sleep and dream

1. One third of our lives spent
doing it!(SLEEP)

2. What is Sleep
 A state of
 (1) sustained immobility
 (2) characteristic posture accompanied by
 (3) reduced responsivity to external stimuli

3. Why are some reasons we need sleep?

4. Sleep allows our body to rest and repair
itself!
 Sleep:
 Allows us to rest
 Gives us energy
 Improves mood
 Makes us alert
 Helps with memory

5.  Sleep appears to be an essential physiological process for
humans and for most other animals, other than very
simple ones with small brains. When deprived of sleep,
we function less effectively, feel tired and irritable, make
more mistakes, are less creative and, if taken to extremes,
ultimately die.
 In the same way as a feeling of hunger reminds us of
the basic human need to eat, a feeling of sleepiness
reminds us of our essential need to sleep.

6. Sleep Need
 “Sleep need” is the amount of sleep we need to stay alert
during the day.
 How many hours do teenagers need to sleep each night? 8 –
10 Hours!

7. Sleep debt
Sleep debt is when we get less sleep
than we need.
We need: We get: Sleep debt:

8. What does sleep debt affect?
 Alertness
 Learning and memory
 Mood
 Energy
 Control and coordination

9. Sleeping is an active process
 Some parts of our body
slow down:
 Breathing
 Heart rate
 Digestion
 Other parts speed up:
 Our BRAIN

10. Brain activity is measured as electric waves

11. BRAIN WAVES
 Your brain is made up of billions of brain cells called neurons,
which use electricity to communicate with each other. The
combination of millions of neurons sending signals at once
produces an enormous amount of electrical activity in the
brain, which can be detected using sensitive medical equipment
(such as an EEG), measuring electricity levels over areas of the
scalp.
 The combination of electrical activity of the brain is commonly
called a Brainwave pattern, because of its cyclic, 'wave-
like' nature. Our mind regulates its activities by means of
electric waves which are registered in the brain, emitting tiny
electrochemical impulses of varied frequencies, which can be
registered by an electroencephalogram

12.  1Beta emitted when we are consciously alert, or we feel
agitated, tense, afraid, with frequencies ranging from 13 to 60
pulses per second in the Hertz scale.
 2Alpha when we are in a state of physical and mental
relaxation, although aware of what is happening around us, its
frequency are around 8 to 13 pulses per second.
 3Theta more or less 4 to 7 pulses, it is a state of somnolence
with reduced consciousness.
 4Delta when there is unconsciousness, deep sleep or catalepsy,
emitting between 0.5 and 4 pulses per second.

13. Different types of brain waves exist during
our sleep cycle

14. There are two types of sleep: REM
and Non-REM
 REM: Rapid eye movement
 Dreaming occurs during REM sleep.
 NREM: Non-REM sleep
 The American Academy of Sleep Medicine (AASM)
divides NREM into three stages: N1, N2, and N3, the last
of which is also called delta sleep or slow-wave sleep.

15. Stage 1
 NREM stage 1:
This is a stage between sleep and wakefulness. The muscles
are active, and the eyes roll slowly, opening and closing
moderately.
 transition of the brain from alpha waves having
a frequency of 8–13 Hz (common in the awake state)
to theta waves having a frequency of 4–7 Hz.
 drowsy sleep

16. STAGE 2
 NREM stage 2:
 theta activity is observed
 sleepers become gradually harder to awaken
 muscular activity decreases, and conscious awareness of
the external environment disappears.
 This stage occupies 45–55% of total sleep in adults.

17. STAGE 3
 NREM stage 3:
 Formerly divided into stages 3 and 4, this stage is
called slow-wave sleep (SWS).
 The sleeper is less responsive to the environment;
many environmental stimuli no longer produce any
reactions.
 Delta waves are activated

18. REM SLEEP
 where most muscles are paralyzed.
 REM sleep is turned on.
 This level is also referred to as paradoxical
sleep because the sleeper, although exhibiting
EEG waves similar to a waking state, is harder
to arouse than at any other sleep stage.

19. REM SLEEP
 Oxygen consumption by the brain is higher than when the
sleeper is awake. An adult reaches REM approximately
every 90 minutes.
 Most memorable dreaming occurs in this stage.
 Heart rate and breathing rate are irregular during REM
sleep
 Body temperature is not well regulated during REM
sleep

20. Dreams
 Dream is a word used to describe the subconscious experience of a
sequence of images, sounds, ideas, emotions, or other sensations usually
during sleep, especially REM sleep
 There is no neurologically agreed upon, biological definition for
dreaming
 Dreaming is stimulated by the pons
 But there is a lot that is unknown about dreams and the purpose of
dreams is interpreted in many different ways
 Sigmund Freud postulated that dreams are the symbolic expression of
frustrated desires that have been relegated to the unconscious mind,

21. Activation Synthesis theory
 Certain processes in the cerebral cortex have been studied
by John Allan Hobson and Robert McCarley.
 In their activation synthesis theory, they propose that
dreams are caused by the random firing of neurons in
the cerebral cortex during the REM period.

22. Lucid Dreaming
 Lucid dreaming occurs when dreamers realize that they
are dreaming (lucid dreaming can occur with varying
levels of awareness and dream control)
 The dreamers are sometimes capable of changing their
dream environment and controlling various aspects of
their dream.

23. What is the purpose of dreams?
 Freud proposed that dreams protect sleep, which might be
disturbed by the arousal of unacceptable wishes
 Ferenczi proposed that dreams may communicate
something that is not being said outright (subconscious
thoughts)
 Another idea is that dreams helps the mind run tests of its
Emergency Broadcast System, a way to prepare for
potential disaster. For example, when new mothers dream
about losing their babies, they may actually be rehearsing
what they would do or how they would react if their worst
fears were realized.

24. FACTS
 Humans spend about 6 years dreaming
 Dreams are generated in the forebrain
 Most common emotion experienced during dreaming is
anxiety
 Twelve percent of people dream only in black and white

25. Simple habits for improving sleep
 Only go to bed when you are sleepy. If sleep does not come
reasonably quickly - within, say, 20-30 minutes or even less - get
up and try again later (try to avoid bright lights while you are up,
though).
 Do not oversleep, as it may leave you feeling unrefresh and
sluggish the next day, as well as confuse your internal biological
clock for subsequent nights.
 Use your bed only for sleep not for television viewing,
telephone calls, work, etc. Try to establish a strong mental
association between the bedroom and sleeping.
 If possible, try to keep your sleep and waking times regular,
even on weekends, in an effort to “train” your biological clock.
Make sleep a priority, even when time is short.

26.  Do not engage in strenuous exercise, heavy meals or a hot bath just
before going to bed: all of these activities work to increase body
temperature which will make it harder to fall asleep. A lukewarm bath
or shower, however, can help relax your muscles and make falling
asleep easier.
 A little moderate exercise, such as an evening stroll, can help
you sleep, and more strenuous exercise earlier in the afternoon is also
beneficial. But avoid intense exercise too close to bedtime (within 3-4
hours).
 Make sure your evening meal is not too light and not too heavy, and a
good two or three hours before bedtime. High protein foods might
keep you awake at night, and may be better options for lunchtime.
Foods containing tryptophan (e.g. bananas, dates, nut butters, tuna,
turkey, yoghurt, milk) and carbohydrates like bread or cereal, on the
other hand, may help encourage drowsiness and sleep. As with
everything else, a balanced diet with plenty of fresh fruits, vegetables
and whole grains will help in the long term.

27.  Avoid caffeinated drinks like coffee, tea, cola, “energy” drinks, etc,
near bedtime (certainly within 3-5 hours, and preferably much longer
than that), and try not to drink too much of anything too late in the
day, in order to avoid bathroom trips. A hot milk or herbal tea before
bed, however, may help encourage sleep.
 Avoid other stimulants, such as alcohol or tobacco, before going to
bed. Alcohol may help you get to sleep in the first place, but it will
disturb your sleep later, preventing you from entering the deeper
restorative stages of sleep, and causing you to wake frequently during
the night.
 Relaxing bedtime habits or rituals, such as reading or writing, just
before bed can help to relax you and take your mind off any anxieties
you might have about sleeping. Bedtime rituals are particularly
important for children, especially when they reach the stage, as most
do at some point, of resisting bedtime and encountering difficulties
falling asleep.

28.  Similarly, meditation, relaxation exercises, soothing music or
just a period of calm deep breathing beforesleep can all help to
calm you down and alleviate stress and anxiety.
 Sleep on a good comfortable mattress which helps you
maintain a good sleep posture, and a comfortable pillow that
allows for efficient unobstructed breathing and a good neck and
spine position during sleep (for more details, see the section
on Sleeping Positions).
 Avoid exposure to bright light (especially blue light) close to
bedtime, as it may confuse circadian rhythms and
trigger awakening rather than sleeping processes. Try to get
regular exposure to outdoor light during the day (in particular,
direct sunlight straight after waking can help establish
good circadian rhythms).

29.  Ensure that the bedroom is not too hot or too cold. Old-
fashioned remedies like wearing bed-socks can really help in
cold weather, as they slow heat loss to the extremities and so
make it easier to fall asleep.
 Ensure that the bedroom is fully dark (use blackout blinds is
necessary), and that it is isolated, as far as possible,
from intrusive noises (use earplugs or white noise machines if
necessary).
 Use the bathroom before sleep in order to avoid unnecessary
trips to bathroom during the night. If you do have to use the
bathroom at night, use the minimum possible amount of light to
navigate.
 If you are having problems sleeping at night, avoid naps during
the daytime, as they tend to “borrow” from the next
night’s sleep, unless they are very short (10-20 minutes).

30.  If you are not sleeping well, avoid watching the
clock and do not put mental pressure on yourself or
get upset about the situation - you cannot force
yourself to sleep, and this can only be
counterproductive.
 Write down any troubling thoughts before bed-time,
so that they won’t dwell on them through the night.
 Sedatives should be taken only as a last resort, but
they may help to establish a sleep habit if taken as a
temporary short-term solution.