions such as hormone
secretion, urine production, and changes in blood
pressure are under circadian control and
synchronized with the sleep/wake cycle.

101. Melatonin Secretion
• Increase in levels
around 8:00pm
• Levels peak at
approximately
3:00am and begin
to decrease
• Lowest levels just
before awakening

102. Melatonin
• A hormone secreted by the pineal gland
– contains light-sensitive cells or has nervous
connection from the eyes
– converts serotonin into melatonin
• The Melatonin/Serotonin cycle
Tryptopha
nMelatonin
Serotonin
neurotransmitter of the
sleeping-producing
high in milk

103. The mechanism through which light inhibits melatonin secretion by the pineal
gland involving the neural pathway originating in the retina and passing through
the suprachiasmatic nucleus in the brain, to reach pinealocytes via adrenergic
nerves and adrenergic receptors, and subsequently to the periphery
Koch, B. C. P. et al. (2009) Circadian sleep–wake rhythm disturbances in end-stage renal disease
Nat Rev Nephrol doi:10.1038/nrneph.2009.88

104. Regulation of the melatonin secretion
SCN (suprachiasmatic nucleus)
Melatonin
project the information
about illumination
Ganglion cells
Pineal gland
interprets the information on the
lengths of the day and night
secretes
feedback:
decrease the
activity of SCN

105. • Being set in the middle of our brains, the pineal
gland has no direct access to sunlight. Our eyes
send it a message of how much sunlight they see,
and when it¹s dark.
• The sunlight prohibits the gland from producing
melatonin, so at night, when there¹s no sun, the
sleep-inducing hormone is released into our bodies.
• Because of the pineal gland and melatonin, humans
have known to sleep at night and wake during the
day since long before the age of alarm clocks.

106. Melatonin and the Pineal Gland

107. • Melatonin is known as the regulator of regulators,
because it sends out the messages that control
the amounts of all the different hormones in our
bodies.
• It is a balance among our different hormones that
keeps us healthy, and as we age, our different
hormone levels can become unbalanced, which
results in aging.

108. • a vital part of many biochemical systems
– including sleep and learning
• Free radical scavenging in all cells
– a potent Antioxidant with anti-aging and anti-
cancer properties
• Helps to protect embryonic fetuses
• Mediates many hormone functions
• Assists in maintaining immune system health and
virus protection
Functions of melatonin

111. • Humans don¹t produce melatonin right from birth; it
is transferred in utero to babies through the
placenta. For their first few days of life, babies still
have to receive it from breast milk.
• Our levels of melatonin peak during childhood, and
then decrease at the beginning of puberty, so that
other hormones can take control of our bodies.
• As we get older, the amount of melatonin we
produce continues to decrease until at age 60, we
produce about half as much as we did at age 20.

114. Melatonin and the Pineal Gland

115. HGH and Sleep
• Growth hormone is normally released during the most
restful phase of slow wave sleep (SWS).
• Growth hormone plays a vital role in human health,
stimulating bone growth, immune function, amino acid
uptake, protein synthesis, and muscle glucose uptake.
Growth hormone also induces the burning of fat from
adipose tissues and plays a key role in maintaining
cardiovascular health.
• Reduction of growth hormone in aging humans is
associated with immune system malfunctions,
increased body fat deposits, a loss of muscle tone and
overall physical strength, thinning of skin, and
diminished sexual drive.

116. HGH and Sleep
• Bulk of your HGH is produced and secreted in deep
sleep, especially in the first two hours of sleep. This is
the reason why fat is burned when you sleep and not
during exercise.
• That's right ... fat is burned when you sleep.
• In fact, sleep deprivation and weight gain are
interconnected. So much so that with a client I will
usually have them first start with a sleep diet before
anything else!
• Professional weightlifters and bodybuilders all make

120. Light Pollution

121. Light Pollution

122. Light Pollution

123. Light Pollution is Uplight

124. Light Pollution is Uplight

125. Light Trespassing from East Hampton IGA to residential properties

126. Sleep Duration Time Trends in US Adults
9.0
7.5
6.8
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.0
1910 1975 2005
Hrs per night
National Sleep Foundation. Sleep in America Poll

127. Sleep duration in British Adults
(1967/2003)
Groeger JA et al. J Sleep Res. 2004; 13:359-71
1967
2003

128. ِ‫ه‬ْ‫ي‬َ‫ل‬َ‫ع‬َُّ‫اَّلل‬‫ى‬َّ‫ل‬َ‫ص‬ َِّ‫اَّلل‬ُ‫ول‬ُ‫س‬َ‫ر‬َ‫ال‬َ‫ق‬َ‫م‬َّ‫ل‬َ‫س‬َ‫و‬(ِ‫ب‬‫ا‬َ‫ص‬َ‫م‬ْ‫ل‬‫ا‬‫وا‬ُ‫ئ‬ِ‫ف‬ْ‫ط‬َ‫أ‬َ‫يح‬
ْ‫م‬ُ‫ت‬ْ‫د‬َ‫ق‬َ‫ر‬ ‫ا‬َ‫ذ‬ِ‫إ‬ ِ‫ل‬ْ‫ي‬َّ‫ل‬‫ال‬ِ‫ب‬ْ‫ب‬َْ‫اْل‬‫وا‬ُ‫ق‬ِ‫ل‬َ‫غ‬َ‫و‬َ‫و‬ َ‫ة‬َ‫ي‬ِ‫ق‬ْ‫س‬َْ‫اْل‬‫وا‬ُ‫ك‬ْ‫و‬َ‫أ‬َ‫و‬ َ‫اب‬َ‫و‬‫وا‬ُ‫ر‬ِ‫م‬َ‫خ‬
ِ‫س‬ْ‫ح‬َ‫أ‬َ‫و‬ ٌ‫ام‬َّ‫م‬َ‫ه‬َ‫ال‬َ‫ق‬ َ‫اب‬َ‫ر‬َّ‫ش‬‫ال‬َ‫و‬ َ‫ام‬َ‫ع‬َّ‫ط‬‫ال‬ٍ‫ود‬ُ‫ع‬ِ‫ب‬ ْ‫و‬َ‫ل‬َ‫و‬َ‫ال‬َ‫ق‬ ُ‫ه‬ُ‫ب‬
ُ‫ه‬ُ‫ض‬ُ‫ر‬ْ‫ع‬َ‫ي‬)‫البخاري‬‫رواه‬.

131. ‫بأ‬َّ‫ن‬‫ال‬:9