Sensory Pathways and the Somatic Nervous System- Ch 15

Question 1

The primary sensory cortex of the cerebral hemispheres or areas of the cerebellar hemispheres receives __________.

somatic motor information
somatic sensory information
visceral motor information
visceral sensory information

Answer 1

somatic sensory information

Remember that this information comes from the environment.

Question 2

Visceral sensory information is distributed primarily to reflex centers in the __________.

brain stem and diencephalon
skeletal muscles
cerebral cortex
cerebellar hemispheres

Answer 2

brain stem and diencephalon

Remember that this information is usually outside of your conscious awareness.

Question 3

The efferent division of the nervous system that includes nuclei, motor tracts, and motor neurons controls __________.

the central nervous system
peripheral effectors
visceral sensory information
the brain stem and diencephalon

Answer 3

peripheral effectors

Remember that these structures are involved with changing the outside environment.

Question 4

The motor neurons and pathways that control skeletal muscles form the __________.

central nervous system
autonomic nervous system
somatic nervous system
afferent division of the nervous system

Answer 4

somatic nervous system

Remember that this division is under volitional control.

Question 5

Judith is receiving messages in her brain from baroreceptors in the stomach, chemoreceptors detecting PO2 levels in the blood, and tactile receptors in the skin. All this information must be transmitted in what type of format to be detected by the central nervous system (CNS)?

perception
sensations
action potentials
pain

Answer 5

action potentials

What is the disturbance in a neuron’s cell membrane that is detected as a “signal”?

Question 6

Free nerve endings can be stimulated by many different stimuli because they exhibit little __________.

receptor specificity
ability to initiate transduction
accessory structures
information about the location of a stimulu

Answer 6

receptor specificity

Remember that these receptors detect very general sensations.

Question 7

The receptors that provide information about the intensity and rate of change of a stimulus are called __________.

phasic receptors
tonic receptors
receptor potentials
generator potentials

Answer 7

phasic receptors

Remember that these receptors are normally inactive.

Question 8

Amyotrophic lateral sclerosis (ALS) is a degenerative disorder that affects __________.

nociceptors and their associated sensory neurons
neurons of the reticular activating system
neurons of the prefrontal cortex
motor neurons and their associated skeletal muscles

Answer 8

motor neurons and their associated skeletal muscles

Question 9

Nociceptors, common in the skin, in joint capsules, and around the walls of blood vessels, are sensory receptors for __________.

temperature
chemical concentration
physical distortion
pain

Answer 9

pain

Remember that this a general way to prevent injury.

Question 10

Which of the following receptors are stimulated when a stiff breeze blows across the skin of your arm and moves some of the hairs?

lamellated corpuscles
Ruffini corpuscles
root hair plexuses
Golgi tendon organs

Answer 10

root hair plexuses

Question 11

Thermoreceptors are phasic receptors because they are __________.

unaffected by the temperature sensations
very active when the temperature is changing
inactive when the temperature is changing
slow when adapting to a stable temperatture

Answer 11

very active when the temperature is changing

Remember that these receptors are normally inactive.

Question 12

Tactile receptors provide sensations of __________.

joint and muscle movement
conscious perception of pain
touch, pressure, and vibration
pressure changes in the walls of blood vessels

Answer 12

touch, pressure, and vibration

Question 13

Which type of receptor detects volumes of digestive materials in the colon?

thermoreceptor
proprioceptor
baroreceptor
chemoreceptor

Answer 13

baroreceptor

Remember that this receptor is embedded in the walls of vessels and hollow organs.

Question 14

Chemoreceptors in the medulla oblongata would be sensitive to changes in pH and PCO2 in __________.

venous blood supply
lymph
aortic blood supply
cerebrospinal fluid

Answer 14

cerebrospinal fluid

Remember that this fluid circulates only in the central nervous system (CNS).

Question 15

The three major somatic sensory pathways are the __________.

posterior column, spinothalamic, and spinocerebellar
first-, second-, and third-order
nuclear, cerebellar, and thalamic
anterior, posterior, and lateral spinothalamic

Answer 15

posterior column, spinothalamic, and spinocerebellar

Remember that these signals originate in the skin and musculature.

Question 16

The axons of the posterior column ascend within __________.

the posterior and lateral spinothalamic tracts
the posterior and interior spinocerebellar tracts
the fasciculus gracilis and fasciculus cuneatus
all of the listed tracts

Answer 16

the fasciculus gracilis and fasciculus cuneatus

Question 17

Why does the sensory homunculus appear distorted in the face and hands?

It is a representation of the number of prefrontal cortex neurons needed to manipulate those given areas.
It is a representation of the number of sensory neurons in the given body areas.
It is a representation of the number of motor neurons associated with the given areas of the body.
It is a representation of where the special sense organs are located.

Answer 17

It is a representation of the number of sensory neurons in the given body areas.

Remember that these areas are highly innervated relative to other areas of the body.

Question 18

Ruffini corpuscles and Golgi tendon organs are similar in their __________.

location between a skeletal muscle and a tendon
ability to detect tension and distortion
both being thermoreceptors
structure

Answer 18

ability to detect tension and distortion

Question 19

The integrative activities performed by neurons in the cerebellar cortex and cerebellar nuclei are essential to the __________.

voluntary control of smooth and cardiac muscle
precise control of voluntary and involuntary movements
involuntary regulation of posture and muscle tone
involuntary regulation of autonomic functions

Answer 19

precise control of voluntary and involuntary movements

Remember that these activities are finely tuned.

Question 20

A sensory first-order neuron traveling along the posterior column pathway from the arm would synapse in the __________.

nucleus cuneatus
reticular activating system
nucleus gracilis
arbor vitae of the cerebellum

Answer 20

nucleus cuneatus

Question 21

The upper motor neuron of a somatic motor pathway has a cell body that lies in __________.

a nucleus of the spinal cord
an area outside the central nervous system (CNS)
a central nervous system (CNS) processing center
a nucleus of the brain stem

Answer 21

a central nervous system (CNS) processing center

Remember that this is an association area.

Question 22

The three integrated pathways controlling conscious and subconscious motor commands in skeletal muscle are the __________.

cerebellum, corticospinal, and reticulospinal
corticospinal, medial, and lateral
vestibulospinal, tectospinal, and reticulospinal
corticobulbar, tectospinal, and rubrospinal

Answer 22

corticospinal, medial, and lateral

Question 23

The motor tracts in the spinal cord controlling subconscious regulation of balance and muscle tone are the __________.

tectospinal tracts
reticulospinal tracts
vestibulospinal tracts
corticobulbar tracts

Answer 23

vestibulospinal tracts

Question 24

The background patterns of movement involved in voluntary motor activities are controlled by the __________.

vestibular nuclei
basal nuclei
superior and inferior colliculi
pyramidal system

Answer 24

basal nuclei

Remember that dysregulation in this area is a problem in Parkinson’s disease.

Question 25

The center of somatic motor control that plans and initiates voluntary motor activity is the __________.

cerebellum
cerebral cortex
basal nuclei
hypothalamus

Answer 25

cerebral cortex

Question 26

The center of somatic motor control that coordinates complex motor patterns is the __________.

cerebellum
cerebral cortex
thalamus
medulla oblongata

Answer 26

cerebellum

Remember that this is where the arbor vitae is located.

Question 27

The center of somatic motor control that controls basic respiratory reflexes is the __________.

medulla oblongata
mesencephalon
cerebrum
cerebellum

Answer 27

medulla oblongata

Remember that this is part of the brain stem.

Question 28

If a tract name begins with spino-, it must start in the __________.

spinal cord and end in the brain, bearing motor commands
spinal cord and end in the brain, carrying sensory information
brain and end in the peripheral nervous system (PNS), bearing motor commands
spinal cord and end in the peripheral nervous system (PNS), carrying sensory information

Answer 28

spinal cord and end in the brain, carrying sensory information

Question 29

If the name of a tract ends in -spinal, its axons must __________.

start in the spinal cord and end in the brain, carrying sensory information
start in the higher centers and end in the spinal cord, bearing sensory information
start in the higher centers and end in the spinal cord, bearing motor commands
start in the spinal cord and end in the peripheral nervous system (PNS), carrying motor commands

Answer 29

start in the higher centers and end in the spinal cord, bearing motor commands

Question 30

The posterior column pathway receives sensations associated with which of the following?

pain and temperature
highly localized fine touch, pressure, vibration, and position
crude touch and pressure
All of the listed responses are correct.

Answer 30

highly localized fine touch, pressure, vibration, and position

Remember that there is high specificity associated with these sensations.

Question 31

In the thalamus, data arriving over the posterior column pathway are integrated, sorted, and projected to the __________.

peripheral nervous system (PNS)
spinal cord
primary sensory cortex
cerebellum

Answer 31

primary sensory cortex

Remember that this is the main reception center for signals when they first arrive in the central nervous system (CNS).

Question 32

If a sensation arrives at the wrong part of the sensory cortex, you will __________.

experience pain in the posterior column pathway
be incapable of experiencing pain or pressure
reach an improper conclusion about the source of the stimulus
lose all capability of receiving and sending information

Answer 32

reach an improper conclusion about the source of the stimulus

Remember that this can lead to distortions in your perception.

Question 33

If the primary sensory cortex were damaged or the projection fibers cut, a person would be able to detect light touch but would be unable to determine __________.

the amount of pressure
the magnitude of the stimulus
the source of the stimulus
All of the listed responses are correct.

Answer 33

the source of the stimulus

Remember that this is an identification.

Question 34

The spinothalamic pathway relays impulses associated with __________.

crude sensations of touch, pressure, pain, and temperature
the position of muscles, tendons, and joints
proprioceptive information and vibrations
fine touch, pressure, vibration, and proprioceotion

Answer 34

crude sensations of touch, pressure, pain, and temperature

Remember that these sensations are not associated with precision.

Question 35

The spinocerebellar pathway includes the __________.

anterior and posterior tracts
gracilis and cuneatus nuclei
lateral and anterior tracts
lateral and posterior tracts

Answer 35

anterior and posterior tracts

Remember that these are ascending paths.

Question 36

The spinocerebellar pathway carries information concerning the __________.

pressure on each side of the body
position of muscles, tendons, and joints to the cerebellum
sensations of touch, pain, and temperature
sensations that cause referred and phantom limb pain

Answer 36

position of muscles, tendons, and joints to the cerebellum

Remember that this relates to position of the body in space.

Question 37

Somatic motor pathways always involve __________.

an upper and lower motor neuron
a ganglionic and preganglionic neuron
anterior and lateral nuclei
sensory and motor fibers

Answer 37

an upper and lower motor neuron

Remember that these are volitional pathways.

Question 38

Voluntary and involuntary somatic motor commands issued by the brain reach peripheral targets by traveling over the __________.

spinothalamic tracts
ganglionic and preganglionic fibers
sensory and motor fibers
pyramidal and extrapyramidal systems

Answer 38

pyramidal and extrapyramidal systems

Remember that these are descending pathways.

Question 39

The primary goal of the vestibular nuclei is __________.

regulation of reflex activity
maintaining posture and balance
the triggering of visual and auditory stimuli
controlling involuntary eye movements

Answer 39

maintaining posture and balance

Remember that this involves receptors in the inner ear.

Question 40

The reticulospinal tract is involved with __________.

regulation of involuntary reflex activity and autonomic functions
involuntary regulation of balance and posture
regulation of balance and muscle tone
regulation of voluntary motor control of skeletal muscles

Answer 40

regulation of involuntary reflex activity and autonomic functions

Remember that axons of upper motor neurons in the reticular formation descend in this tract.

Question 41

An individual whose primary motor cortex has been destroyed retains the ability to walk and maintain balance, but the movements __________.

are under involuntary control and are poorly executed
lack precision and are awkward and poorly controlled
are restricted and result in partial paralysis
are characteristic of involuntary motor commands

Answer 41

lack precision and are awkward and poorly controlled

Think about the effects of fewer neural cells in a network.

Question 42

The basal nuclei contain two populations of neurons. Neurons in the first group release acetylcholine (ACh), which has __________ effect on the neurons they synapse with; neurons in the second group release gamma aminobutyric acid (GABA), which has __________ effect.

an excitatory; an inhibitory
an inhibitory; an excitatory
a hyperpolarizing; a depolarizing
an excitatory; an excitatory

Answer 42

an excitatory; an inhibitory

Remember that these are opposing actions.

Question 43

When someone touches a hot stove, the rapid, automatic, preprogrammed response that preserves homeostasis is provided by the __________.

spinal reflex
primary sensory cortex
cerebellum
cerebral cortex

Answer 43

spinal reflex

Remember that this is a very simple response.

Question 44

Which part of the brain is responsible for the highest level of motor command in terms of complexity and voluntary motion?

primary motor cortex
primary sensory cortex
visual cortex
cerebellum

Answer 44

primary motor cortex

Question 45

“Itch spots” can be found in all EXCEPT which of the following areas of the body?

inner surface of eyelids
nasal mucous membranes
trachea
skin

Answer 45

trachea

Remember that this area is not accessible to actual scratching.

Question 46

Which of the following terms refers to a number of disorders affecting voluntary motor performance that may be caused by trauma during birth?

paresthesia
aphasia
anencephaly
cerebral palsy

Answer 46

cerebral palsy

Question 47

A condition in which the brain of a newborn infant has failed to develop is called __________.

aphasia
anesthesia
anencephaly
hypesthesia

Answer 47

anencephaly

Question 48

A person demonstrating anesthesia in a given area has lost __________.

sensation of touch
sensation of pressure
sensitivity to pain and temperature
sensation of touch, sensation of pressure, and sensitivity to pain and temperature

Answer 48

sensation of touch, sensation of pressure, and sensitivity to pain and temperature

What is the range of stimuli that can be detected in general receptors?

Question 49

An individual would lose two-point discrimination at 3–5 mm on which region or regions of the body?

fingertips
backs of hands and feet
tongue
lips

Answer 49

backs of hands and feet

Remember that the smaller the region, the more innervation is present in the area.

Question 50

Which of the following correctly defines referred pain?

pain generalized all over the body, such as the pain accompanying a fever
pain felt as being received from an amputated limb
pain felt in an uninjured body area when the injury has actually occurred in another location
pain localized to a specific, small area of the body where injury has occurred

Answer 50

pain felt in an uninjured body area when the injury has actually occurred in another location