Download Unit III Modules 9 to 13 Test Review

Unit III, Modules 9-13 Test
Review
• See also the Unit III notes and pages 76-122
• About 45 m.c., plus two essays; one on brain
functioning, the other review concepts from
previous units.
• Some practice questions are embedded in this
presentation
• Other practice questions are available at the
textbook website and in the textbook after each
module.
Neuron
Order of a transmission: dendrite, cell body,
axon, synapse (see arrow below)
Neural Communication
Neurons, 80
Neural Communication
• (a)Dendrite
– the bushy, branching extensions of a neuron that receive
messages and conduct impulses toward the (b)cell body
• (c)Axon
– the extension of a neuron, ending in branching terminal
fibers, through which messages are sent to other neurons or
to muscles or glands
• Myelin [MY-uh-lin] Sheath
– a layer of fatty cells segmentally encasing the fibers of
many neurons
– makes possible vastly greater transmission speed of neutral
impulses,
– Damage to can lead to Multiple sclerosis
Neural Communication
• Action Potential
– a neural impulse; a brief electrical charge that
travels down an axon; DEPOLARIZED
– generated by the movement of positively charges
atoms in and out of channels in the axon’s
membrane
• Threshold
– the level of stimulation required to trigger a neural
impulse
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.
Practice question
• Multiple sclerosis is a disease that is most
directly associated with the degeneration of:
a. the myelin sheath.
b. the pituitary gland.
c. endorphins.
d. dendrites.
Myelin Sheath
– a layer of fatty cells segmentally encasing the fibers
of many neurons
– makes possible vastly greater transmission speed of
neutral impulses,
– Damage to can lead to Multiple sclerosis
Sensory neurons
• 1. Shoulder receptors detected the squeeze
• Sensory neurons carried the info to your spinal
cord
• Sensory Neurons carry incoming information
from the sense receptors to the CNS.
Sensory Neuron
(Bipolar)
Interneurons
• carried the information to your brain
• Interneurons in your brain interpreted the
info: “Hey someone squeezed my
shoulder!”
• Interneurons connect the other two
neurons
Interneuron Neuron (Unipolar)
Motor neurons
• carried the command for your hand to
squeeze the shoulder of the person in front
of you.
• Motor Neurons carry outgoing
information from the CNS to muscles
and glands.
Motor Neuron
(Multipolar)
Kinds of neurons and their location
• Interneurons
– Central Nervous System (CNS) neurons that internally
communicate and intervene between the sensory inputs and
motor outputs
• Motor Neurons in the peripheral nervous system
– carry outgoing information from the CNS to muscles and
glands
– Skeletal Nervous System
– the division of the peripheral nervous system that controls
the body’s skeletal muscles
Kinds of Neurons, 62
Sensory Neurons carry incoming information from the
sense receptors to the CNS. Motor Neurons carry
outgoing information from the CNS to muscles and
glands. Interneurons connect the two neurons.
Interneuron Neuron
(Unipolar)
Sensory Neuron
(Bipolar)
Motor Neuron
(Multipolar)
Refractory Period & Pumps, 56
Refractory Period: After a neuron fires an action
potential it pauses for a short period to recharge
itself to fire again.
Sodium-Potassium Pumps: Sodium-potassium
pumps pump positive ions out from the inside
of the neuron, making them ready for another
action potential.
Threshold, 56
Threshold: Each neuron receives depolarizing
and hyperpolarizing currents from many
neurons. When the depolarizing current
(positive ions) minus the hyperpolarizing
current (negative ions) exceed minimum
intensity (threshold) the neuron fires an action
potential.
Action Potential, 55
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.
Action Potential Properties
All-or-None Response: When the depolarizing
current exceeds the threshold, a neuron will
fire. If the depolarizing current fails to exceed
the threshold, a neuron will not fire.
Intensity of an action potential remains the
same throughout the length of the axon.
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.
Neurotransmitters: chemical
messengers released into synapse
Reuptake: Prozac effects
prevention of for serotonin
Neurotransmitters in the
synapse are reabsorbed
into the sending neurons
through the process of
reuptake.
This process applies the
brakes on
neurotransmitter action.
Antidepressant drugs and serotonin,
Antidepressant drugs like
Prozac, Zoloft, and Paxil
are Selective Serotonin
Reuptake Inhibitors
(SSRIs) that improve the
mood by elevating levels
of serotonin by
inhibiting reuptake
Can lead to
neurogenesis: new
brain cells.
Agonists (see 82)
Botox as an antagonist, 83
A poison (botulin) is injected into the face to
block the working of ACh and relaxing the
facial muscles. Re-injections are needed.
http://test.selfinnovations.com/sc/images/crowsBefore.gif
Curare: an antagonist
• Curare acts only at muscular synapses and NOT at
the synapses of the central nervous system (curare
does not cross the blood-brain barrier),
• Thus, a victim of curare poisoning may be aware
of what is happening until the very end.
• The victim can feel the paralysis progressing but is
quickly unable to move, call out or gesture.
• If artificial respiration is performed throughout,
the victim usually recovers without ill effects.
How it affects the body
• Death from curare is caused by paralysis of the
respiratory muscles.
• The alkaloid curare molecule mimics the
neurotransmitter ACETYLCHOLINE by binding
to its receptor at muscle synapses. ACTS AS AN
ANTAGONIST.
• This prevents nerves from stimulating muscle
contraction.
• Paralysis sets in gradually, because curare must
compete for receptor binding sites before
occupying them
Practice question
• Botox injections smooth facial wrinkles
because botulin is a(n):
a. ACh antagonist.
b. dopamine antagonist.
c. ACh agonist.
d. dopamine agonist.
Agonists and antagonists, 59
• These are NOT neurotransmitters
• Agonists mimic (act like) the action of
neurotransmitters
• Example: nicotine mimics Ach
• Antagonists block the action of
neurotransmitters
• Example: curare blocks Ach (leading to
paralysis of muscles)
Practice question
• A drug that blocks the reuptake of a
particular neurotransmitter is called a(n):
a. opiate.
b. antagonist.
c. glutamate.
d. agonist.
Motor neurons (CNS)
• carried the command for your hand to
squeeze the shoulder of the person in front
of you.
• Motor Neurons carry outgoing
information from the CNS (brain and
spinal column) to muscles and glands.
Motor Neuron
(Multipolar)
An Examination of the effect of
autonomic nervous system on
heart rate
• One set of nerves, the sympathetic nervous
system (SNS), is the fight or flight system,
mobilizing your body.
• Another set of nerves, the parasympathetic
nervous system (PNS) works to slow down
the body’s resources
Parasympathetic
Sympathetic
• Like a symphony:
gets you excited
Practice question
• The peripheral nervous system consists of:
a. association areas.
b. the spinal cord.
c. the reticular formation.
d. sensory and motor neurons.
Interneurons
• carried the information to your brain
• Interneurons in your brain interpreted the
info: “Hey someone squeezed my
shoulder!”
• Interneurons connect the other two
neurons
Interneuron Neuron (Unipolar)
Reflex
• a simple, automatic, inborn response to a
stimulus
Brain
Sensory neuron
(incoming information)
Muscle
Skin
receptors
Motor neuron
(outgoing
information)
sensory
Interneuron
Spinal cord
Hormonal System
• Endocrine System
– the body’s “slow”
chemical
communication
system
– a set of glands that
secrete hormones
into the bloodstream
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, 91
Adrenal glands consist of the adrenal medulla and
the cortex. The medulla secretes hormones
(epinephrine and norepinephrine) during stressful
and emotional situations, while the adrenal cortex
regulates salt and carbohydrate metabolism.
Electroencephalogram (EEG), 95
AJ Photo/ Photo Researchers, Inc.
– 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
PET Scan, 68
Courtesy of National Brookhaven National Laboratories
PET (positron
emission
tomography) Scan is
a visual display of
brain activity that
detects a radioactive
form of glucose
while the brain
performs a given
task.
MRI Scan, 68
MRI (magnetic resonance
imaging) uses magnetic
fields and radio waves to
produce computer-generated
images that distinguish
among different types of
brain tissue.
Both photos from Daniel Weinberger, M.D., CBDB, NIMH
Practice question
• Which of the following would be most
useful for detecting the brain areas that are
most active as a person performs
mathematical calculations?
a. a brain lesion
b. an fMRI
c. a PET scan
d. a hemispherectomy
Corpus
callosum
Cerebral cortex
Right hemisphere
Left hemisphere
Thalamus
Hypothalamus
Pituitary
Amygdala
Reticular
formation
Medulla
Hippocampus
Spinal
cord
Cerebellum
Cerebral cortex
Limbic system
Brainstem
Brain Stem, 71
The Medulla is the
base of the brainstem
that controls heartbeat
and breathing.
Reticular Formation is
a nerve network in the
brainstem that plays
an important role in
controlling arousal
and alertness.
The thalamus (Hal + Amos) 72
The brain’s sensory
switchboard, located on
top of the brainstem.
It directs messages to the
sensory areas (visual,
auditory, all except smell)
in the cortex and transmits
replies to the cerebellum
and medulla.
Reward Center: Hypothalamus
Sanjiv Talwar, SUNY Downstate
Rats cross an electrified
grid for self-stimulation
when electrodes are
placed in the reward
(hypothalamus) center
(top picture). When the
limbic system is
manipulated, a rat will
navigate fields or climb
up a tree (bottom
picture).
Hypothalamus (Hypo the Llamas)
– neural structure lying below (hypo) the thalamus
– directs several maintenance activities
• eating
• drinking
• body temperature
– helps govern the endocrine system via the pituitary
gland
The Limbic System: Regulation of
emotion primarily occurs in this area
Practice question
• The limbic system structure that regulates
hunger is called the:
a. thalamus.
b. amygdala.
c. hippocampus.
d. hypothalamus.
Association Areas, 79
• areas of the
cerebral cortex that
are not involved in
primary motor or
sensory functions
• involved in higher
mental functions
such as learning,
remembering,
thinking, and
speaking or
recognizing faces
Cerebral Cortex Lobes
• Frontal Lobes
– involved in speaking and muscle movements and in making
plans and judgments
• Parietal Lobes
– include the sensory cortex
• Occipital Lobes
– include the visual areas, which receive visual information
from the opposite visual field
• Temporal Lobes
– include the auditory areas (hearing)
Parietal lobe, 76
• Awareness of
where your feet
and hands are
(proprioception)
Frontal lobe, 76
• Deciding your
driving destination
and how you will get
there
• Conscious control of
voluntary movement
Temporal lobe, 76
• Interpreting
auditory
information about
traffic
• Balance
(vestibular sense)
Occipital lobe, 76
• Interpreting visual
information from
the instrument
panel and traffic
Practice question
• The regions of the parietal lobes that are
involved in mathematical and spatial
reasoning are known as:
a. the angular gyrus.
b. Wernicke's areas.
c. the reticular formation.
d. association areas.
Practice question
• Brain scans indicate that well-practiced
pianists have a larger-than-usual auditory
cortex area that encodes piano sounds. This
best illustrates:
a. hemispherectomy.
b. tomography.
c. aphasia.
d. plasticity.
Cerebellum 98
The “little brain”
attached to the rear of
the brainstem. It helps
coordinate voluntary
movements and
balance.
Amygdala 99
The Amygdala consists of
two almond-shaped neural
clusters linked to the
emotions of fear and anger.
Hippocampus
• Contributes to the
formation of memories
The cerebellum
• Cerebellum [sehr-uhBELL-um]
– the “little brain”
attached to the rear of
the brainstem
– it helps coordinate
voluntary movement
and balance
Motor and sensory 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, most critically touch
– See next slide for location and specifics
The Sensory and Motor Cortex
Phineas Gage, see page 110
• Suffered frontal lobe
damage.
• His personality changed
from friendly to
combative.
• More recently scientists
have argued that these
differences were
exaggerated. He largely
adjusted to this brain
trauma.
Practice question
• Following massive damage to his frontal
lobes, Phineas Gage was most strikingly
debilitated by:
a. aphasia.
b. memory loss.
c. auditory hallucinations.
d. irritability.
Brain Plasticity, 110-2
• The idea that the
brain, when
damaged, will
attempt to find
news ways to
reroute
messages.
• Children’s brains
are more plastic
than adults.
Neurogenesis
= the formation of new neurons.
Splitting the Brain
A procedure in which the two hemispheres of the brain
are isolated by cutting the connecting fibers (mainly
those of the corpus callosum) between them; used by
neurosurgeons to reduce epileptic seizures.
Courtesy of Terence Williams, University of Iowa
Consciousness, 118
= our awareness of ourselves and our
environment.
Dual Processing, 120
= processing the principle that information
is often simultaneously processed on
separate conscious and unconscious
tracks.
Essays
• #1 The topic is “Super Heroes”
• #2 A review of some key terms from Chapter 18
and some material from Ch. 2