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Biological Bases of Behavior
Chapter 3
What’s In This Chapter?
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What does biology have to do with our behavior?
What’s in a brain?????
How does the brain tell the body what to do?
How does the body let the brain know what it’s doing?
Can your brain do things without the body?
Can your body do things without the brain knowing it?
The Brain
 Lesion
 tissue destruction
 a brain lesion is a
naturally or
experimentally
caused
Phineas Gage
Show music video
How we Investigate the Brain
Electroencephalogram (EEG)
 an amplified recording of
the waves of electrical
activity that sweep across
the brain’s surface
 these waves are measured
by electrodes placed on the
scalp
How we Investigate the Brain
• Electrical Stimulation of the Brain (ESB)
– Mostly used with research on animals & some human brain
surgery
– Weak electrical currents sent into a brain structure to activate
it
• Transcranial magnetic stimulation (TMS)
– New technique that temporarily enhance or depress activity in
a specific area of the brain
(about 2 centimeters in to the brain)
 CT (computed tomography) Scan
 a series of x-ray
photographs taken from
different angles and
combined by computer into
a composite representation
of a slice through the body;
also called CAT scan
 Two-dimensional
Sample image: Perfusion CT in a patient with
stroke demonstrates the part of the brain with
severely decreased blood flow (arrows).
What are some common uses of the procedure?
• Detection of bleeding, brain damage and skull fractures in
patients with head injuries.
• Detects a blood clot or bleeding within the brain shortly after a
patient exhibits symptoms of a stroke.
• Detection of most brain tumors.
• Planning radiation therapy for cancer of the brain or other tissues.
• Guiding the passage of a needle used to obtain a tissue sample
(biopsy) from the brain.
PET Scan
PET (positron emission tomography) Scan
 a visual display of brain activity (metabolic activity) that detects where a radioactive
form of glucose goes while the brain performs a given task
PET Scan Process
• observe blood flow or metabolism in
any part of the brain.
• subject is injected with small quantity
of radioactive glucose
• Brain cells use glucose as fuel
• shows levels of activity as a color-coded
brain map
• red indicates more active brain areas,
• Blue/green: less active areas.
• gray outer surface is MRI picture of the
surface of the brain inner colored
structure is cingulate gyrus, part of the
brain's emotional system
MRI Scan
MRI (magnetic resonance imaging)
 technique uses magnetic fields and radio waves
 produces computer-generated images
 distinguish among different types of soft tissue
 allows us to see structures within the brain
 A brief pulse of radio waves
disorients the brain’s atoms
momentarily, when the
atoms return to their
normal spin, they release
detectable signals.
Healthy brain (left)
schizophrenic brain (right)
enlarged fluid filled
brain region
Examples of PET and MRI techniques
Thalamus
Cortex
•These 2 images show subjects who received a painful injection of the chemical capsaicin
into the upper arm. show increased blood flow (the PET scan shows the thalamus and
primary somatosensory cortex after the injection. The gray areas of the images (the MRI)
Using this method can identify the areas of the brain that are active during specific
conditions.
•could be used to study just about any other cognitive function.
fMRI Scan
• Functional magnetic resonance imaging (fMRI)
– New MRI that monitors blood flow and oxygen consumption
in the brain to identify areas of high activity
– Higher resolution than a PET scan
– Probing the Anatomy of Sexual Arousal
• p. 96 Discussion
Brain Structures
• The brain has three main parts:
the forebrain, midbrain, and
hindbrain.
• The forebrain: cerebrum,
thalamus, hypothalamus, &
Limbic system
• The midbrain: part of the
brainstem
• The hindbrain: cerebellum, pons
and medulla (lower part of the
brainstem)
Lower-Level Brain Structures
 Brainstem




the oldest part
central core of the brain
beginning where the spinal cord swells as it enters the skull
responsible for automatic survival functions
 Medulla [muh-DUL-uh]
 base of the brainstem
 controls heartbeat and breathing
The Brain
Brain stem
• "brain stem" is the part of your
brain that was first to evolve in
primitive human beings.
• called a "reptilian brain" since it
resembles almost the whole brain
of a reptile.
• source of all your instincts and
feelings!
• links your brain to your "spinal
cord.“
• It is where all the incoming and
outgoing "messages" come
together and cross over.
Controls sleeping,
waking, and dreaming
 Reticular Formation (the panty hose)
 a nerve network inside the brainstem that plays an important
role in controlling arousal/sleep
 Severe damage can induce a coma
 Located in the brainstem
 Thalamus [THAL-uh-muss] (411 operator)
 the brain’s sensory switchboard, located on top of the
brainstem; communication passes through
 it directs messages to the sensory receiving areas in the cortex
and transmits replies to the cerebellum and medulla
Cerebellum [sehr-uh-BELL-um]
“Sarah the Southern Belle”
 the “little brain” attached
to the
rear of the brainstem
 it helps coordinate
voluntary movement and
balance
 Important in walking,
balance, or shaking hands
The Limbic System
 Limbic System: a doughnut-shaped system of neural structures
at the border of the brainstem and cerebral hemispheres
 emotions such as fear and aggression
 basic drives such food and sex
 includes the hippocampus, amygdala, and hypothalamus.
 Amygdala [ah-MIG-dah-la]
 two almond-shaped neural clusters that are components of the
limbic system and are linked to emotion (aggression/rage and
fear)
Hypothalamus:
 neural structure lying below (hypo) the
thalamus; directs several maintenance
activities
 eating
 drinking
 body temperature
 helps govern the endocrine system via
the pituitary gland
 is linked to emotion
 “pleasure center” or “reward center”
The Limbic System
 Electrode
implanted in
reward center
 So reinforcing that
the mouse pressed
the pedal up to
7000x in one hour
The Cerebral Cortex
Cerebral Cortex
 the intricate fabric of interconnected neural cells that
covers the cerebral hemispheres
 the body’s ultimate control and information processing
center
Glial Cells- glue cells
 cells in the nervous system that support, nourish, and
protect neurons
Cerebral Cortex: Basic Subdivisions
Structure of the Cerebral Cortex
Frontal Lobes “behind your forehead”
 involved in speaking and muscle movements and in making
plans (initiative) and judgments (morality)
Parietal Lobes “top and rear”
 include the sensory cortex
Occipital Lobes “back of head”
 include the visual areas, which receive visual information from
the opposite visual field
Temporal Lobes “above the ears”
 include the auditory areas
Function of the Cerebral Cortex
Motor Cortex
 area at the rear of the frontal lobes that controls voluntary
movements
Sensory Cortex
 area at the front of the parietal lobes that registers and
processes body sensations
The Cerebral Cortex
The Cerebral Cortex
 Functional MRI scan
shows the visual cortex
(occipital lobes)
activated as the subject
looks at faces
Visual and Auditory Cortex
Occipital Lobes
Temporal Lobes
Association Areas
 More intelligent animals have increased “uncommitted” or
association areas of the cortex
The Cerebral Cortex & Language
Aphasia
 impairment of language, usually caused by left hemisphere
damage either to Broca’s area (impairing speaking) or to
Wernicke’s area (impairing understanding)
Broca’s Area
 an area of the left frontal lobe that directs the muscle
movements involved in speech
Wernicke’s Area
 an area of the left temporal lobe involved in language
comprehension and expression
Specialization and Integration
Specialization and Integration
 Brain activity when hearing, seeing, and speaking words
The Cerebral Cortex:
Brain Reorganization
 Plasticity
 the brain’s capacity for modification, as evident in brain
reorganization following damage (especially in children) and in
experiments on the effects of experience on brain development
 Children have a surplus of neurons
 When one area is damaged, other areas may in time reorganize and take
over some of its functions
 “stem cell research”
Our Divided BrainS
Corpus callosum
Corpus Callosum
 large band of neural
fibers
 connects the two
brain hemispheres
 carries messages
between the
hemispheres
 Transfer more than a
billion bits of info per
sec.
Our Divided Brains
 The information
highway from the eye to
the brain
 The opposite side of the
brain’s hemisphere
controls the opposite
side of the body
Hemispheric Specialization
The Hemispheres of the Brain
Clinical neurologists Gereon Fink of the University of
Düsseldorf in Germany and John Marshall from the
Radcliffe Infirmary in Oxford, pursued the idea that the
difference between the two hemispheres lay in their style
of working.
“The left brain does the work that no
one in their right mind would want
to do.”
-Amanda Barrow
1st period
The Left Hemisphere
(Verbal)
• The left brain focuses on detail.
• It is the natural home for all mental skills that need us to act in a
series of discrete steps or fix on a particular fragment of what we
perceive.
• skills such as recognizing a friend's face in a crowd or "lining up"
words to make a sentence.
LEFT Hemisphere FUNCTIONS
Speech
Language
Logic
Writing
RIGHT
Hemisphere
FUNCTIONS
•concentrates on the broad,
background picture.
•It has a panoramic focus..
•good at seeing general connections
•best able to represent the relative position of objects in space
•handles emotional and metaphorical aspects of speech.
Right Hemisphere Functions
Spatial Reasoning
Art
Music
Emotions
• So, in a neat and complementary division of labor, one
side of the brain thinks and sees in wide-angle while the
other zooms in on the detail.
• To examine the functions carried out by
each hemisphere, neurologists scanned
the brain of subjects while they were
shown a series of letter navons. A letter
navon is a large letter composed of
smaller letters as shown in the side box.
The researchers soon found out that while
the subjects concentrated on the small
F's, the left hemisphere showed greater
activity; when they focused on the big S,
the right hemisphere became active.
• Thus, they had demonstrated that the left
hemisphere focused on the details, while
the right perceived the overall,
background picture.
Split Brain
 A condition in which the two
hemispheres of the brain are
isolated by cutting the
connecting fibers (corpus
callosum) between them.
Split Brain
Sperry & Gazzaniga
“What word
did you see?”
or
“Look at the dot.”
Two words separated
by a dot are
momentarily projected.
“Point with
your left
hand to the
word you
saw.”
Split Brain
• Only 10 split-brain studies
• Perceptual asymmetries- right and left imbalances btwn the
cerebral hemispheres in the speed of visual or auditory processing
-This corresponds with split-brain studies and shows the specialization of
the hemispheres
Test yourself for Split Brain
• Perform the following task simultaneously. You should
be able to do both tasks with ease if you are split-brain
• Draw a picture of a house; include windows, door,
chimney with either hand
• With the other hand, write your first and last name in
cursive writing.
• You can’t stop one task to work the other!
Neural and Hormonal Systems
Neural Communication
Biological Psychology
 branch of psychology concerned with the links between
biology and behavior
 some biological psychologists call themselves behavioral
neuroscientists, neuropsychologists,
 behavior geneticists, physiological psychologists, or
biopsychologists
Neural Communication
Neuron
 a nerve cell
 the basic building block of the nervous system
cell body contains the nucleus, mitochondria and other organelles typical of
eukaryotic cells.
Dendrite
 the bushy, branching extensions of a neuron that receive messages and
conduct impulses toward the cell body
Axon
 the extension of a neuron, ending in branching terminal fibers, through
which messages are sent to other neurons or to muscles or glands, sends
info away from cell body
Neural Communication
 Myelin [MY-uh-lin] Sheath
 a layer of fatty cells
segmentally encasing the
fibers of many neurons
 enables vastly greater
transmission speed of
neutral impulses
Neural Communication
Neural Communication
Action Potential
 a neural impulse; a brief electrical charge that travels down an
axon
 generated by depolarization (the movement of positively
charged atoms in and out of channels in the axon’s membrane)
Threshold
 the level of stimulation required to trigger a neural impulse
Neural Communication
Synapse [SIN-aps]
 junction between the axon tip of the sending neuron and the
dendrite or cell body of the receiving neuron
 tiny gap at this junction is called the synaptic gap or cleft
Neurotransmitters
 chemical messengers that travel the synaptic gaps between
neurons
 when released by the sending neuron, neurotransmitters travel
across the synapse and bind to receptor sites on the receiving
neuron, thereby influencing whether it will generate a neural
impulse
Neural Communication
Cell body end
of axon
Direction of neural impulse: toward axon terminals
Neural Communication
FILM
Chapter 2: Embryonic and Fetal Brain Development (13 min 28 sec) Safari
Montage
http://videoservicesondemand.volusia.k12.fl.us/SAFARI/montage/schoolnews.html
FLUSHING TOILET
• All or None Principle: once the
handle is pushed and the toilet
begins flushing, there is no
stopping it.
• Once a neuron is fired, it cannot
be stopped or it’s message taken
back
• Like a gun, either a neuron fires or
it doesn’t.
• The strength of the stimulus does
not affect the action potential
speed.
Direction of Impulse
• A toilet only flows one wayout into the sewage system.
The direction never changes.
A toilet that is working
properly never flows up.
• A neuron always fires the
impulse in a specific
direction- towards the target
Refractory Period
• Brief period of time after you flush
the toilet during which the handle
is useless and the toilet cannot be
flushed again.
• Same for a neuron, which limits
the number of times a neuron can
be fired per second.
• When positively charged ions are
pumped back outside the neural
membrane
• A camera flash that pauses to
recharge
THRESHOLD:
• There is a specific level of intensity
and a limit to the volume that it is
possible to flush down a toilet
• The amount of pressure required
to push the trigger to flush the
toilet
• When a toilet is being flushed, a
minimum intensity of water
pressure is needed in order for the
toilet to function properly.
• The level of stimulation required
to trigger a neural impulse.
Resting Potential
• When the toilet is not being
flushed, no water moves in or out
and is stable. Ready to be flushed
immediately
• When a neuron is at rest it too is
stable;
• It is at a polarized state
• A resting axon has an excess of
neg. charged ions inside and the
fluid outside of an axon membrane
has an excess of pos. charged ions.
Action Potential
• A neural impulse
• When a neuron is at a
depolarized state
• Brief electrical charge that
travels down an axon
• When a neuron’s receptor is
stimulated, ions rush in and
energy flows down the axon
• The toilet handle is pushed to
initiate water rushing into
and flowing down the toilet
Depolarization
• Pushing the handle stimulates
the toilet into action. New
water coming into the bowl. the
flow of positively charged ions
into the axon leads the axon to
become positively charged
relative to the outside.
• Causes the next channel to
open.
• Domino effect
Depolarization
Neural Communication
Neural Communication
Serotonin Pathways
Dopamine Pathways
Neural Communication
Acetylcholine [ah-seat-el-KO-leen]
 a neurotransmitter that, among its functions, triggers muscle
contraction…& thus, movement
 Linked to Alzheimer's disease
Endorphins [en-DOR-fins]
 “morphine within”
 natural, opiate-like neurotransmitters
 linked to pain control and to pleasure
Neural Communication
Neurotransmitter
molecule
Receptor site on
receiving neuron
Receiving cell
membrane
Agonist mimics
neurotransmitter
Antagonist
blocks
neurotransmitter
Agonist –vs- Antagonist
•
•
•
•
Excitatory
Can mimic the nt
Can block nt’s reuptake
Opiates enhance normal
arousal or sensation of
pleasure
• Ecstacy enhances sexual
arousal
• Inhibitory
• Prevents the nt’s release
• Or occupy its receptor site
and block its effect
• Is similar but not enough to
stimulate the receptor
• Foreign money in a snack
machine
Ecstasy commonly appears in a tablet form, usually imprinted with a monogram
Neurotransmitter Agonist.
Film: Club Drugs
• MDMA (3,4-methylenedioxymethamphetamine), most
commonly known by the street names ecstasy or XTC primary
effect is believed to be the stimulation of secretion as well as
inhibition of re-uptake of large amounts of serotonin as well as
dopamine and norepinephrine in the brain, inducing a general
sense of openness, empathy, energy, euphoria, and well-being.
Tactile sensations are enhanced for some users, making general
physical contact with others more pleasurable;
• Good medical use has been the reported ability to facilitate selfexamination with reduced fear may prove useful in some
therapeutic settings, 2001: permission granted to FDA for testing
in patients with post-traumatic stress disorder .
BOTOX
Antagonist
• botox is toxic compound. It is an enzyme that breaks down one of the fusion
proteins that allow neurons to release acetylcholine. Small doses block the
release of acetylcholine by nerve cells that signal muscle contraction.
• Botox originally produced for the intended relief of uncontrollable muscle
spasms. First approved in 1989 to treat two eye muscle disorders-uncontrollable blinking (blepharospasm) and misaligned eyes (strabismus
• Increasingly being used for cosmetic purposes, to paralyse facial muscles as a
means of concealing wrinkles.
NICOTINE
Agonist
• an increase in acetylcholine causes a increased heart rate and
increased production of saliva.
• Nicotine acts by increasing the activity of certain acetylcholine
receptors Nicotine is a potent nerve poison and is included in
many insecticides.
• In lower concentrations, is a stimulant and one of the main factors
leading to the pleasure and habit-forming qualities of tobacco
smoking.
NEUROTRANSMITTER ANTAGONIST
• Curare is a potent neurotoxin. Used as an arrow poison by some
Indian peoples of South America
• Death from curare is caused by loss of the ability to breathe as a
result of paralysis. The alkaloid curare molecule mimics the
neurotransmitter acetylcholine by binding to its receptor at
muscle synapses. This prevents nerves from stimulating muscle
contraction.
NEUROTRANSMITTER
Agonist
• The venom of a black widow
spider causes a synaptic flood
of ACH.
• Results in violent muscle
contractions, convulsions,
and possible death.
Bipolar Disorders
• occurs with equal frequency in men and women. The
peak age of onset is during late teens.
• Neurotransmitter abnormalities in a number of
pathways including serotonin, norepinephrine,
dopamine, acetylcholine
• thalamus, hypothalamus, amygdala, prefrontal cortex,
and cerebellum.
The Nervous System
Nervous System
 the body’s speedy, electrochemical communication system
 consists of all the nerve cells of the peripheral and central
nervous systems
Central Nervous System (CNS)
 the brain and spinal cord
Peripheral Nervous System (PNS)
 the sensory and motor neurons that connect the central
nervous system (CNS) to the rest of the body
The Nervous System
Nervous
system
Central
(brain and
spinal cord)
Peripheral
Autonomic (controls
self-regulated action of
internal organs and glands)
Somatic
Skeletal (controls
voluntary movements of
skeletal muscles)
Sympathetic
(arousing)
Parasympathetic
(calming)
The Nervous System
Nerves
 neural “cables” containing many axons
 part of the peripheral nervous system
 connect the central nervous system with muscles, glands, and
sense organs
Sensory Neurons
 neurons that carry incoming information from the sense
receptors to the central nervous system
The Nervous System
Interneurons
 CNS neurons that internally communicate and intervene
between the sensory inputs and motor outputs
Motor Neurons
 Longest portion is the axon
 carry outgoing information from the CNS to muscles and glands
Peripheral Nervous System
1. Somatic Nervous System – voluntary (skeletal)
2. Autonomic nervous system- involuntary (glands/muscles)
Peripheral Nervous System
Somatic Nervous System
 the division of the peripheral nervous system that controls the
body’s skeletal muscles
 Afferent neurons- carry information inward to the central nervous
system from the periphery of the body
 Efferent neurons- carry information outward from the central
nervous system to the periphery of the body
The Nervous System
Autonomic Nervous System
 the part of the peripheral nervous system that controls the
glands and the muscles of the internal organs (such as the
heart)
A. Sympathetic Nervous System
 division of the autonomic nervous system that arouses the
body, mobilizing its energy in stressful situations
 Fight or Flight
B. Parasympathetic Nervous System
 division of the autonomic nervous system that calms the body,
conserving its energy
The Autonomic Nervous System
chart on p. 91
The Autonomic Nervous System
chart on p. 91
The Nervous System
Reflex
 a simple, automatic, inborn response to a sensory stimulus
Brain
Sensory neuron
(incoming information)
Muscle
Skin
receptors
Motor neuron
(outgoing
information)
Interneuron
Spinal cord
The Nervous System
Neurons in the brain
connect with one
another to form networks
Inputs
The brain learns by modifying
certain connections in
response to feedback
Neural Networks
 interconnected neural
cells
 with experience, networks
can learn, as feedback
strengthens or inhibits
Outputs
connections that produce
certain results
The Endocrine System
Endocrine System
 the body’s “slow”
chemical communication
system
 a set of glands that
secrete hormones into
the bloodstream
Neural and Hormonal Systems
Hormones
 chemical messengers, mostly those manufactured by the endocrine glands,
that are produced in one tissue and affect another
Adrenal [ah-DREEN-el] Glands
 a pair of endocrine glands just above the kidneys
 secrete the hormones epinephrine (adrenaline) and norepinephrine
(noradrenaline), which help to arouse the body in times of stress
Pituitary Gland
 under the influence of the hypothalamus, the pituitary regulates growth and
controls other endocrine glands
• The adrenal glands are orange-colored endocrine glands
which are located on the top of both kidneys
Pituitary Gland
The Master Gland
• Prolactin - Prolactin stimulates milk production from the breasts after childbirth
• Growth hormone or GH - GH stimulates growth in childhood
• In adults it is important for maintaining muscle mass as well as bone mass. It also affects fat
distribution in the body.
• Adrenocorticotropin or ACTH - ACTH stimulates production of cortisol by the adrenal glands.
Cortisol, a so-called "stress hormone" is vital to survival
• Luteinizing hormone or LH - LH regulates testosterone in men and estrogen in women.
• Follicle-stimulating hormone or FSH - FSH promotes sperm production in men and stimulates
the ovaries to enable ovulation in women
• Thyroid-stimulating hormone or TSH - TSH stimulates the thyroid gland, which regulates the
body's metabolism, energy, growth and development
• Follicle-stimulating hormone or FSH - FSH promotes sperm production in men and stimulates
the ovaries to enable ovulation in women
•
•
"Gene Therapy": production of transgenic mice
Mice homozygous for a dwarfism gene (lit / lit) grow at a slow rate. An artificial plasmid (top
left) is constructed that combines a rat growth-hormone (RGH) gene fused to a mouse
metallothionein promoter (MP) gene. A large number of these plasmids are then injected into
fertilized eggs of mice; in a small fraction of cases the plasmid is stabily integrated into the
mouse's chromosomes. Production of RGH can then be induced by exposure of the embryo to
heavy-metals, which activates the MP promoter. The resulting transgenic offspring (left) weighs
44g (its control sibling weighs 29g). The recombinant chromosome is subsequently inherited in
a Mendelian dominant pattern.
Gigantism
• Gigantism is an excessive secretion of
growth hormone during childhood
before the closure of the bone growth
plates, which causes overgrowth of the
long bones and very tall stature. he
vertical growth in height that marks this
condition is also accompanied by
growth in muscles and organs, which
makes the child extremely large for his
or her age. The disorder can also delay
puberty.
The Doughnut Assignment
• Select a doughnut that best represents your limbic
system
• Place skittles in the sequential order for the following:
• Hypothalamus: green skittle
• Pituitary gland: yellow skittle
• Amygdala: 2 peanut M&Ms
• Hippocampus: orange skittle
• “Bon Appetite”
Practice Test
1. A neural impulse is initiated when a neuron’s charge
momentarily becomes less negative, or even positive. This event
is called:
a.
b.
c.
d.
An action potential
A resting potential
Impulse facilitation
Inhibitory
Practice Test
2. Neurons convey information about the strength of stimuli by
varying:
a.
b.
c.
d.
The size of their action potentials
The velocity of their action potentials
The rate at which they fire action potentials
All of the above
Practice Test
3. Alterations in activity at dopamine synapse have been implicated
in the development of:
a.
b.
c.
d.
Anxiety
Schizophrenia
Alzheimer's disease
Nicotine addiction
Practice Test
4. Tania just barely avoided a head-on collision on a narrow road. With heart
pounding, hands shaking, and body perspiring. Tania recognizes that these
are signs of the body’s fight or flight response, which is controlled by the:
a.
b.
c.
d.
Empatheic division of the peripheral nervous system
Parasympathetic division of the autonomic nervous system
Somatic division of the peripheral nervous system
Sympathetic division of the autonomic, nervous system
Practice Test
5. The hindbrain consists of the:
a.
b.
c.
d.
Endocrine system and the limbic system
Reticular formation
Thalamus, hypothalamus, and cerebrum
cerebellum, medulla, and pons
Practice Test
6. Juan is watching a basketball game. The neural impulses from his
eyes will ultimately travel to his primary visual cortex, but first
they must pass through the:
a.
b.
c.
d.
Amygdala
Hypthalamus
Thalamus
pons
Practice Test
7. The ______ lobe is to hearing as the occipital lobe is to vision.
a.
b.
c.
d.
Frontal
Temporal
Parietal
cerebellar
Practice Test
8. Paul has profound difficulty producing spoken language. If his
problem is attributable to brain damage, the damage would
probably be found in:
a.
b.
c.
d.
The cerebellum
Sperry’s areas
Broca’s area
Wernicke’s area
Practice Test
9. Sounds presented to the right ear are registered:
a.
b.
c.
d.
Only in the right hemisphere
Only in the left hemisphere
More quickly in the right hemisphere
More quickly in the left hemisphere
Practice Test
10. In people whose corpus callosums have not been severed, verbal
stimuli are identified more quickly and more accurately:
a.
b.
c.
d.
When sent to the right hemisphere first
When sent to the left hemisphere first
When presented to the left visual field
When presented auditorally rather than visually
Practice Test
11. Hormones are to the endocrine system as _________ are
to the nervous system.
a.
b.
c.
d.
Nerves
Synapses
Neurotransmitters
Action potentials
Homework Review
1. Which of the following parts of the brain is most active in
decision-making?
(a) Reticular formation
(b) Corpus Callosum
(c) Hypothalamus
(d) Cerebral cortex
(e) Pituitary gland
2. An individual experiencing a low blood- glucose level would
be best advised to do which of the following?
(a) take a nap
(b) eat a snack
(c) drink a glass of water
(d) drink a diet soda
(e) get some exercise
3.One suspected cause of schizophrenia is the abnormal increase
of which of the following neurotransmitters in the brain?
(a) Acetylcholine
(b) Somatotropin
(c) Dopamine
(d) Norepinephrine
(e) serotonin
4.For most people, speech functions are primarily localized in the
(a) right Cerebral hemisphere
(b) left cerebral hemisphere
(c) Occipital lobe
(d) Corpus Callosum
(e) Cerebellum
5. People who have experienced severe damage to the frontal
lobe of the brain seldom regain their ability to
(a) make and carry out plans
(b) recognize visual patterns
(c) process auditory information
(d) process olfactory information
(e) integrate their multiple personalities
6. Which of the following is a brain-imaging technique that
produces the most detailed picture of brain structure?
• (a) Electroencephalography (EEG)
• (b) Magnetic Resonance Imaging (MRI)
• (c) Positron Emission Tomography (PET)
• (d) Computerized Axial Tomography (CAT)
• (e) Electromyography (EMG)
7. Stimulations of portions of the left temporal lobe of the brain
during surgery will cause the patient to
(a) see lights
(b) lose the sense of smell
(c) jerk the left arm
(d) extend the tongue
(e) hear sounds
8. The role of the parasympathetic division of autonomic nervous
system is to
(a) facilitate the body’s fight-or-flight response
(b) prepare the body to cope with stress
(c) promote rapid cognitive processing
(d) prompt the body to use its resources in responding to
environmental stimuli
(e) establish homeostasis after a fight-or-flight response
9. Which of the following occurs when a neuron is stimulated to its
threshold?
(a) the movement of sodium and potassium ions across the
membrane creates an action potential
(b) the neuron hyperpolarizes.
(c) neurotransmitters are released from the dendrites
(d) the absolute refractory period of the neuron prevents it from
responding.
(e) the neuron’s equilibrium potential is reached
10. The thalamus processes information for all of the following
senses EXCEPT
(a) smell
(b) hearing
(c) taste
(d) vision
(e) touch