1. A Primer on the Brain
and its Functions
Dr. Stan Kutcher
Katie Radchuck
Jillian Soh
Sun Life Financial Chair in
Adolescent Mental Health
Dalhousie University
IWK Health Centre
2. The Human Brain: A Brief Tour
The brain is a remarkable organ,
controlling everything from heart rate to
digestion to sexual functioning, and
everything in-between! It produces our
y g p
thoughts and speech, and allows us to
create works of art – complex activities
which help define our humanity.
3. The Human Brain: A Brief Tour
The human brain weighs approximately
1100-1200 grams, or around 2.5 pounds.
Your body and organs are made up
of cells, and the brain is no different.
Neurons are a type of nerve cell which form networks in your
brain to relay information. Glial cells tend to provide support to the
brain (nourishment mechanical support immune response etc )
(nourishment, support, response, etc.).
DID YOU KNOW?
The brain contains an estimated 100 BILLION nerve
cells, more cells than there are stars in the Milky Way
galaxy. That’s not all, glial cells are thought to outnumber
That s
the nerve cells by as many as 10 to 50 times!
Source: Encyclopedia Britannica. Astronomy. 2000
4. The Human Brain: A Brief Tour
Neurons are cells specialized to send and receive information.
Generally, a neuron is made up of three basic parts:
Dendrites: consisting of many branches this is
branches,
the area where the cell receives information
Soma (Cell Body): contains the cell nucleus
nucleus,
which acts like a blueprint for the production of
proteins and other materials that keeps the cell
p p
running smoothly
Axon: carries information received by the
y
dendrites, sometimes over long distances, to other
cells. The axon is sometimes covered in myelin
sheaths, another type of cell that speeds up the
signal.
5. What’s This “Information” Anyway?
In the same way humans use sounds to talk to one another and
share information, neurons use both electricity and chemicals to
talk to each other. These chemical messengers are called
neurotransmitters.
Just few e amples ne rotransmitters
J st a fe examples of neurotransmitters:
(Glutamate) (Dopamine)
(Serotonin)
(Epinephrine/
( cety c o e)
(Acetylcholine) Adrenaline)
Photo credit (CC 2.0): Anselm Hook
6. What’s This “Information” Anyway?
These neurotransmitters play a major role in the brain and
heavily influence consciousness, emotions, and behavior. In a
y , ,
group of people, if someone is whispering their ideas may not be
heard. In the same way, too little of a neurotransmitter may cause
communication failures between brain areas, affecting how we
think, feel, and act.
Photo credit (CC 2.0): Anselm Hook
7. What’s This “Information” Anyway?
You can see then, how important
communication is in the brain. If it is
disrupted, either through chemical
imbalances or problems with the
neurons themselves, this may
contribute to brain dysfunction and
mental illness.
Photo credit (CC 2.0): Anselm Hook
8. The Human Brain: A Brief Tour
Two basic layers of the brain can be
seen with the naked eye. There is the
outer layer, known as grey matter as
layer matter,
well as the inner layer, known as white
matter.
matter
The gray matter is made up of densely packed neuronal bodies,
whose long axons make up the white matter. Remember how axons
are sometimes covered in myelin sheaths? This myelin is quite
fatty, giving the tissue a white-ish color.
y, g g
9. Grey matter, containing the cell
bodies,
bodies is where all the thinking
happens. This is your brain’s
processing centre.
centre.
White matter, containing those
long axons, are like a super
highway.
highway. They transport
information to different parts
of your brain
brain.
Photo credit (CC 2.0): facemepls, MSVG
10. The Central and Peripheral
Nervous System
The brain, along with your spinal
brain
cord, makes up your body’s Central
Nervous System (CNS). From the
spinal cord extend nerve cells that
receive sensory information (such
as th roughness and h t of th
the h d heat f the
beach) and transmit that to the brain.
These outside nerves make up the
Peripheral Nervous System (PNS).
It’s a two-way street, The brain can
also send signals through the spinal
cord and PNS to control the
movement of your limbs and t k
t f li b d trunk.
11. The CNS and PNS
It takes around11.5 milliseconds to transmit a signal from the tip
of your toe to your brain. This may seem pretty fast but in some
cases – like when accidentally putting your hand on a hot stovetop
– this delay is too long and would cause your hand to burn.
Instead of sending a signal all the way to the brain and waiting for
a return signal to move your hand away, a network of cells within
the spinal cord receive the sensory information, then pass it on to
motor neurons, which are cells that control your muscles.
neurons muscles
Bypassing the brain like this is called a reflex. Your muscle will
contract causing you to pull away from the hot stovetop – it is only
after a short delay that your brain catches up and realizes your
hand hurts!
a d u ts
Photo credit (CC 2.0): Ndecam
12. The CNS and PNS
Speaking of signal transmission speeds, some nerve fibers
transmit signals faster than others. Usually it depends on
whether they are myelinated or not (remember that myelin
speeds up transmission!).
Think about when you stub your toe. You definitely feel it
right away since the touch signals reach your brain almost
instantaneously. However it’ll take a few seconds before the
pain signal will reach your brain, and when it does –
YEOWCH!
Photo credit (CC 2.0): Ndecam
13. So now we know what the brain is
made of. W know that different
d f We k th t diff t
parts of the brain communicate
with one another using
ith th i
neurotransmitters, and this
communication can extend
i ti t d
down the spinal cord to the rest
of your body.
But what does the brain actually DO
and HOW does it do it?
Photo credit (CC 2.0): perpetualplum
14. There are 6 functions of the Brain
1. Thinking & Cognition
2. Emotion Feeling
2 E ti & F li
3. Signaling (being responsive and
reacting to the environment)
4.
4 Perception & Sensing
5. Physical Functions
6. Behavior
15. Thinking and Cognition
Thinking & Cognition
includes all of our internal
mental processes and functions
Higher Cognitive Functions
Communicating Processing
Arithmetic Reading
Insight Focusing
Planning
Pl i Attending
Att di
Judgement Memory
Comprehension Contemplation
16. Thinking & Cognition
Overview FACT SHEET
Location: Frontal Lobes
Neural Pathways: 2-way
connection between
Your frontal lobes are responsible cortical and limbic areas
for the majority of your conscious
Main Neurotransmitters:
thought.
thought This area works closely with
Dopamine, serotonin, and
the limbic system, a section deep adrenaline
within the brain responsible for mood
mood,
emotion, and storage of memories.
17. Thinking & Cognition
The Limbic System
The limbic system includes several
brain structures: the amygdala,
hippocampus,
hippocampus anterior thalamic
nuclei, and limbic cortex.
The hippocampus, responsible
mainly for the storage of long term
long-term
memory, is one of the first places
affected by Alzheimer’s Disease
Alzheimer s Disease.
18. Thinking & Cognition
Attention
Your frontal lobes also include an
area called the prefrontal cortex,
which controls many of your cognitive
abilities, such as attention.
However, this area of the brain changes drastically during
adolescence,
adolescence and is one of the last brain areas to mature
completely!
19. Thinking & Cognition
Attention
Is your attention drifting right now? Don’t worry! Scientists
Don t
have measured attention in adolescents, and have discovered
that performance increases with age.
p g
So that means…
Yes, attentional
capacity might
improve as you
and your brain
matures!
Anderson et al (2001)
al.
20. Thinking & Cognition
Phineas Gage
We know that some parts of
p
the brain are specialized for
certain tasks. An injury to
specific, limited parts of the
brain can help scientists know
for sure what that part of the
brain is responsible for. Take
for example the case of poor
Phineas Gage.
Photo credit: From the collection of Jack and Beverly Wilgus.
21. Thinking & Cognition
In 1848, Phineas was a young man working
on clearing out some rock for the construction of a
railroad. An explosive was set off accidentally, thrusting
a large iron rod under Phineas’ left cheek bone and out
the top of his head. The force of the explosion was so
severe that the rod completely left Phineas to land 90
feet away, taking with it most of the left frontal lobe.
Photo credit (CC 2.0): Kevin Dooley
22. Thinking & Cognition
His recovery was long and at some points
bleak,
bleak but he eventually regained his memory and
physical strength. He suffered no motor or speech
impairments,
impairments however a startling change had occurred
with his personality and behavior.
Photo credit (CC 2.0): Kevin Dooley
23. Thinking & Cognition
He became rash,
where before he was mellow
mellow.
He used to be a good worker,
but now his colleagues could
not handle his temper. He had
trouble forming and executing
plans, didn’t think before he
acted, and often made choices
against his best interests.
g
Photo credit (CC 2.0): Kevin Dooley
24. Thinking & Cognition
Phineas Gage
Although the front left portion
of his brain was destroyed,
Phineas was still able to
function well. He could walk
and talk, since the brain areas
responsible for that wasn’t
affected.
However, the frontal lobes
are responsible for judgment,
planning, and d fi i your
l i d defining
personality. All of these
changed after his brain injury.
injury
Photo credit: From the collection of Jack and Beverly Wilgus.
25. Thinking & Cognition
Speech and Comprehension
Your brain also has specific
p
areas dedicated to speech and
language comprehension.
Broca’s Area
Mainly responsible for language
production. People who have
damage to this area are still able to understand language, and know
what they want to say, they just can’t ‘get it out’.
h t th tt th j t ’t ‘ t t’
Wernicke’s Area
Mainly
M i l responsible f l
ibl for language comprehension. P
h i People who
l h
have damage to this area can still produce speech but it tends to
have no meaning This is known as ‘word salad :
meaning. word salad’:
Example: “Colorless green ideas sleep furiously.”
26. Emotion is the ability to experience
feelings and to express those
feelings to others.
Happy
ppy Sad Anxious
Excited Depressed Worried
Calm Guilty Fearful
Peaceful Ashamed Nervous
Content Angry Panicky
Serene Irritated Inferior
Joyful Annoyed Inadequate
Pleased Resentful Lonely
Carefree Frustrated Discouraged
We can also call our emotions and
feelings “MOODS”
27. Emotion & Feelings
Overview FACT SHEET
Location: Prefrontal
Regulating your emotions is yet cortex, amygdala
another complex thing your brain has Main Neurotransmitters:
to do. Your prefrontal cortex Serotonin and dopamine
produces cognitive emotions
(“thinking with you head”) while the
amygdala produces instinctive
emotions (“thinking with your heart”).
ti (“thi ki ith h t”)
Serotonin and dopamine and two
very i
important neurotransmitters
t t t itt
needed to regulate your emotional
state.
state
28. Emotion & Feelings
Neural Correlates
Different parts of your brain are
active depending on what type of
emotion you are feeling.
For example, the top brain scan
shows which areas of our brain are
active when we feel sadness. The
bottom brain scan shows which areas
of our brain are active when we feel
happiness.
h i
The brain really does create all of
our emotions.
ti
29. Emotions & Feelings
Serotonin and Mood
Since the brain produces much of
p
what we feel, when something goes
wrong with th b i our
ith the brain
emotions can get messed up.
Clinical depression is
characterized by a persistent
persistent,
intense negative mood,
which affects a person’s
normal life
life.
Photo credit (CC 2.0): Alejandro Cordon
30. Emotions & Feelings
Serotonin and Mood
Research has found that
serotonin is important for
communication between the
prefrontal cortex and
amygdala areas of
the brain. Remember how
brain
those two areas are
important for regulating
emotions?
Photo credit (CC 2.0): Alejandro Cordon
31. Emotions & Feelings
Serotonin and Mood
Some people with major d
S l ith j depression d ’t
i don’t
have a good connection between the
prefrontal cortex and amygdala.
By increasing the amount of
serotonin in the brain with drugs,
this connection can be
strengthened and help people
regain a better mood
mood.
Photo credit (CC 2.0): Alejandro Cordon
32. Signaling is the brain’s way of responding
to a perceived threat, danger, or stress
from the environment.
Photo credit (CC 2.0): GE Healthcare
33. Signaling
Overview FACT SHEET
Location: Cortex,
Your brain is constantly alert, taking
alert thalamus, amygdala,
note of your surroundings. When it hippocampus
perceives a danger such as an
danger,
Main Neurotransmitters:
oncoming car, the brain begins a
Adrenalin, serotonin
p y
physiologic cascade with the help of
g p
neurotransmitters like adrenalin and
serotonin. Your heart rate and
alertness go up, more blood is
pumped to your muscles, and your
senses become sharper. Your brain
then makes a decision whether to run
from the danger, or stay and fight it.
34. Signaling
Fight or Flight
Sensory
Perception
(Ears, eyes, smell,
taste, touch)
t t t h)
+ Internal
Signals
When faced with DANGER, your 5 senses perceive it and sends a signal to the BRAIN
Your brain initiates
a Physiologic
Cascade
Heart Rate
Alertness
Perception
Now you are ready to
Tension FIGHT or FLEE for your
safety and protection
Photo credit (CC 2.0): Mangpages, Phillipe Put
35. Signaling
Anxiety
Sensory
Perception
(Ears, eyes, smell,
taste, touch)
t t t h)
+ Internal
Signals
Anxiety happens when the brain believes there is danger, but there isn’t any
Your brain initiates
a Physiologic This
Cascade
produces
Heart Rate feelings of
Alertness
ANXIETY
Perception
Tension
Photo credit (CC 2.0): Mangpages, flequi
36. Signaling
Anxiety
Normal anxiety happens to all of us.
A situation Which causes
can t i
trigger it:
it feelings of
f li f
anxiety:
First date
Preparing for an exam Apprehension
Performing at a concert Nervousness
Giving a speech Tension
Moving from home Edginess
Climbing a tall ladder Nausea
Etc. Sweating
Trembling
37. Signaling
Anxiety
Normal anxiety:
Is transient, which means that it will go away after a while
I t i t hi h th t ill ft hil
Does not significantly interfere with a person’s well-being
Does not prevent a person from achieving their goals
38. Signaling
Anxiety
Some people suffer from pathologic anxiety.
A situation, or nothing Which causes
can t i
trigger it:
it intense anxiety:
i t i t
Feels like a heart attack
First date
Feels like you’re dying
Preparing for an exam
Feels like you’re going
Performing at a concert
crazy or h i a
having
Giving a speech
nervous breakdown
Moving from home
Climbing a tall ladder This happens when there
is a dysfunction in the
NOTHING!
signaling mechanisms.
i li h i
39. Signaling
Anxiety
Pathological anxiety:
Is
I persistent, meaning symptoms stay around for a lot longer
i t t i t t df l tl
than they should
Is excessive, intense, and inappropriate to the situation –
feeling like you are having a heart attack before giving a
speech is not how the brain should react
Leads to impairment in a person’s everyday life where they
person s life,
may avoid people and act withdrawn in an attempt to avoid
trigger situations
gg
40. Perception is the way your
five senses work with your
brain to take in your
surroundings.
surroundings
Photo credit (CC 2.0): Mohamed Malik
41. Perception & Sensing
Overview
We have five senses that work together to give awareness of
our environment:
See Hear Smell Taste Touch
42. Perception & Sensing
Vision
For us to see, light must enter into our
pupils and hit the retina lining the back
y
of the eye.
Cones are cells in the retina that give
us our color vision, while rods are cells
vision
that give us black and white (night)
vision.
vision
The optic nerve carries the signal
through the lateral geniculate nucleus to
the back of the brain, the primary
visual cortex.
i l t
43. Perception & Sensing
Vision
The primary visual cortex transmits the
signal to two different areas of the brain:
Temporal lobes
Responsible for object recognition,
“what” the object is
what
Conscious processing
Parietal Lobes
Responsible for object location,
“where” the object is
Unconscious processing of the relationship
between the object and your body
44. Perception & Sensing
Vision: Blindsight
People who sustain damage to
their temporal l b may d
h i l lobes develop
l
a condition known as blindsight.
Since the temporal lobes are responsible for the conscious
processing of vision they would not be able to ‘see’ normally
vision, see normally,
and would be considered legally blind. However, their
unconscious,
unconscious spatial processing has not been damaged so
damaged,
even though they may not be able to identify objects in a room
they can walk around tables and chairs without bumping into
them. They can follow objects with their fingers and may even be
able to catch a ball thrown at them
them.
Photo credit (CC 2.0): Jim Simonson
45. Perception & Sensing
Hearing
Many tiny hairs in your inner
ear vibrate to sounds in the
environment.
environment Those vibrations
are felt by cells in the ear and the
signal is transferred along the
g g
brain to eventually reach the
primary auditory cortex.
DID YOU KNOW?
As people age their ability to hear very low and high
age,
frequency noises diminishes. An anti-loitering alarm was
developed that plays a high-pitched, annoying noise that
high pitched,
only teenagers can hear. Talk about discrimination!
46. Perception & Sensing
Smell
Smell exists as tiny
molecular odorants that travel
up your nose to be detected
by cells in the olfactory
epithelium. This signal travels
p g
through the olfactory nerve to
your brain, where the signal
is processed by the olfactory cortex. Some of the signal makes it to
the limbic system, where long-term, emotional memories are stored.
This is why smells can sometimes help you remember strong
memories, maybe of your home or childhood!
Photo credit (CC 2.0): DrJimiGlide
47. Perception & Sensing
Taste
Taste buds which cover the surface
of the tongue allows us to distinguish
different flavors in our food There are
food.
five basic tastes:
Sweet
Sour
Salty
Bitter
Umami (savoury)
Photo credit (CC 2.0): Zoe Shuttleworth
48. Perception & Sensing
Taste
Information from the taste buds travel up cranial nerves to reach
the brain stem, where the signal is passed onwards to the primary
gustatory cortex.
cortex
DID YOU KNOW?
Not everyone perceives food the same way! Some
people have a lot more taste buds than average, and
are known as ‘super tasters’. Your genes determine
super tasters
whether you are a ‘super taster’, ‘taster’, or even a
‘non-taster’. Super tasters tend to be very sensitive to
non taster .
different foods, especially bitter things like broccoli
and coffee, and may be picky eaters.
, y p y
Tepper et al. 2009; Photo credit: Zoe Shuttleworth
49. Perception & Sensing
Touch
Your body is full of touch
receptor cells near the surface of
the skin. When activated they
skin activated,
send a signal up to your brain to
let it know. Some areas of your
y
body have many more touch
receptors than others, and thus
have a larger representation in
the brain, in a place called the
somatosensory cortex.
Photo credit (CC 3.0): btarski
50. Perception & Sensing
Touch
A homunculus is a
representation of what a human
would look like if made in the same
proportions as the brain area
assigned to it. The hands and facial
areas, especially th li and
i ll the lips d
tongue, are highly sensitive!
Dr. Penfield, the famous Canadian
neuroscientist (yes, the ‘burnt toast’
guy!) came up with the homunculus
by mapping limb locations to different
areas of the brain.
f th b i
51. Signaling is the brain’s way of responding
to a perceived threat, danger, or stress
from the environment.
Your brain takes
care of many
different physical
functions, such as
digestion, breathing,
controlling your
muscles, etc.
Photo credit (CC 2.0): GE Healthcare
52. Physical Functions
Voluntary Movement
In the same way that
different brain regions
are assigned for
sensing different areas
of your body, different
y y,
brain regions control
different areas of your
body. Places where
fine motor control is
needed, such as your hands and mouth (for producing speech and
eating), take up a larger area in the brain! This place is called the
motor cortex.
t t
53. Physical Functions
Voluntary Movement
Your prefrontal cortex – which if you
remember is where all your thinking
happens – sends a signal to the motor
cortex area assigned to a body part.
This signal travels down the spinal
g p
cord to alpha motor neurons, which
tell muscles to contract. This whole
process allows us to produce thought-
directed, voluntary movements.
This entire complex arrangement is known as the somatic
nervous system.
system
54. Physical Functions
Involuntary Movement
What about involuntary movement?
Stuff you can’t control consciously?
Your heart needs to keep beating
and your stomach needs to keep
churning for y to stay alive. If y
g you y you
had to consciously think about every
breath you took you probably would
be too distracted to think about much
else. This is where the autonomic
(from ‘automatic’) nervous system
comes in.
Photo credit (CC 2.0): David DeHetre
55. Physical Functions
Involuntary Movement
Your autonomic system is basically in
charge of all your internal organs, and
controls what they do unconsciously
(although some things, like your breathing,
can be taken over by the conscious mind).
y )
It is divided into two parts: the
Sympathetic Nervous System, and the
Parasympathetic Nervous System.
56. Physical Functions
Involuntary Movement
Sympathetic Nervous System
Remember h
R b how signaling and anxiety works?
i li d i t k ?
Your sympathetic nervous system controls that
‘fight or flight mechanism (makes the heart pump
fight flight’
faster, inhibits digestion, raises blood pressure,
etc.).
etc ) It also maintains equilibrium or homeostasis
equilibrium, homeostasis.
Stuff like making sure your body temperature
is just right, and balancing your
blood sugar levels.
Photo credit (CC 2.0): Mark Robinson
57. Physical Functions
Involuntary Movement
Parasympathetic Nervous System
While th
Whil the sympathetic nervous
th ti
system is most active when you’re
stressed,
stressed the parasympathetic
nervous system works when you are
resting,
resting so it’s known as the ‘rest
it s rest
and digest’ system. Think of it
working in the opposite direction,
instead of speeding up your heart
rate it slows it down. It lowers your
y
blood pressure. Since, at rest, your
body can expend energy to relax and
eat, much more saliva is produced.
58. Behavior is simply
the way we act,
usually in
response to our
environment. It
includes
everything ffrom
running to joking,
from reading t
f di to
Photo credit (CC 2.0): Jamie Davis
working.
59. Behavior
Overview
Teens don’t ‘get’ their parents.
What’s with all the rules and
restrictions? And parents don’t like th
t i ti ?A d t d ’t lik the
things teens do – they always seem to
be experimenting and taking
unnecessary risks.
This seeming rift between teens and
adults has a lot to do with behavior,
and behavior has a lot to do with the
brain.
Photo credit (CC 2.0): Ollie Crafoord
60. One example of a behavioral difference is
Behavior motivation. Motivation is your drive to do
y
Motivation
stuff – like studying hard to do well on a test,
or finishing a marathon, or beating one more
level of a video game.
Photo credit (CC 2.0): shirokazin
61. Behavior
Motivation
Motivation is influenced heavily by
the reward pathway in the brain. A
reward d
d doesn’t h
’t have t b
to be
something physical, it can be getting
a good mark or a positive feeling
feeling.
Drug addiction causes your brain to
constantly seek out that positive
‘feeling’, and your brain becomes
dependant on it as a reward. The
danger comes when that feeling can
only be achieved by drugs!
y y g
Photo credit (CC 2.0): Ollie Crafoord
62. Behavior
Motivation
In teens, the reward pathway of the
brain is stronger than in adults. Also,
the
th cognitive parts of the brain th t
iti t f th b i that
think about things logically and weighs
the pros and cons are not as
developed in teens. This means teens
may be motivated to try riskier
behaviors and be more impulsive than
adults would be, and are more prone
to push beyond their limits and
g g
boundaries without weighing
consequences (Smith et al., 2011).
63. Behavior This isn’t always a bad thing.
Motivation Since the brain matures in this way,
Si th b i t i thi
young people can be extremely
passionate about the things th
i t b t th thi they
care about, they work hard to
achieve things that are important to
them. They open their eyes to the
world and have new experiences,
and become better people for it.
It’s all about the choices you
make.
make
Photo credit (CC 2.0): James Tosh
64. So now we know the
six basic functions of the
brain, but how does such
a complex organ develop?
NewScientist (2009)
suggests that there are 5
different ‘ages’ of the brain:
ages
1. Gestation
2. Childhood
3. Adolescence
4. Adulthood
5.
5 Old Age
A
Photo credit (CC 2.0): Neil Conway
65. Gestation
Overview
Gestation is the stage of development
where you are still in your mom’s womb.
It is this time where your brain undergoes
initial development, and your cells
differentiate to create your first neurons
y
(this process is called neurogenesis).
Neurogenesis is a hot topic right now
now,
because while people are really good at making new neurons when
they are fetuses, it gets much harder when they are adults. If we learn
fetuses adults
how to create new neurons where we want them, we may be able to
help people with brain diseases and spinal cord injuries
injuries.
66. Childhood
Overview
Childhood is the stage where our
brains probably undergo the biggest
changes.
changes It is this time where we
learn language, how to store
memories, and how to think.
,
Timeline:
6 years:
2-3 months: 18 months: apply logic and trust, understands
cortex develops develop a sense of self personal thought process
6-12 months: 3-4 years:
y
frontal lobe sense that other people
develops have minds too
67. Adolescence
Overview
Adolescence is the teenage
years. It is around this time that your
brain areas start to fully mature and
develop. Your sensory and motor
areas are the first to mature, which is why teens can be ‘sensation
, y
seekers’. Your prefrontal cortex matures last, which helps in decision
making, emotional control, and temper.
Most teens pass through these years without severe or prolonged
difficulties,
difficulties but 15% of teens will experience significant mental health
problems during their adolescent years.
68. Adolescence
Overview
Adolescence is the time where
your brain gets rid of neural
pathways that it doesn’t need.
th th t d ’t d
When you’re young, you have
a high volume of gray matter in
your brain. During adolescence,
this gray matter is pruned away
away.
This is thought to make the brain more efficient. What gets removed
depends a lot on usage. It’s really ‘use it or lose it!’ It is important to
It s use it!
keep your brain active and healthy during these years.
69. Adulthood
Overview
You ve
You’ve finally made it to your adult
years! People’s brains peak around
the age of 22 This is when they can
22.
process things the fastest and learn
new things easier. When y hit 27
g you
years, your brain will progressively
start to decline. However, adults are excellent at crystallized
intelligence, or wisdom, which is the ability to use and apply
everything you’ve learned up till now.
You can keep your brain sharp and slow down that decline by being
mentally and physically active.
active
70. Old Age
Overview
In your golden years, you brain is in the
most danger of deteriorating. Death of brain
cells i th hi
ll in the hippocampus area can l d t
lead to
memory loss. Again, by keeping fit and
eating healthy you can stimulate brain
healthy,
cell growth and slow this decline.
The elderly are more prone to diseases
such as Alzheimer’s – plaques and tangles are seen in the brain
wrapped around cells responsible for memory and retrieval.
Parkinson’s is another disease which mainly affects the elderly, and
is
i caused b th d th of cells responsible f movement.
d by the death f ll ibl for t
71. Old Age The chance of experiencing a stroke also increases
Overview when you’re older. A stroke occ rs when the blood
hen o ’re older occurs hen
supply to the brain has been disturbed. A portion of
your brain may lose its functioning (causing paralysis
on one side of the body, loss of speech, etc.).
Neuroplasticity is the brain’s ability to rearrange
brain s
neural pathways and repair itself. It used to be thought
that this could only occur in very y
y y young p p , but
g people,
recent research has shown that neuroplasticity can still
occur in older adults, even in the elderly. There’s a lot of
science being done now to see if we can enhance
neuroplasticity to help treat stroke patients and speed
up their recovery
recovery.
Photo credit (CC 2.0): TheArches
72. Think upon this…
We’re i
W ’ using
the Brain
to study
the Brain
And there’s still a lot to learn! What
there s
you’ve read here is just the tip of our
current knowledge, and our current
knowledge is just the tip of what is going
on in that spongy mass of tissue. As
science advances, the brain will come to
better d t d it lf S k
b tt understand itself. So keep learning!
l i !
Photo credit (CC 2.0): dierk schaefer
73. Sun Life Financial Chair
In Adolescent Mental Health
For more information visit
WWW.TEENMENTALHEALTH.ORG
74. References
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Chambers, R.A., Taylor, J.R., Potenza, M.N. 2003. Developmental Neurocircuitry of
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