A short introduction to the effects

1. STRESS AND THE BRAIN
INTRODUCTION TO PSYCHOLOGY
D. BAMBIC

2. A metaphor for neurons
 Your brain is made up of
100 billion nerve cells -
about the same as the
number of trees in the
Amazon rainforest.
 Learning is about making
connections between all
these neurons.
 Stress impedes these
connections.

3. THE EFFECTS OF STRESS ON THE BRAIN
 It is well known that
toxic stress can harm the
brain’s ability to form
new memories, recall
existing ones and even
cause neurons to ‘shrink’.
 Stress can re-shape our
brains.

4. Prenatal stress
 Prenatal stress can
change the foetus’ brain
permanently.
 Prenatal stress can lead
to mood disorders and
learning disabilities
later in life.
 Stress in early
childhood can lead to
aggression and serious
health problems in
adult years.

5. Continued growth of brain
 A baby’s brain continues
to develop long after
birth.
 Stimulation and
experiences are the
nourishment for brain
development.
 Stress is a negative
experience that we must
mitigate whenever
possible.

6. Learning problems and mood disorders
 Stress in early life, even
in the womb, can later
lead to undesirable
changes in behavior and
the ability to learn and
remember. Other
consequences may be
substance abuse and
psychiatric disorders.

7. Even short term is not good!
 Prenatal stress can change the
brain forever.
 Stress changes how genes are
expressed throughout life.
 Even short-term stress can be
harmful. Laboratory mice,
which were immobilized for
five hours and subjected to
loud rock music. The ordeal
reduced the number of
delicate fibers that carry
signals between neurons, an
MRI brain scan of the
stressed-out mice showed.

8. Stress and memory
 Chronic over-secretion of stress
hormones adversely affects brain
function, especially memory. Too
much cortisol can prevent the
brain from laying down a new
memory, or from accessing
already existing memories.
 Sustained stress can damage the
hippocampus , the part of the
limbic brain which is central to
learning and memory. The
culprits are "glucocorticoids," a
class of steroid hormones
secreted from the adrenal glands
during stress. They are more
commonly know as
corticosteroids or cortisol .

9. Fight or flight response
 During a perceived
threat, the adrenal
glands immediately
release adrenalin. If the
threat is severe or still
persists after a couple of
minutes, the adrenals
then release cortisol.
Once in the brain cortisol
remains much longer
than adrenalin, where it
continues to affect brain
cells.

10. Shrinking hippocampus
 Long lasting, chronic
stress also physically
affects the brain.
 After laboratory rats
were tightly restrained
for six hours daily for 21
days, without food or
water, the animals'
hippocampus - a brain
region involved in
learning and memory -
shrank by 3%.

11. Cortisol and memory formation
 Have you ever forgotten
something during a stressful
situation that you should have
remembered? Cortisol also
interferes with the function of
neurotransmitters, the chemicals
that brain cells use to
communicate with each other.
 Excessive cortisol can make it
difficult to think or retrieve long-
term memories. That's why
people get befuddled and
confused in a severe crisis. Their
mind goes blank because "the
lines are down." They can't
remember where the fire exit is,
for example.