Welcome!!

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Welcome!!
Warm-Up
On the sheet provided, label the
Neuron correctly… then explain
the three types of Neurons on the
bottom of the paper
The Brain
The Brain
• The most important
structure in our bodies
• Controls most of human
thought and emotion.
• From pain to pleasure it all
comes from the brain.
The Brain
Made up of millions of densely packed
neurons and actually it feels no pain.

Pain actually stops once something reaches
the actual brain.

It was once commonly believed that if
you damage brain cells (through
drinking, smoking, hitting your head, or
just holding your breath for a REALLY
long time) they would never grow back

And you would be in big trouble...
There is some research now
that points to the contrary.
• So, if you have some brain
damage, do not worry...
– Some of our brain functions are
flexible and if one part goes out,
others will try to compensate and
continue to function.
• This is called Brain Plasticity
Brain Plasticity
• The idea that the brain, when
damaged, will attempt to fix
itself
• It does this by rerouting connections
to avoid damaged areas
• Think of it this way…you are on the
way for a romantic date when you
find the highway flooded…
– Would you give up??
– No, you would use Mapquest to get
new directions
• This is essentially what our
brains try to do when damaged.
Brain Plasticity
• Unfortunately, as we age the ability of brain
plasticity working decreases.
– Children’s brains are more plastic than adults.
• The lesson here is…???
– if you are going to damage your brain, do it at a very
young age.
Before we talk about brain structures, lets
quickly go over some of the ways scientists
learn about the brain
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Ways we Study the Brain
Accidents
Lesions
EEG
CAT Scan
PET Scan
MRI
Functional MRI
Accidents
Every so often someone gets
smacked in the head REALLY
hard and from that injury we
learn about the brain.
The Phineas Gage Story
• Personality and behavior
changed after damage to his
Frontal Cortex
What did this tell us?
– different parts of the brain
control different aspects of who
we are.
Lesions/Ablations
• Removal or destruction
of some part of the
damaged brain.
– Sometimes done
intentionally
• Frontal Lobotomy
– Often used for mentally
unstable patients
An ablation of a rat’s brain
Ok, that was a piece of cake, now on to the
heart of this unit:
Brain Anatomy and Function
Before we begin…
• Realize, that for this class, EXACT
areas of the brain are not all that
important.
• As long as you understand the general
function and location you are going to
do fine.
• So here we go…
Brain Structures
The brain can be
broken down into
three areas:
1. Hindbrain
2. Midbrain
3. Forebrain
Hindbrain
• Lowest part of the brain, on top of our spinal cord
• Controls most of our basic biological functions.
• i.e. heartbeat, breathing, ect.
The brain in
purple makes up
the hindbrain.
Medulla Oblongata
Located just above the
spinal cord
Involved in control
of
• blood pressure
• heart rate
• breathing.
If you get hurt
in the MO you
should just pack it in
Pons
Located just above the
medulla
• Relays information
to other parts of
the brain from
the hindbrain
Cerebellum
Located at the bottom rear
of the brain
• Looks like a mini version of
the brain - “little brain”
• Controls balance,
coordination, and fine
muscle movement
Cerebellum
Midbrain
Located in the middle of our brain
and is the pathway that connect
the hb and fb
If stimulated
• Most important structure in Midbrain is
the Reticular
Formation
– controls arousal (no not that
type of arousal)
If Destroyed
coma
Wide awake
Forebrain
Largest part of the brain
– The most important part
of the brain for this class
– What makes us human.
Made up of 3 parts
– Thalamus
– Limbic System
– Cerebral Cortex.
Thalamus
• The operator / switchboard
of the brain (relay station)
• Any sensory information that comes
into our bodies (sight, hearing, touch
and taste) goes to the Thalamus first
from the spinal cord
– Every sense except smell
• It then sends them to other parts
of the brain to get processed
The Limbic System
Sometimes called the
emotional control
center of our brain
Contains Four Parts
Hypothalamus
Maybe the most important and
powerful structure in the brain
– Only the size of a pea
Controls and regulates vital body
functions
• Body temperature
• Sexual Arousal
• Hunger
• Thirst
Often referred to
as the “pleasure • Endocrine System
center”
Rat with an Implanted
Electrode in the pleasure
center of Hypothalamus
Hippocampus
• Involved in the
processing and
storage of memories.
– Not stored here, but
it helps put them in
the right places
Amygdala
• Handles emotional response
to fear and aggression
• Also involved in handling basic
emotions like anger and jealousy
Pituitary Gland
• “Master Gland”
• Responsible for the production and
distribution of hormones
The Cerebral Cortex
• The most important part of
the brain – “makes us human”
• Made up of densely packed
neurons often called “gray
matter”
• It is big and full of wrinkles
called fissures.
• If I took out your cerebral
cortex and ironed it, it would be
as big as a large pizza (but would
not taste as good)
The Cerebral Cortex is divided into two hemispheres
Lateralization:
•Division of functions
between sides of the brain
•right controls left
and vice versa
•Often one side is better
at certain tasks than
The other side
In general =
Left Hemisphere: language abilities –speaking, reading, writing
logical analysis - math
Right Hemisphere: understanding spatial relationships –
puzzles, reading maps = recognizing faces and interpreting
facial expressions and perceiving and expressing emotion
= likes art and music
Looking at the nose…
Smiling or Frowning???
Between the two hemispheres is a band
of nerve fibers called the Corpus
Callosum
Divides the 2
hemispheres.


Corpus Callosum
Helps the two sides communicate
with each other


Sometimes this has to be removed
(usually seen in people with epilepsy)
Sometimes a whole side of the brain
has to be removed
• hemispherectomy
They are then called Split Brain
Patients


They actually have two separate
brains in their heads, and one brain
has no idea what the other is doing
However, through plasticity most sbp
will find ways to get their
hemispheres to communicate
Testing the Divided Brain
Sperry and Gazzaniga
– tested split brain patients
 For
For Example
most people the ability to see comes
from the left hemisphere (which controls
the right field of vision)
 So
if a sbp sees an elephant in their left
visual field they will not be able to say what
they see, but they can write it with their
right hand (but not the left hand) – get it??
Split Brain Patients
Decreasing Left-handers
Areas of the
Cerebral Cortex
The Brain’s Thinking, Calculating,
Organizing, and Creative Center
The Cerebral Cortex is made up
of four Lobes.
REMEMBER!! We actually have 8 lobes!!
Frontal Lobe
Top part of our brain
behind our eyes
• Higher mental functions
– thinking, planning, problem
solving, decision making, and
accessing memories
• Motor Cortex
– sends signals to our body
controlling voluntary muscle
movements
– Damage this area and you may
not be able to move certain
parts of your body
Parietal Lobe
• Located in back of the
frontal lobes on the top of
our head
• Contains Sensory Cortex
– Process information relating
to sensations of touch,
pressure, temp. and pain
– Damage this area and it may
result in an inability to
integrate sensations
Motor and Sensory Cortexes
Homunculus
Occipital Lobe
• Located in the very
back of our brain
• Deals with vision.
• Contains Visual Cortex
– interprets messages from
our eyes into images we
can understand.
• Get hit here and you
may “see stars”
Temporal Lobe
• Located just above our ears on both
sides of our head
• Contains the Auditory Cortex
• Process sound sensed by our ears
• NOT LATERALIZED – What??
Brain Activity when Hearing, Seeing,
and Speaking Words
Two Other Areas To Know
Broca’s Area
 Responsible for transferring
thoughts into audible spoken
words
• Damage to Broca’s Area is called Broca’s
Aphasia: unable to make movements to
talk.
Wernike's Area:
– Responsible for transforming
spoken words into thoughts
• Wernike's Aphasia: unable to understand
speech
Association Areas
• Any area NOT associated with receiving sensory
information or coordinating muscle movements.
– But has some higher level purpose
• We are not so concerned with association areas
– But it does make up most of the cerebral cortex
Specialization and Integration in Language
How do we read and recite??
Parts of the brain!
• Pinky and the Brain
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