Transcript Chapter 3: The Brain

Do Now: Is the dancer turning
clockwise or counter clockwise?
Put your
right hand
in the air
Point
palm
downward
Put your
right
finger on
your ear
Say “This
is my
favorite
ear”
What your brain just did…
Analyzed instructions to lift
right hand
Triggered emotions in midbrain…”Is she nuts?” “Why
are we doing this?”
Sent to speech area to say
the words
Put words together into
sentence
Called on area that
controls hand movements
in left part of your brain
Called on area that
controls hand movements
(your finger did not end up
in your eye or nose!)
Searched memory bank for
words you needed
What does the brain look like?
• Tightly compressed
macaroni
• Studying uses more
energy than jogging
• Uses 20% of your
oxygen
• Is protected in multiple
ways.
Where does the brain sit?
Central Station of
Human Nervous System
CNS (Central Nervous
System)
Floats in cerebrospinal
fluid
Enclosed in the cranium
Most common damage:
stroke, blunt head
trauma
Corpus Callosum
Broad, thick band
running from side to
side and consisting
of millions and
millions of nerve
fibers.
Connections
between left and
right sides of brain.
Highway of
information – it is the
Newburgh-Beacon
Bridge of the I-84 of
your brain!
Upper Brain
Mid Brain
Lower Brain
Brain Stem
You have inherited 1,000,000 dollars!
Congratulations! You are moving to new
house you are having made and have to
pack your things in boxes.
1. How will you pack your priceless
glassware that Aunt Edna left you in her will
to make sure they don’t break? If any of
them break, the money has to be given to a
distant cousin. Describe in a few sentences
how you will pack the glasses?
How is the brain protected?
• Protected by the thick
bones of the skull
• Cerebral Cortex covering
• Suspended in
cerebrospinal fluid
• Isolated from the
bloodstream by the
blood-brain barrier a
semi-permeable
membrane that protects
the brain.
• The delicate nature of the
human brain makes it
susceptible to many types of
damage and disease.
• Infection of the brain is rare
because of the barriers that
protect it, but is very serious
when it occurs.
• Multiple Sclerosis-mylen,
insulation for nerves, is
impaired.
• Parkinson’s Disease,
Huntington’s Chorea = CNS
diseases
What is the Upper Brain?
• Cerebral Cortex: outermost layer of brain covers the
cerebrum – gray matter.
• Higher level thought
• It is the most highly developed part of the human brain
• responsible for thinking, perceiving, producing and
understanding language.
Phineas Gage: Neuroscience’s Most Famous Patient
Why is the cerebral cortex so
important?
• Personality: makes us “human”
• “Seat of the soul”
• Example: when faced with severe brain injury
to frontal lobe– personality sometimes
changes completely
• Strokes, tumors – sometimes causes this
What does the mid brain do?
Mid Brain
Limbic
System
Emotions
Sexual
instincts
Sense of
smell
Possible connection?
What does the lower brain do?
Lower
Brain
reaction
primal
aggression
Cerebral cortex: covers brain (gray matter)
Fissure: groove along middle of brain
Parietal Lobe: sensory strip
Motor Strip: along frontal lobe - movement
Temporal Lobe: speech, hearing
Prefrontal Lobe:
:personal
memories
Occipital Lobe:
interprets visual
information
Frontal Lobe::reasoning, personality,
Cerebellum: balance, Reticular Activating System:
Thought, complex thoughts
alertness
coordination
Hemispheres
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Brain divided into two sides
Fissure: groove along center
Right: controls left
Left: controls right
Right Brain or Left Brain?
1. What is the cerebral cortex responsible for?
2. What is brain dominance theory?
3. Left Brain?
4. Right Brain?
5. What is the Newburgh Beacon Bridge of the I84 of your brain?
6. What is your lower brain and brain stem
responsible for?
Cerebral cortex: covers brain (gray matter)
Fissure: groove along middle of brain
Parietal Lobe: sensory strip
Motor Strip: along frontal lobe - movement
Temporal Lobe: speech, hearing
Prefrontal Lobe:
:personal
memories
Occipital Lobe:
interprets visual
information
Frontal Lobe::reasoning, personality,
Cerebellum: balance, Reticular Activating System:
Thought, complex thoughts
alertness
coordination
What is a stroke?
•
A stroke is a medical emergency. Strokes happen when blood flow to your brain stops. Within
minutes, brain cells begin to die. There are two kinds of stroke. The more common kind,
called ischemic stroke, is caused by a blood clot that blocks or plugs a blood vessel in the
brain. The other kind, called hemorrhagic stroke, is caused by a blood vessel that breaks and
bleeds into the brain. "Mini-strokes" or transient ischemic attacks (TIAs), occur when the
blood supply to the brain is briefly interrupted.
Symptoms of stroke are
• Sudden numbness or weakness of the face, arm or leg (especially on one side of the body)
• Sudden confusion, trouble speaking or understanding speech
• Sudden trouble seeing in one or both eyes
• Sudden trouble walking, dizziness, loss of balance or coordination
• Sudden severe headache with no known cause
• If you have any of these symptoms, you must get to a hospital quickly to begin treatment.
Acute stroke therapies try to stop a stroke while it is happening by quickly dissolving the
blood clot or by stopping the bleeding. Post-stroke rehabilitation helps individuals overcome
disabilities that result from stroke damage. Drug therapy with blood thinners is the most
common treatment for stroke.
NIH: National Institute of Neurological Disorders and Stroke
Do Now:
Make a happy face
Make an angry face
Make a sad face
Make a fearful face
How do you know how to do that?
Face Blindness Test
Do Now:
This is a G rated activity–
touch the area where your corpus callosum
(under the fissure) is
Now touch your frontal lobe.
Now your Parietal lobe
Now your Temporal lobe
Now your Occipital lobe
Now your Cerebellum
Now your Medulla Oblongata
Summary
There are three parts to the brain on a horizontal level
• Upper Brain: higher level thinking
• Mid Brain: (Limbic System)vision, hearing, motor
control, sleep/wake, arousal (alertness), and
temperature regulation
• Lower Brain: primitive functions, aggression, fight or
flight
• Brain Stem: autonomic functions
• Two hemispheres – right hemisphere controls left, left
hemisphere controls right
• Brain Dominance Theory: Right brain dominant – art,
language, creative. Left brain – logical, math, organized
Do Now: Draw a Clock
Mini-cog
During the mini-cog, a
person is asked to complete
two tasks:
1. Remember and a few
minutes later repeat the
names of three common
objects
2. Draw a face of a clock
showing all 12 numbers in
the right places and a time
specified by the examiner
3. The results of this brief test
can help a physician
determine if further
evaluation is needed.
Mini-mental state exam (MMSE)
During the MMSE, a health professional asks a patient a series of questions designed to
test a range of everyday mental skills.
1.
2.
3.
4.
5.
6.
7.
8.
Examples of questions include:
Remember and repeat a few minutes later the names of three common
objects (for instance, horse, flower, penny) (5)
State the year, season, day of the week and date 5)
Count backward from 100 by 7s or spell "world" backwards (3)
Name two familiar objects in the office as the examiner points to them (5)
Identify the location of the examiner's office (state, city, street address,
floor) (3)
Repeat a common phrase or saying after the examiner (2)
Copy a picture of two interlocking shapes (1)
Draw this (6)
Name the three objects from
earlier.
Any score greater than or equal to 25 points (out of 30) is effectively normal
(intact). Below this, scores can indicate severe (≤9 points), moderate (10-20
points) or mild (21-24 points) cognitive impairment.[9] The raw score may also
need to be corrected for educational attainment and age.[10] Low to very low
scores correlate closely with the presence of dementia,
AD caused by Amyloid Plaques
• Researchers found that healthy test subjects
were able to list 20 to 25 words in each test,
but patients with Alzheimer's could remember
only 10 to 15 words.
• The Alzheimer's patients were unable to
remember words learned later in life but
could remember words learned in early
childhood. This pattern was so consistent that
researchers were able to determine which
subjects had Alzheimer's based on this word
loss.
What are some other parts of their
brain and their purpose?
Brain stem: internal physical state of body
Medulla Oblongata: breathing, heartbeat
Pons: regulates brain during sleep
Thalamus: relay station between senses and
cerebral cortex
Cerebellum: balance and movement
Limbic system: emotions, memory
Hippocampus: long term memory
Amygdala: aggression, emotion, motives, (very
active during adolescence)
Hypothalamus: eating, drinking, body temperature
Disorders of the Brain
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Attention Deficit Disorder
TBI: Traumatic Brain Injury
Alzheimer’s Disease
Dementia with Lewey Bodies:
Although, where Alzheimer’s disease usually
begins quite gradually, DLB often has a rapid
or acute onset, with especially rapid decline in
the first few months.
Exit Quiz
• What is the Newburgh-Beacon Bridge of the
Interstate 84 of your brain called?
• What does it mean if a neurologist asks you to
“Draw a Clock”?
• What rare and controversial procedure is
sometimes done to patients with severe
seizure disorders?
What are Neurons?
Neurons
Cell body
DNA
Mitochondria
Axons
Long cable-like
Carries nerve impulse
on length of cell
Dendrites
Branches connect to
communicate with other cells
Located at either end of cell
Myelin
Thin covering over nerve
Like insulated
electrical wire
Myelinated neurons are found in the peripheral nerves (sensory and motor neurons),
while non-myelinated neurons are found in the brain and spinal cord.
Sensory Neurons: Travel from body to brain
Motor Neurons: Travel from brain to body
Interneurons: Connect sensory and motor
neurons
Receptors; Put information into
electrical/chemical messages to be transmitted by
sensory neurons
The Role of Neurons in your Brain
I travel from
body to
brain
I travel
from brain
to body
Receptors
Motor
Neuron
Sensory
Neuron
Receptors
What he
said….
We put information
into electrochemical
messages
transmitted by
sensory neurons
Inter
Neuron
I connect sensory
and motor
neurons
http://learn.genetics.utah.edu/content/addiction/reward/madneuron.html
Synapses, neurotransmitters,
neurons…oh my!
Neuron
Synapse
Neurotransmitters
• Gather and transmit
electric and chemical
signals
• Point where 2 or
more neurons
connect, (pass info)
• Signals travel up to
several feet
• Chemicals in the
endings of nerve cells
that send information
across synapse
• This neuron travels from your
brain to your body?
• This neuron travels from your
body to your brain?
• These neurons help neurons
connect to each other to get to
their source?
• What is the insulation covering
your peripheral nerves called?
• What disease is caused by an
autoimmune reaction which
causes a deterioration of this
insulation?
What are Neurotransmitters made up of?
Dopamine
Acetylcholine
Endorphin
Motor Functions
Too much – Schizophrenia (theory)
Too little – Parkinson's and other
movement diseases
Attention and R.E.M. Sleep Inducer (RAS)
Too little: Myasthenia Gravis (muscle
weakness)
Alzheimer’s Link
Relieve pain, increase wellbeing
Natural form of morphine (woo hoo!)
Serotonin
chemical that helps maintain a "happy
feeling," helps with sleep, anxiety,
depression
GABA
gamma-aminobutyric acid
amino acid that helps induce relaxation
and sleep builds muscle tone.
It balances the brain by inhibiting overexcitation
Reuptake
• The main objective of a Reuptake Inhibitor is
to substantially decrease the rate by which
neurotransmitters are reabsorbed, leaving a
gain
large
in the concentration of
neurotransmitter in the synapse.
• Example: Antidepressant drugs often use
ssri’s (selective serotonin reuptake inhibitors)
to cause a GAIN in amount of serotonin in
brain.
Drugs don’t ADD chemicals into your brain as
much as they change the INTERACTION of
your existing brain chemistry
How Antidepressants Work
• Most antidepressants are believed to work by
slowing the removal of certain chemicals from the
brain. These chemicals are called neurotransmitters
(such as serotonin and norepinephrine).
Neurotransmitters are needed for normal brain
function and are involved in the control of mood and
in other functions.
• Antidepressants work by making these natural
chemicals more available to the brain.
Reticular Activating System
• Keeps us alert or puts us to sleep – alcohol
mimics reticular system neurons
The reason that
most drunk driving
accidents are due
to drivers falling
asleep at the wheel
What did we learn?
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Why do people have split brain surgery?
What is Myelin:
Where to Motor Neurons travel?:
Where do Sensory Neurons Travel
What do Interneurons do?
What do Receptors do?
receive neurotransmitters
What are Neurotransmitters?
electrical/chemical messages passed along by neurons
What is Serotonin?
What is Dopamine known for?
Serotonin Overdose
Class
Drugs
5-HT1 agonists
Monoamine oxidase
inhibitors (MAOIs),[1] TCAs,[1] SSRIs,[1] SNRIs,[1]
bupropion,[6] nefazodone,[7] trazodone[7]
tramadol,[1] pethidine,[1] fentanyl,[1] pentazoci
ne,[1] buprenorphine[8]oxycodone,[9] hydrocod
one[9]
phentermine,[10] diethylpropion,[10] amphetam
ine,[3][10] sibutramine,[1]methylphenidate,[10] m
ethamphetamine,[10] cocaine[10]
triptans[1][10]
Psychedelics
Ecstasy Crystal Meth Meth] LSD[11][12]
Antidepressants
Opioids
CNS stimulants
Herbs
Others
St John's Wort,[1] Syrian rue,[1] Panax
ginseng,[1] Nutmeg[13]
tryptophan,[1] LDopa,[14] valproate,[1] buspirone,[1] lithium,[1] li
nezolid,[1][15]dextromethorphan,[1] 5hydroxytryptophan,[7] chlorpheniramine,[10] ris
peridone,[16]olanzapine,[17] ondansetron,[1] gra
nisetron,[1] metoclopramide,[1] ritonavir[1]
Exit Quiz
Exit Quiz
• Look closely into the eyes of your closest
classmate
(don’t worry…it’s not romantic)
Now keep looking……
Pupillary Response
What are reflexes?
•A reflex is an involuntary or automatic,
action that your body does in response to
something - without you even having to think
about it.
• There are many types of reflexes and every healthy
person has them. In fact, we're born with most of
them…and most of them fade by age 6 months.
•Some infant reflexes that show up in adulthood can
be signs of neurological disease.
Why do we have reflexes?
• Reflexes protect your body from things that can
harm it.
• For example, if you put your hand on a hot stove, a
reflex causes you to immediately remove your hand
before a "Hey, this is hot!" message even gets to
your brain
• Other examples of protective reflexes are blinking
when something flies toward your eyes or raising
your arm if a ball is thrown your way. Even coughing
and sneezing are reflexes. They clear the airways of
irritating things
What are the reasons for reflexes?
• Protective
• Survival Instinct?
• Reflexes take place without traveling from
brain (motor neurons) to sensory neurons
How are reflexes different than reactions?
They originate from your spinal cord…
there are no thought processes involved.
How would this relate to REACTION time…say
when texting while driving?
Common Reflexes
Babinski
(foot)
Moro
(startle)
Tonic
(fencing)
Rooting
(sucking)
Pupillary
(eyes – constriction
Or dilation)
Galant
(leaning against
side of spine
that is stroked)
Gag Reflex
Scratching Reflex
Blinking Reflex
Babinski Reflex
• Babinski's reflex occurs when the big toe
moves toward the top of the foot and the
other toes fan out after the sole of the foot
has been firmly stroked.
• This reflex, or sign, is normal in younger
children, but abnormal after the age of 2
• The presence of a Babinski's reflex after age 2
is a sign of damage to the nerve paths
connecting the spinal cord and the brain
Babinski on Infant
Babinski Explanation
Moro Reflex
• Arms will rapidly fan out as if startled.
• It is normally present in all infants/newborns
up to 4 or 5 months of age
• Absence indicates a profound disorder of the
motor system.
• Persistence of the Moro response beyond 4 or
5 months of age is noted only in infants with
severe neurological defects
• It is believed to be the only unlearned fear in
human newborns
Moro
Tonic (Fencers) Reflex
• Known as the “fencing reflex" because of the
characteristic position of the infant's arms
and head, which resembles that of a trained
fencer.
• Beyond the first months of life may indicate
that the child has developmental delays, at
which point the reflex is atypical or abnormal.
For example, in children with cerebral palsy
the reflexes may persist and even be more
pronounced.
Tonic
Knee Jerk or (DTR) reflex
• The reflex that the doctor checks by tapping
your knee is called the patellar, or knee-jerk,
reflex. It is also known as a deep tendon reflex
(DTR) This tap stretches the tendon and
the muscle in the thigh that connects to it.
• A message then gets sent to the spinal cord
that the muscle has been stretched. The spinal
cord very quickly sends a message back to the
muscle telling it to contract. The contraction
of the muscle causes your lower leg to kick
out.
Knee Jerk (Patellar) Reflex
Causes of Abnormal Knee Jerk Response
• Hyperactive (knee jerks too much): ALS, brain
tumor, stroke, liver disease, hypocalcemia (low
calcium), hypomagnesemia (low magnesium),
hypothermia, multiple sclerosis, preeclampsia,
spinal cord lesion and tetanus.
• Hypoactive (knee doesn't jerk enough):
botulism, nerve inflammation, peripheral
neuropathy, polio, untreated syphilis,
diabetes, alcoholism, arthritis, etc.
• Most common reason: it is what it is!
What have we learned?
• What is a reflex?
• A reflex is an involuntary or automatic, action that your body does in
response to something - without you even having to think about it.
• Why do we have reflexes?
• Reflexes protect your body from things that can harm you
• How are Reflexes different from reactions?
• They use inter-neurons to communicate without direct motor neurons
• What would having a infantile reflex as an adult mean?
• They are often a sign of neurological disease
• What type of neurons do reflexes use?
• Interneurons….without the need for sensory or motor neurons
What else did we learn?
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What is the Moro Reflex?
A startle response in infants
When would you NOT want to see a positive Babinski reflex?
In an adult
What is HYPO active?
Less response
What is HYPER active?
Too much response
What is a Tonic reflex?
Infant poses in characteristic “fencing” pose when head is
turned to side.
Wrap Up
Reading: What are reflexes?
1. Read article
2.
3.
Answer questions: How does a DTR work in terms of
muscles and spinal cord communication?
Why do we even have a DTR?
What have we learned?
• Cerebral Cortex – covers your brain, gray matter
• Hemispheres-each half of the brain that has different roles.
Hemisphere dominance is a theory…what do you think?
• Corpus Callosum: The Newburgh Beacon Bridge of the
Interstate 84 of your brain
• Frontal Lobe: reasoning, higher level thought processes
• Parietal Lobe: motor strip, sensory strip
• Temporal Lobe: hearing, speech
• Occipital Lobe: sight
• Medulla: autonomic functions
• Cerebellum: balance, coordination
• Pons and RAS: sleep, recognition of faces
• Prefrontal lobe: seat of the soul, personal memories
Headaches
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Vascular Headaches: Migraines
Muscle Headaches: Cluster, Tension
Worst Headache of your life! – aneurism
Seizures: Grand Mal, Petit Mal, Absence
• Lower brain: primitive reactions
• Midbrain: smell, emotion (limbic system)
• The blood brain barrier protects your brain from
infection
• Myelin: fatty sheath that covers nerves similar to an
electrical wire – lesions can cause neurological
symptoms
• Right Brain/Left Brain Theory (R=holistic L= analytical
• Neurons: Motor = brain to body, Sensory = body to
brain, Interneuron=connections between nerves,
Receptors=receive neurotransmitter
• Neurotransmitters: electrical/chemical
messages passed along by neurons
• Serotonin: happy chemical
• Dopamine: movement
• Acetylcholine: sleep, attention
• Endorphins: natural morphine
• Types of reflexes: Knee Jerk, Babinski, Moro,
Fencers (Tonic)
• Primitive reflexes in adulthood often sign of
neurological disease
• Normal adult reflexes protect us.
Exit Quiz
Do Now
• Why do we have reflexes?
• Describe two reflexes you have now
• Describe one reflex you don’t have anymore
and why
Dr. Oliver Sacks
In 1966 Dr. Sacks began working as a consulting neurologist
for Beth Abraham Hospital in the Bronx, a chronic care
hospital where he encountered an extraordinary group of
patients, many of whom had spent decades in strange,
frozen states, like human statues, unable to initiate
movement. He recognized these patients as survivors of
the great pandemic of sleepy sickness that had swept the
world from 1916 to 1927, and treated them with a thenexperimental drug, L-dopa, which enabled them to come
back to life.
They became the subjects of his book Awakenings, which
later inspired a play by Harold Pinter ("A Kind of Alaska")
and the Oscar-nominated feature film ("Awakenings") with
Robert De Niro and Robin Williams. Dr. Sacks is a NYT
bestselling author and award winning Neurologist. You can
reach him at www.oliversacks.com
This film is based on a true story
Wrap Up Questions Day 1
1. What do the other doctors think Lucy’s catching
the ball is?
2. What is the difference between a reflex and a
reaction?
3. In reference to neuron activity – why would the
fact that this is a “reaction” rather than a reflex
mean for the patient?
4. How does Dr. “Sacks” convince the staff to consider
these patients more than just the “garden”?
5. Which patient does he focus on first and why?
The Film will be the essay portion of the Midterm Friday.
Awakenings Day 3 Questions
1. How do they create a field of vision for Lucy to walk
to the water fountain?
2. When does Dr. Sayer realize that “they are alive
inside…it’s what I know, what I believe.”
3. What is significant about the book about the
panther?
4. What is the drug he decides to try on Leonard?
5. What is this drug initially designed for – and why
does he believe it might work for the postencephalitis patients?
The Film will be the essay portion of the Midterm Friday.
Do Now: Awakenings – final day
• In reality, Dr. Sacks was conducting a double blind study
with 50% of the group on the L-Dopa and the rest on a
placebo. When Dr. Sacks saw the respons, he
immediately put the entire group on the drug. The
family members had to sign approvals releasing the
hospital from responsibility. Do you think this was
ethical? Why/Why not?
• Even though Dr. “Sayer” was the doctor and Leonard
was the patient – do you think he learned anything
from Leonard. Do you think it would’ve been better for
the patients to remain in their frozen states rather than
giving them back life for only a summer?
Midterm
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Neuroscience Test – Midterm
Notes: Online and Review Sheet
Today: Intro to Awakenings – Thurs.
Fri. begin Midterm
Mon. Midterm (end) Awakenings
Midterm Review
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Introduction to Psychology
Psychological Approaches and Modalities
Famous Early Psychologists
Freud and his Theory of Personality & Psychosexual Stages of Development
• Research Methods & Ethics
• Neuroscience Unit
“Born on a Blue Day”
Take out your notebook and write down these
questions:
• What is Daniel Tammet’s ability?
• What is synesthesia?
• What other neurological disorder does Daniel
have and how does it limit his life?
• How does it enrich his life?
• Who did he meet….?
Do Now: Awakenings Day 1 Questions
1. What are Leonard’s first symptoms?
2. What is Dr. “Sacks” real job description?
3. What is his reaction to Bronx Chronic
Hospital?
4. What do you notice about the “statues”?
5. How do the staff treat these patients?
The Film will be the essay portion of the Midterm Friday.