Transcript Too little

10/8 AP Psych Class Announcements:
Test or vocab quiz make-up:
Shaniya, Madeline,
Brooklyn,
Aim: to discuss the
functions of the nervous
system categories, label
the parts of the brain
Do NOW: “The Science of
Love”
Turn in article
HW: Bring Playdough!!
Help class Wed after
school
10/11,14 AP Psych Class Announcements:
Test or vocab quiz make-up:
Aim: explain functions of
various parts of the brain
Do NOW: none
Turn in article answers
HW: practice questions
Study for test
Turn in ch 2 notecards
The Biology of Mind
Chapter 2
Ways we Study the Brain
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Accidents
Lesions
EEG
CAT Scan
PET Scan
MRI
Functional MRI
Accidents
Phineas Gage Story
• Personality changed
after the accident.
What does this tell us?
• Answer: Different
parts of the brain
control different
aspects of who we
are!!!!!
Phrenology
• Early attempt to study
the brain
• Franz Gall
• He tried to “map” out
the brain with
corresponding
personality traits.
• They were identified by
feel the bumps on your
head
Lesions
• Purposeful
removal or
destruction of
some part of the
brain.
Electroencephalogram
• EEG machine
• Detects brain waves
through their
electrical output.
• Used mainly in sleep
research.
Computerized Axial Tomography
• CAT Scan
• 3D X-Ray of the
brain.
• Good for tumor
locating, but
tells us nothing
about function.
CT example
Magnetic Resonance Imaging
• MRI
• More detailed picture
of brain using
magnetic field to
knock electrons off
axis.
• Takes many still
pictures (slices)and
turns images into a
movie like production.
• Does not study
function!
MRI example
• Notice the tumor…
Positron Emission Tomography
or PET Scan
• Measures how much of a chemical the brain is using (usually
glucose consumption). Patient drinks a radioactive sugar
which show up when certain parts of the brain are being
used.
• Good for studying function!!
PET scan
• Depression
Functional MRI
• Combination of PET and MRI
• fMRI is good for function, hence the f.
The Biology of Mind
I. Neural Communication
 Neurons
 How Neurons Communicate
 How Neurotransmitters Influence Us
II. The Nervous System
 The Peripheral Nervous System
 The Central Nervous System
III. The Brain
Neural Communication
Neurobiologists and other investigators
understand that humans and animals operate
similarly when processing information.
Note the similarities in the above brain regions, which are all
engaged in information processing.
Neural and Hormonal Systems
Will Explain Why We FEEL……
Nervous
Strong
Pain
Sick
Neuroanatomy
Synapse
Neurotransmitters (chemicals held in terminal
buttons that travel through synaptic gap)
Synapse
Parts of a Neuron
Cell Body: Life support center of the neuron.
Dendrites: Branching extensions at the cell body.
Receive messages from other neurons.
Axon: Long single extension of a neuron, covered with
myelin [MY-uh-lin] sheath to insulate and speed up
messages through neurons.
Terminal Branches of axon: Branched endings of an
axon that transmit messages to other neurons.
Parts of a neuron:
• http://learn.genetics.utah.edu/content/addict
ion/reward/madneuron.html
1. Resting potential……
• Draw the axon membrane at
resting potential
Na+ (sodium) is outside the membrane
K+ (potassium) is inside the membrane too, but
a mainly negative charge exists INSIDE the
membrane.
Polarized
• At resting potential, we say the cell is
polarized, that is, the + and – charge are at
opposite position (one is in the membrane,
one is outside).
2. Threshold
Threshold: Each neuron receives
excitatory and inhibitory signals from
many neurons. When the excitatory
signals minus the inhibitory signals
exceed a minimum intensity (threshold)
the neuron fires an action potential.
Gas vs. brake pedals of a car!!!!
3. Action Potential
4. Depolarization
Action Potential-if
threshold is reached,
process of firing begins.
Gates open and Na+ ions
begin moving in and out of
the axon
Depolarized- during
action potential when
the ions are moving in
and out.
Action Potential
A neural impulse. A brief
electrical charge that
travels down an axon and
is generated by the
movement of positively
charged atoms in and out
of channels in the axon’s
membrane.
5. Refractory
• Refractory period- for
a short time (before the ions
can return to original
position) the neuron can’t
fire again immediately
• Ex: when you flush a
toilet, you can’t flush
again immediately
6. Repolarize
• The ions must go back
to original position to
be ready to fire again.
• EX: This is like when
the toilet bowl is filling
up with water
The All-or None Response
• The idea that either the
neuron fires or it does
not- no part way firing.
• Again, you can’t
“kinda” flush a
toilet!!
Review
• Put the following events in their proper order
transmission to your “Study Buddy” :
• Refractory
• Depolarized
• Resting potential
• Action potential
• repolarize
• Threshold
• Excitatory vs. inhibitory signals
• polarized
How does the brain perceive
intensity, like pain?
By the number of times the neuron
fires!!!!!!
How does the process create an electrical
charge?
The transfer of ions crossing the axon’s
membrane causes an electrical charge.
Review:
How does a Neuron fire?
• 1. Resting Potential: the neuron
before it fires- is polarized
• 2. Threshold reached- more
excitatory than inhibitory signals
• 3. action potential begins
• 4. axon is depolarized – ions
move in and out
• 5. refractory/repolarizationreloading of ions- filling up the
toliet bowl
So….how do nerve cells
communicate?
• Do nerve cell touch
each other and send
the electrical charge to
each other?
• No!! They do not touch!
• How would they know
what “message” to
send?
• So…how does each cell
communicate across a
gap?
• They are separated by a
tiny gap.
At the Synapse
Synapse [SIN-aps] a junction between the axon
tip of the sending neuron and the dendrite or
cell body of the receiving neuron. This tiny gap
is called the synaptic gap or cleft.
Neurotransmitters
Neurotransmitters
(chemicals) released from
the sending neuron travel
across the synapse and bind
to receptor sites on the
receiving neuron, thereby
influencing it to generate an
action potential.
They fill in receptor sites
like keys to a key hole.
Lock & Key Mechanism
Neurotransmitters bind to the receptors of the
receiving neuron in a key-lock mechanism.
Reuptake
Neurotransmitters in
the synapse are
reabsorbed into the
sending neurons
through the process of
reuptake. This process
applies the brakes on
neurotransmitter
action.
Reuptake demonstration
• http://www.thirtee
n.org/closetohome
/animation/cocaanim-main.html
• Neurotransmitters
to know:
• 1.Dopamine
• 2. ACH
• 3. serotonin
• 4. endorphins
• 5. glutamate
• 6. GABA
What is an SSRI?
• Selective Serotonin Reuptake Inhibitor
• Prozac, Zoloft, Celexa etc…..
• These are anti-depressants that block the
reuptake of serotonin, therefore, making sure
the synapse is filled with serotonin
How is a neural transmission both an
electrical and a chemical response?
• Electrical- action potential create electricity
• Chemical- at the synapse
1. Acetylcholine (ACH)
• Deals with motor
movement and
memory.
• Lack of ACh has
been linked to
Alzheimer’s disease.
2. Serotonin
It’s pathways are
involved with mood
sleep and hunger.
Too little: depression
Too much: mania
From Mapping the Mind, Rita Carter, © 1989
University of California Press
3. Dopamine
• Its function is:
motor movement, pleasure and alertness.
Too little: dopamine
is associated with
Parkinson’s disease.
Too much : is
associated with
schizophrenia.
Norepinephine
• Chemically the same as adrenaline
• Controls alertness and arousal
• Too little: depression
4. Endorphins
• Function deals with pain
control.
We become addicted
to endorphin causing
feelings.
5. GABA
• an inhibitory neurotransmitter
• Too much: you become sedate, drowsy
• Too little: anxiety
6. Glutamate
• An excitatory neurotransmitter
Too much: MSG excites neurons, starting
migraines
Too little: memory , concentration problems
Drugs can be…..
• Agonists- mimc and make
neuron fire
• Antagonists- stop neural firing
• Reuptake Inhibitors- block
reuptake
What are agonists and
antagonists?
• Agonists mimic neurotransmitters.
• Ex: Morphine mimics endorphin.
• Antagonists block neurotransmitters:
• Ex: curare blocks ACh (paralyzes you)
Botox blocks ACh
Agonists
Antagonists
Types of Neurons
• Sensory (afferent)
Neurons- from senses
to spinal cord
• Interneurons from
spinal cord to brain
• Motor (efferent)
Neurons-from brain
back to muscles, glands
Neural Chain
What about a reflex?
• Sensory neuron
• Hit knee
motor neuron
motor neuron
to spinal cord
There is no “inter neuron” involved!!!!!!
Nervous System
Central
Nervous
System
(CNS)
Peripheral
Nervous
System
(PNS)
The Nervous System
Autonomic Nervous System (ANS)
Sympathetic NS
“Arouses”
(fight-or-flight)
Parasympathetic NS
“Calms”
(rest and digest)
Central Nervous System
The Brain and Neural Networks
Interconnected neurons form networks in the
brain. Theses networks are complex and modify
with growth and experience.
Complex Neural Network
The Endocrine System
The Endocrine
System is the body’s
“slow” chemical
communication
system.
Communication is
carried out by
hormones
synthesized by a set
of glands.
Hormones
Hormones are chemicals synthesized by the
endocrine glands that are secreted in the
bloodstream. Hormones affect the brain and many
other tissues of the body.
For example, epinephrine (adrenaline) increases
heart rate, blood pressure, blood sugar, and
feelings of excitement during emergency
situations.
Pituitary Gland
Is called the “master gland.” The anterior pituitary
lobe releases hormones that regulate other glands.
The posterior lobe regulates water and salt
balance.
Adrenal Glands
Adrenal glands secretes hormones (epinephrine
and norepinephrine :a.k.a adrenaline) during
stressful and emotional situations
btw: norepinephrine is both a
neurotransmitter and a hormone
•Nervous System
Practice Questions
Answers:
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•
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•
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1. B
2. A
3. C
4. C
5. B
6. A
7. B
8. B
9. A
10. B
11. E
12. A
13. B
14. D
The Brain
Thanks to KAP at www.appsychology.com!
.
The Brain:
Older Brain Structures
The Brainstem is the oldest part of the brain, beginning
where the spinal cord swells and enters the skull. It is
responsible for automatic survival functions.
Brainstem
The Medulla [muhDUL-uh] is the base of
the brainstem that
controls heartbeat and
breathing.
Pons
• Located just
above the
medulla.
• Involved in facial
expressions.
(Pons = yawns)
Reticular Formation
• controls arousal and
ability to focus our
attention.
• Reticular = net (like
pantyhose); opens
during day
• Damage to it results in
If Destroyed
coma
Thalamus
• Switchboard “relay
station” of the brain.
• Receives sensory
signals from the
spinal cord and
sends them to other
parts of the brain.
• Receives info from
every sense except
smell.
Cerebellum
• Bottom rear of
the brain.
• Means “little
brain”
• Coordinates
fine muscle
movements and
balance.
The Limbic System
The Limbic System: our emotional
center!!!!
• The Limbic System is
a doughnut-shaped
system of neural
associated with
emotions such as fear,
aggression and drives
for food and sex.
Hypothalamus
• Maybe most
important structure
in the brain!!!!
Controls
• Sleep
• Eating, drinking
• Pleasure, emotions
The most powerful structure in the brain.
• Body temperature
Rat with an Implanted
Electrode in pleasure center of
Hypothalamus
Reward pathways
• http://bcs.worthpublishers.com/introvtk/play
er/pages/inst_Browes_page.aspx?From=Searc
h&Tab=bPage&SearchTerm=brain&SearchFro
m=Gen
Hippocampus
• Involved in the
processing and
storage of
memories.
• Its proximity to
your emotional
centers explains
why memories
and emotions are
so linked!
Amy G. Dala
• Is a very emotional girl “Drama Queen”
Amygdala
• Brain part
involved in telling
your body to
produce
norepinephrine
(adrenaline)
• More involved in
volatile emotions
like anger and
jealousy.
What would happen to you if your limbic system were
disconnected from you frontal lobe?
• The Phineas Gage
Story
Cerebral Cortex
• The intricate fabric of interconnected
neural cells that covers the cerebral
hemispheres. It is the body’s ultimate
control and information processing center.
• It’s what marks us different from animals!
Features of he Cerebral
Cortex
• Made up of densely
packed neurons we call
“gray matter”
• Glial Cells: support brain
cells.
• Wrinkles are called
fissures.
• It’s divided into 2
hemispheres and 4 lobes!
The Cerebral Cortex is made up
of four Lobes.
Frontal Lobe
• Controls abstract
thought, personality and
emotional control and
planning.
• Developed frontal lobe =
maturity!!!!!!!!!!!!!!!!
• Lobotomies damage
this.
What is the motor cortex?
• Part of the brain in the frontal lobe that tells my body how
to move (like typing this).
http://www.pbs.org/wgbh/aso/tryit/brain/#
What is the sensory cortex?
It’s the part that senses our 5 senses. It’s
In the parietal lobe.
What are Motor and Sensory
Cortexes?
The wires are switched! Right controls left!
The motor cortex is in which lobe?
Parietal Lobes
• Contain Sensory
Cortex: receives
incoming touch
sensations from
rest of the body.
• Most of the
Parietal Lobes are
made up of
Association Areas.
Occipital Lobes
• Think “optical”.
• Contains Visual
Cortex: interprets
messages from our
eyes into images we
can understand.
Temporal Lobes
• Located in the
thumb-shaped area
• Process sound sensed
by our ears.
• Interpreted in
Auditory Cortex.
Specialization and Integration in Language
Language
Aphasia is an impairment of language, usually
caused by left hemisphere damage either to Broca’s
area (impaired speaking) or to Wernicke’s area
(impaired understanding).
Language areas
1. Broca’s – speech “He
broca his tongue and
can’t speak!”
2. Wenicke’s – allows you to
understand what others
are saying
“I don’t understand why Nick
and Jessica broke up”
3. Angular Gyrus – allows to
read in your head
Corpus Callosum
• The “bridge”
between the two
hemispheres
Plasticity
The brain is sculpted by our genes but also by our
experiences.
Plasticity refers to the brain’s ability to modify itself
after some types of injury or illness.
“Practice makes perfect”- the more you practice a
skill, the more the brain changes.
The hemispheres of the brain
Left Hemisphere: logic, sequential and
language tasks .
Right Hemisphere: spatial, creative tasks
and name recognition.
Video: Split brain patient
• https://www.youtube.com/watch?v=RFgtGIL7
vEY
• 10 minutes
Review: Brain Parts
List all the parts of the
brain you would be
using for the
following tasks:
Watching a horror movie
Driving a car
Arguing with someone by text
message