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The Brain and Behavior
McElhaney
Biopsychology= Bio explanation/cause for
behavior. Or Physiological Psychology
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Includes Electro/Chemical processes
Brain Anatomy
The Study of Biological Aspects of
Behavior
Hormonal aspects of behavior
Hemisphere specialization
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Phineas Gage- Frontal Lobe injury
Suffered brain injury that caused changes in his
personality and behavior.
Brain Mapping
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We know about the
brain through
experiments
Where portions of
the brain are
stopped, in order to
identify locals of
control.
What tools do Doctors have in
determining Brain Function?
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EEG
CAT Scan
MRI
PET Scan
Role of Glucose
Tools for Viewing Brain Structure and Activity
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EEG
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Electroencephalogram
measures electrical
currents across the
brain
Measure brain activity
And Location of different
functions
Tools for Viewing Brain Structure and Activity
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CT scan
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Also called a CAT scan
Computerized axial
tomography
X-ray of brain tissue
Shows brain structure
Cross section images
Snapshots of the Brain
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PET scan
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Positron Emissions
Tomography
Patients drinks
radioactive glucose*
and image shows
areas of brain activity
or as it’s working.
*Glucose is the primary fuel
of the Brain as it is working.
More glucose in an area
means brain is working.
Tools for Viewing Brain
Structure and Activity
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MRI
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Magnetic Resonance
Imaging
Exposes brain to
magnetic field
Shows brain structure
Neurons are the basic building blocks
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AKA Nerve Cells – 100 Billion in
brain
Carries and processes information
Connected via Chains of specailzed
information
Activate Muscles & Glands
Non are identical
The Neuron and what it does
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Dendrites= “Tree Roots” receives
and messages from other neurons
Soma – cell body, sends Nerve
Impulses
Axon- Fibrous carrier of impulses
Axon Terminals- end of Axon
Myelin Sheath- insulating body
surrounding the axon
Nerve Impulse- “Firing” of a nerve
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Ions= sodium (Na) Electrical Charged
molecules are in each neuron
Electrical charge of <-70> Millivolts
Threshold = trigger point for sending a
message
Nerve Impulse- will be fired when <-50>
Millivolts are reached =Action Potential
Gates open and allow flow of ions- sodium
goes in Potassium out
Action
Potential
Psych Jeopardy Review
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Choose group of 5 people
Divide Key Terms form reading (part
2 recommended)
Make questions/answers on
flashcards (at least 10)
Play Jeopardy monday
Quiz Thursday:
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Neuron and its components
Nerve Impulse and Action Potential
Synapse
Neurotransmitters
Synapses and Neurotransmitters
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Info is transmitted chemically
Synapse = space between neurons
Between Axon terminals and Dendrites
Neurotransmitter=a chemical released by a
neuron that stimulates nearby neurons and
allows for nerve impulses to be passed
throughout the body
Neurotransmitters are kept in vesicles,
which fuse with the axon terminal’s
membrane and travel into the synaptic cleft,
ready to bind to receptors in the
postsynaptic membrane
What a
neurotransmitter
looks like…
Receptors are found at each end of the neuron- cell body and
dendrite
Neurotransmitters can slow or speed up firing of neuron
There are over 100 transmitter chemicals
Facts and Such.
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Everything you do or feel occurs due to communication between
different neurons, which provide information throughout the nervous
system. Within a single neuron, information travels through electrical
signals, but when information is transmitted from one neuron to the
next neuron, the transmission is considered ‘chemical’.
For two neurons to communicate neurotransmitters (messengers) are
released into the synaptic cleft (an extremely tiny gap between
neurons), where they then move to the next neuron and attach
themselves to locations called receptor sites.
The result is an initiation of electrical current that moves through that
neuron toward the next one. After the neurotransmitter does its
thing, it is either destroyed by other chemicals in the synaptic cleft or
is taken back into its original neuron. This action prevents the
neurons from becoming ‘overstimulated’.
When neurons communicate, the effect can either help or hinder the
next neuron. For example, when a person pays attention to one
conversation and ignores others, the neurons in the brain are
‘listening’ to that information (helping) and ignoring the rest
(hindering). Neurons come in different shapes and sizes, affecting
many other neurons, and can have different numbers of synapses.
Some neurons, called Purkinje cells, may have as many as 100,000
synapses.
Neurotransmitters
 Chemicals
that influence
the firing of nerve cells
 Can “excite”-make firing
more likely
 Or “inhibit” make firing
less likely
Neurotransmitter Function
Acetylcholine
Found at neuromuscular
junction; memory and
learning
Dopamine
Movement, muscle control,
learning, attention, emotions,
and rewards
Serotonin
Sleep, mood, hunger, arousal
Associated Diseases
Alzheimer’s disease (decreased
Ach)
Black widow spider (increased Ach)
Botox (decreased Ach)
Curare (decreased Ach)
Parkinson’s disease (decreased
dopamine)
Schizophrenia (increased dopamine)
Depression (decreased dopamine)
Depression (decreased serotonin)
Anorexia (increased
serotonin)
Sleep disorders
Norepinephrine
Fight or flight response
Depression (decreased NE)
Endorphins
(endogenous opiates)
Pain, emotions
Mimicked by opiates (heroin,
morphine, codeine)
Runners high
Neurostimulation
GABA (gamma
amino-butyric acid)
Hunger and sleep, inhibits
CNS
Alcohol consumption causes an
increase in GABA
Effects of Drugs + Meds on
Neurotransmitters
 Alcohol-
Increases GABA, Increases
Dopamine
 Prozac- Increases Serotonin levels
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Same with Zoloft, Paxil, Celexa, Luvox
 Opiates-
Increases Dopamine,
Mimics Endorphins
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Morphine and heroin
 Nicotine-
Imitates Acetylcholine
Drugs and Neurotransmitters
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Psychoactive medications:
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Imitate
Duplicate
Or blocks Neurotransmitters
Curare = poison
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Prevents Acetylcholine- up take
And causes paralysis
Endorphins
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Endorphins are a group of small proteins
naturally occurring in the brain around
nerve endings that bind to opiate
receptors
Natural opiates produced in the brain
which function as the body’s own natural
painkillers and Elevate mood.
Endorphins respond to morphine
Enkephalins= opiate like neural regulators
relieve pain & stress similar to endorphins
Organization of the Nervous System
Central Nervous System
Peripheral Nervous System
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Controls the voluntary behavior
Carries information to and from the
Central Nervous System
Peripheral nervous system is made up of:
Somatic System
Autonomic System
Sympathetic Branch
Parasympathetic Branch
Peripheral Nervous System
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Somatic System- controls voluntary
behavior
Sense organs and skeletal muscles
Autonomic Nervous System
Sympathetic and Parasympathetic
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Both systems work
together:
Emotional
responses and
Involuntary
behavior
Sympathetic:
“Emergency System”
Fight or Flight
Arouses body for
action
Parasympathetic= quiets body,
returns to lower level of arousal, after emotional event
Vital functions, heart rate, breathing, digestion
Types of Neurons
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Sensory Neurons –
Afferent Neurons
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Inter neurons
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Make up the CNS
Motor Neurons –
Efferent Neurons
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Carry the message from
the sense organs to the
CNS
Carry the message from
the CNS to the muscles
or glands
Remember – SAME
(sensory = afferent,
motor = efferent)
Brain Stem
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Medulla– where
spinal cord meets the
skull; controls
heartbeat and
breathing
Reticular
formation– bundle of
nerves running
through the
brainstem; controls
arousal and attention;
filters incoming stimuli
and relays important
information to the
brain.
Cerebral Cortex
Controls information
processing; wrinkled
to increase surface
area
Composed of 8 lobes
(4 on each side)
Corpus Callosum
bundle of nerves
connecting the left
and right
hemispheres
Parietal Lobes
Located on the top and
rear of head
Contains the sensory
cortex (part of
brain that registers
and processes
tactile information
(phantom limb)
Contains the angular
gyrus (left
hemisphere only)
which is involved in
converting written
words into sound
Frontal Lobes
Located in the forehead
region
Includes the motor
cortex (part of brain
that controls
voluntary movement)
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Includes Broca’s
area (needed for
forming words;
located in left
hemisphere only)
Association
areas in this
region – judgment,
planning,
processing new
memories
Occipital Lobes
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Located in the
back of the head
Contains the
visual cortex
Temporal Lobes
Located on the sides of
head, above ears
Receives and processes
auditory
information
Includes Wernicke’s
area (left
hemisphere only) part of brain
involved in
understanding
language
Cerebellum
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Controls balance
and coordination
In the rear of the
head, behind the
brainstem
Thalamus
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Pair of egg-shaped
organs above the
brainstem;
receives
information from
the senses
(EXCEPT FOR
SMELL) and relays
it to the rest of the
brain.
Thalamus
Limbic System
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Amygdala – two
almond shaped
structures; influence
fear and aggression
(monkeys and cats)
Hypothalamus –
below the thalamus;
regulates hunger,
thirst, body temp,
sex, fight-or-flight;
triggers the pituitary
(the “master gland”);
reward center
Hippocampus –
behind the amygdala;
memory
The Brain
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Gray matter – areas
of the CNS with high
concentrations of cell
bodies; outer surface
of cerebrum (cerebral
cortex)
White matter –
areas of the CNS with
mostly myelinated
axons; inner part of
cerebrum
Glial cells – cells in
the brain that nourish
and protect neurons
Name that brain part