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Basic Neuroscience:
Introduction
Bellringer
1)
The Journey…
 The
Neuron
 The
case of
Phineas Gage
 Brain
 The
Plasticity
Adolescent
Brain
Introduction (2min):
What is Neuroscience?
A
scientific study of how the Nervous system
(CNS and PNS) carries out its function
What
are the Nervous System’s functions?
 The
Nervous System includes all thoughts,
perceptions, bodily actions, behaviors, and
ultimately: Consciousness
Evolution of the brain
 The
Human Brain has
evolved from the inside
out
 Lower
regions like the
brainstem are generally
more ancient than higher
regions, such as the
frontal cortex.
 Basic survival functions
like breathing are
controlled in the lower
brainstem
 The large prefrontal
cortex in humans is a
late evolution
Brain structures and it’s functions:
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Structure
Major Function
Frontal Lobe
Motor cortex
Basal ganglia
Broca’s area
Prefrontal cortex
Plans and executes voluntary movements
Smoothes movements
Controls speech
Planning, impulse control
Parietal lobes
Somatosensory cortex
Association cortex
Projection area for body senses
Location of body and objects in space
Temporal lobes
Auditory cortex
Wernicke’s area
Inferior temporal cortex
Auditory information
Language area – meaning
Visual identification of objects
Occipital lobes
Primary visual cortex
Visual association cortex
Brain Stem
Medulla
The reticular formation
Cerebellum
Projection area for visual information
Processes components of visual information
Regulates autonomic responses: heartbeat, blood
pressure, digestion, and swallowing
Controls our different levels of arousal and awareness
Coordinates
posture, balance, muscular activity
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What is the brain made of?
 Cells
- distinct,
individual cells, or
networks of fused cells
 Cell
types: neurons,
glia, capillary, and
endothelial cells
The Neuron
The Structure of a Neuron
How Neurons Communicate
Neurons

Neurons are responsible for
information transmission throughout
the nervous system
The Structure of a Neuron
Receives information
from other neurons
Transports
information
Sends out
information
Contains
the nucleus
Protects the Axon
How Neurons Communicate
Communication
within
a neuron is
electrical
Communication
between
neurons is
chemical
Neural Electrical Activity

Axons propagate action potentials (sudden
depolarization of membrane)

The electrical input from lots of different neurons
is summed together. If it exceeds a threshold
then the receiving neuron will also generate an
action potential.
Action potential
Neurons and Synapses
Nervous System Subdivisions
Let’s try it:
1)
2)
3)
4)
1 student in charge of stopwacth
7-10 students line up side by side
Now place your right hand on your classmate’s shoulder
First person in line will squeeze the shoulder of the person next
to them (not too hard)
5) As soon as you feel your shoulder being squeezed pass “the
message” (squeeze) on to the person to their right until it gets to
the last person in line.
6) Last person will say STOP, at which point student should take
note of the final time.
7) Try again but this time holding hands.
8) First student will lightly squeeze the hand of student to their
right and so on.
9) Take note of final time and compare.
1) Which trial took the longest? Why do you think that
happened?
Are you “Left-Brained” or
“Right-Brained” ?.....
What we know…

Left hemisphere




Language
Math and logic skills
More analytical, analyzing wholes into pieces
Right hemisphere




Spatial perception
Solving spatial problems
Drawing
Face recognition
You are: “Whole-Brained”




Remember, these differences in
hemispheric performance are for people
whose two hemispheres can no longer
communicate (usually due to injury)
When “normal people” are performing a
task, the two hemispheres are constantly
interacting and sharing information
This is why it is not very accurate to say
someone is “left-brained” or “right-brained”
Rather, nearly all of us are “whole brained”
Components of Emotion
An emotion is a complex psychological
state that involves three components:
Physical
Behavioral
Cognitive
A physiological
state of arousal
triggered by the
autonomic
nervous system
An outward
expression including
facial expressions,
movements and
gestures
An appraisal of the
situation to determine
which emotion we are
experiencing and how
intensely
Integrated Theory of Emotion

LeDoux (1996) contends that there are
different brain systems for different emotions

Fear, for example, does not require higher-level
cognitive processing and is generated almost
instantaneously by the amygdala

More complex emotions, however, such as love or
guilt, that do not require instantaneous responding for
survival, may require higher-level processing
The Case of Phineas Gage
The case of Phineas Gage (1848)
 25-yr old construction worker
 3.5 foot long tamping iron through cheek and
out of skull
 Regained consciousness, talk, walk,
 No impairment of; speech, learning, memory,
intelligence



Dramatic personality changes
Post-mortem – damage to both areas of
frontal lobe for processing emotions and
making rational decisions
Localisation of function
Video: Phineas Gage
https://www.youtube.com/watch?v=NFO6ts6vZic
The Adolescent Brain:
What was learned?



Adolescence is a period
of profound brain
maturation.
We thought brain
development was
complete by
adolescence.
We now know
maturation is not
complete until about
age 25!
ADOLESCENT BRAIN
DEVELOPMENT

Underdevelopment of the frontal lobe/prefrontal cortex
and the limbic system make adolescents more prone to
“behave emotionally or impulsively”

Adolescents tend to use an alternative part of the brain–
the socio-emotional system rather than the cognitivecontrol system to process information
The Adolescent Brain:
Adolescent Brain
Adult Brain
Hot And Cold Cognition

Teen decisions are unlikely to emerge from a logical
evaluation of the risk/benefits of a situation –

Rather decisions are the result of a complex set of
competing feelings:




desire to look cool,
fear of being rejected,
anxiety about being caught,
excitement of risk, etc.
PFC
I hate school;
I am going to
skip classes!!
amygdala
This imbalance leads to...
 planned thinking
 impulsiveness
 self-control
 risk-taking
more “hot” talking, less “cool” talking
GOOD NEWS!
The pruning of the PFC neurons
produces a more efficient PFC by young
adulthood
I am
planning
for the
future
amygdala
PFC
Overproduction And Pruning

Brain development occurs in 2 basic stages– growth
spurts/overproduction of neurons and pruning

Critical phases: in utero
0-3 years
10-13 years
overproduction

Overproduction results in significant increase in the
number of neurons and synapses

Exuberant growth during these 3 phases gives the brain
enormous potential
Brain Development



When pruning is complete, the brain is faster and more
efficient.
But, during the pruning process, the brain is not functioning
fully.
Maturation occurs from the back of the brain to the front.
(prefrontal cortex)
PRUNING

These 3 critical phases are quickly followed by a process
in which the brain prunes and organizes its neural
pathways

LEARNING is a process of creating and strengthening
frequently used synapses (brain discards unused
synapses)

Brain keeps only the most efficient and “strong”
synapses

Children/teens/parents/ need to understand that they
decide which synapses flourish and which are
pruned away
PRUNING

“USE IT OR LOSE IT”– Reading, sports, music, video
games, x-box, hanging out—whatever a child/teen is
doing—these are the neural synapses that will be
retained

How children/teens spend their time is CRUCIAL to
brain development since their activities guide the
structure of the brain
Independent Practice
Reflection:
1st) Choose one of the two and write in full paragraph
format:
 INFORMATION – help a teenager understands how their
brains develop; how brain function impacts behavior; and
process for re-wiring the brain

HOT/COLD COGNITION – during stressful, emotional, or
threatening situations “problem solving” information in the
cortex is not easily accessed; how could a teenager
practice concrete ways to access information and skills?
2nd) Write 3 things you have learned from today’s lecture
2nd) Write 3 things you have
learned from today’s lecture
END
The Adolescent Brain and
Alcohol
From AMA pub 9416



The brain goes through dynamic change during
adolescence, and alcohol can seriously damage
long- and short-term growth processes.
Frontal lobe development and the refinement
of pathways and connections continue until age
16, and a high rate of energy is used as the
brain matures until age 20.
Damage from alcohol at this time can be
long-term and irreversible.
The Adolescent Brain (cont.)



In addition, short-term or moderate
drinking impairs learning and memory far
more in youth than adults.
Adolescents need only drink half as much
as adults to suffer the same negative
effects.
To see an animation of GABA receptors and
the influence of alcohol, click here.