7. Movement

Question 1

After acetylcholine causes a flexor muscle to move your hand toward your shoulder, what would move it the other direction?

a. A different transmitter causes the muscle to relax.
b. A different transmitter causes the muscle to move the other direction.
c. Acetylcholine causes the extensor muscle to contract.
d. A different transmitter causes the extensor muscle to contract

Answer 1

c. Acetylcholine causes the extensor muscle to contract.

Question 2

What happens to a fish’s movement speed in colder water?

a. The fish swims more slowly.
b. The fish swims at the same speed by making each muscle contract more strongly.
c. The fish swims at the same speed by recruiting more white muscle fibers.
d. The fish swims faster.

Answer 2

c. The fish swims at the same speed by recruiting more white muscle fibers.

Question 3

Which of the following is true of mammals’ slow-twitch muscle fibers?

a. Because they are aerobic, they are subject to rapid fatigue.
b. Because they are anaerobic, they are subject to rapid fatigue.
c. Because they are aerobic, they do not fatigue rapidly.
d. Because they are anaerobic, they do not fatigue rapidly.

Answer 3

c. Because they are aerobic, they do not fatigue rapidly.

Question 4

Which of the following describes a stretch reflex?

a. The receptor detects that a muscle is stretched, and sends a signal to contract it reflexively.
b. The receptor detects that a muscle is contracted, and sends a signal to stretch it reflexively.

Answer 4

a. The receptor detects that a muscle is stretched, and sends a signal to contract it reflexively.

Question 5

A muscle spindle and a Golgi tendon organ are both described as what?

a. Optic receptors
b. Metabolic receptors
c. Proprioceptors
d. Chemoreceptors

Answer 5

c. Proprioceptors

Question 6

A brief stimulation in the motor cortex, less than 50 ms, produces what kind of result?

a. Isolated muscle twitches
b. Contraction of a particular combination of muscles
c. Contraction of whatever muscles are necessary to produce a particular outcome
d. Contractions of different muscles that vary unpredictably from one trial to another

Answer 6

a. Isolated muscle twitches

Question 7

A half-second stimulation in the motor cortex produces what kind of result?

a. Isolated muscle twitches
b. Contraction of a particular combination of muscles
c. Contraction of whatever muscles are necessary to produce a particular outcome
d. Contractions of different muscles that vary unpredictably from one trial to another

Answer 7

c. Contraction of whatever muscles are necessary to produce a particular outcome

Question 8

When do the posterior parietal cortex, premotor cortex, and supplementary motor cortex become most active?

a. During the second or two in preparation for a movement
b. During the movement itself
c. During the second or two after a movement

Answer 8

a. During the second or two in preparation for a movement

Question 9

What does the antisaccade task measure?

a. Which brain areas are active during preparation for a movement
b. The role of mirror neurons in imitation behaviors
c. Someone’s ability to inhibit a movement
d. The relative contributions of the medial and lateral pathways in the spinal cord

Answer 9

c. Someone’s ability to inhibit a movement

Question 10

The lateral tract of the spinal cord controls ___. The medial tract controls ___.

a. peripheral movements on the contralateral side (relative to the side of the brain where the tract originated) . . . trunk movements bilaterally
b. peripheral movements on the ipsilateral side . . . trunk movements bilaterally
c. trunk movements bilaterally . . . peripheral movements on the contralateral side
d. trunk movements bilaterally . . . peripheral movements on the ipsilateral side

Answer 10

a. peripheral movements on the contralateral side (relative to the side of the brain where the tract originated) . . . trunk movements bilaterally

Question 11

Where does the medial corticospinal tract originate in the brain?

a. From the primary motor cortex
b. From the primary motor cortex plus the red nucleus
c. From many parts of the cortex, plus the tectum, reticular formation, and vestibular nucleus
d. From the somatosensory cortex

Answer 11

c. From many parts of the cortex, plus the tectum, reticular formation, and vestibular nucleus

Question 12

Alcohol intoxication produces clumsiness, poor aim, impaired voluntary eye movements, and slurred speech. Damage to what brain structure yields these same deficits?

a. Corpus callosum
b. Ventromedial hypothalamus
c. Cerebellum
d. Red nucleus

Answer 12

c. Cerebellum

Question 13

How are the parallel fibers arranged relative to the Purkinje cells?

a. They are parallel to them.
b. They are perpendicular to them.
c. They are arranged at random angles.

Answer 13

b. They are perpendicular to them.

Question 14

What is the probable role of the indirect pathway in the basal ganglia?

a. It is active when the animal is at rest.
b. It stimulates appropriate movements.
c. It inhibits inappropriate competing movements.
d. It produces imitation of other people’s movements

Answer 14

c. It inhibits inappropriate competing movements.

Question 15

Which of the following generally characterizes the movements that depend heavily on the basal ganglia?

a. Stimulus-triggered, and generally faster than self-initiated movements.
b. Stimulus-triggered, and generally slower than self-initiated movements.
c. Self-initiated, and generally faster than responses that a stimulus triggers.
d. Self-initiated, and generally slower than responses that a stimulus triggers.

Answer 15

d. Self-initiated, and generally slower than responses that a stimulus triggers.

Question 16

In what way, if at all, does basal ganglia activity relate to motivation?

a. The basal ganglia increase vigor of response depending on expected reward value.
b. The basal ganglia help to maintain constant behavior even when motivation is low.
c. The basal ganglia become active only when you are competing against someone else.
d. Basal ganglia activity has nothing to do with motivation.

Answer 16

a. The basal ganglia increase vigor of response depending on expected reward value.

Question 17

What kind of learning depends most heavily on the basal ganglia?

a. Learned movements that depend on precise timing
b. Motor habits that are difficult to describe in words
c. Learning to recall specific life events
d. Learning what foods to eat

Answer 17

b. Motor habits that are difficult to describe in words

Question 18

According to Libet’s study, what is the order of events in a voluntary movement?

a. People form an intention, then activity begins in the premotor cortex, and finally the movement starts.
b. People form an intention at the same time that activity begins in the premotor cortex, and a bit later, the movement starts.
c. Activity begins in the premotor cortex, and a bit later, people are aware of forming an intention, and finally the movement starts.
d. Activity begins in the premotor cortex, and a bit later, people are aware of forming an intention, and simultaneously the movement starts.

Answer 18

c. Activity begins in the premotor cortex, and a bit later, people are aware of forming an intention, and finally the movement starts.

Question 19

What evidence suggests that people misperceive the time when they made a conscious decision?

a. People inaccurately report the time of a sensory stimulus.
b. An event shortly after the movement changes the reported time of the decision.
c. People who are more highly motivated report earlier decision times.

Answer 19

b. An event shortly after the movement changes the reported time of the decision.

Question 20

Parkinson’s disease results from damage to ______ releasing axons from the ______ to the striatum.

a. dopamine . . . substantia nigra
b. GABA . . . basal forebrain
c. norepinephrine . . . locus coeruleus
d. serotonin . . . raphe nucleus

Answer 20

a. dopamine . . . substantia nigra

Question 21

People with Parkinson’s disease show the greatest impairment with which type of movement?

a. Reflexes
b. Spontaneous voluntary movements
c. Movements in response to a stimulus
d. Movements when other people are around

Answer 21

b. Spontaneous voluntary movements

Question 22

In what way is L-dopa treatment for Parkinson’s disease unusual?

a. It produces behavioral benefits without entering the brain.
b. Unlike most drugs, it produces no unpleasant side effects.
c. The treatment becomes more and more effective over time.
d. It was based on a theory instead of trial and error.

Answer 22

d. It was based on a theory instead of trial and error.

Question 23

Transplant of brain tissue relieves Parkinson-type symptoms in laboratory animals, but so far this procedure has shown little benefit for humans. What is one reason?

a. Most patients with Parkinson’s disease are unwilling to try this procedure.
b. Laboratory animals have different neurotransmitters than humans do.
c. Surgeons use this procedure only in patients with an advanced stage of the disease.
d. It is difficult to place the transplant into the correct location.

Answer 23

c. Surgeons use this procedure only in patients with an advanced stage of the disease.

Question 24

What is the most common age of onset for Huntington’s disease?

a. Early childhood (3 to 7 years old)
b. The teenage years (13 to 19)
c. Middle age (30 to 50)
d. Old age (65 to 80)

Answer 24

c. Middle age (30 to 50)

Question 25

An examination of C-A-G repeats on one gene enables physicians to predict who will develop Huntington’s disease. What else does it help them predict?

a. What other diseases the person will get
b. The individual’s personality
c. The effectiveness of treatment
d. The age of onset of symptoms

Answer 25

d. The age of onset of symptoms

Question 26

Why do we move the eye muscles with greater precision than the biceps muscles?

Answer 26

Each axon to the biceps muscles innervates about a hundred fibers; therefore, it is not possible to change the movement by a small amount. In contrast, an axon to the eye muscles innervates only about three fibers.

Question 27

Which transmitter causes a skeletal muscle to contract?

Answer 27

Acetylcholine. And remember that a muscle’s only movement is to contract.

Question 28

In what way are fish movements impaired in cold water?

Answer 28

Although a fish can move rapidly in cold water, it fatigues easily.

Question 29

Duck breast muscles are red (“dark meat”), whereas chicken breast muscles are white. Which species probably can fly for a longer time before fatiguing?

Answer 29

Ducks can fly great distances, as they often do during migration. The white muscle of a chicken breast has the power necessary to get a heavy body off the ground, but it fatigues rapidly. Chickens seldom fly far.

Question 30

Why is an ultramarathoner like Bertil Järlaker probably not impressive at short-distance races?

Answer 30

An ultramarathoner builds up large numbers of slow-twitch fibers at the expense of fast-twitch fibers. Therefore, endurance is great, but maximum speed is not

Question 31

If you hold your arm straight out and someone pulls it down slightly, it quickly bounces back. Which proprioceptor is responsible?

Answer 31

The muscle spindle

Question 32

What is the function of Golgi tendon organs?

Answer 32

Golgi tendon organs respond to muscle tension and thereby prevent excessively strong muscle contractions.

Question 33

In what way does the brain anatomy facilitate communication between body sensations and body movements?

Answer 33

The motor cortex represents muscular control of body areas in close alignment to the way the somatosensory cortex, just posterior to the motor cortex, represents sensations from those areas.

Question 34

What evidence indicates that cortical activity represents the “idea” of the movement and not just the muscle contractions?

Answer 34

Activity in the motor cortex leads to a particular outcome, such as movement of the hand to the mouth, regardless of what muscle contractions are necessary given the hand’s current location.

Question 35

How does the posterior parietal cortex contribute to movement? The premotor cortex? The supplementary motor cortex? The prefrontal cortex?

Answer 35

The posterior parietal cortex is important for perceiving the location of objects and the position of the body relative to the environment. It is also active for planning of a movement. The premotor cortex and supplementary motor cortex are also active in preparing a movement shortly before it occurs. The supplementary motor cortex inhibits a habitual action when it is inappropriate. The prefrontal cortex stores sensory information relevant to a movement and considers possible outcomes of a movement.

Question 36

When expert pianists listen to familiar, well-practiced music, they imagine the finger movements, and the finger area of their motor cortex becomes active, even if they are not moving their fingers (Haueisen & Knösche, 2001). If we regard those neurons as another kind of mirror neuron, what do these results imply about the origin of mirror neurons?

Answer 36

These neurons must have acquired these properties through experience. That is, they did not enable pianists to copy what they hear; they developed after pianists learned to copy what they hear.

Question 37

What kinds of movements does the lateral tract control? The medial tract?

Answer 37

The lateral tract controls detailed movements in the periphery on the contralateral side of the body. (For example, the lateral tract from the left hemisphere controls the right side of the body.) The medial tract controls trunk movements bilaterally.

Question 38

What kind of perceptual task would be most impaired by damage to the cerebellum?

Answer 38

Damage to the cerebellum impairs perceptual tasks that depend on accurate timing.

Question 39

How are the parallel fibers arranged relative to one another and to the Purkinje cells?

Answer 39

The parallel fibers are parallel to one another and perpendicular to the planes of the Purkinje cells.

Question 40

If a larger number of parallel fibers are active, what is the effect on the collective output of the Purkinje cells?

Answer 40

As a larger number of parallel fibers become active, the Purkinje cells increase their duration of response.

Question 41

In general, do the basal ganglia have more effect on responses to a stimulus or on self-initiated movements?

Answer 41

The basal ganglia have more influence on self-initiated movements, which are generally slower.

Question 42

Which aspect of movement do the basal ganglia control?

Answer 42

The basal ganglia control the vigor of movements.

Question 43

What kind of learning depends most heavily on the basal ganglia?

Answer 43

The basal ganglia are essential for learning motor habits that are difficult to describe in words.

Question 44

Explain the evidence that someone’s conscious decision to move does not cause the movement.

Answer 44

Researchers recorded responses in people’s cortex that predicted the upcoming response. Those brain responses occurred earlier than the time people reported as “when they made the decision.”

Question 45

Is the genetic basis stronger for early-onset or late-onset Parkinson’s disease?

Answer 45

The genetic basis is stronger for early-onset Parkinson’s disease.

Question 46

How does MPTP exposure influence the likelihood of Parkinson’s disease? What are the effects of cigarette smoking?

Answer 46

Exposure to MPTP can induce symptoms of Parkinson’s disease. Cigarette smoking is correlated with decreased prevalence of the disease.

Question 47

How does L-dopa relieve the symptoms of Parkinson’s disease?

Answer 47

L-dopa enters the brain, where neurons convert it to dopamine, thus increasing the supply of a depleted neurotransmitter.

Question 48

In what ways is L-dopa treatment disappointing?

Answer 48

L-dopa increases dopamine activity in spurts and in all neurons, not steadily and not just in those that need help. It does not stop the loss of neurons. It has unpleasant side effects.

Question 49

Why is transfer of fetal tissue more successful in animal models of Parkinson’s disease than it is with human patients?

Answer 49

In laboratory animals, researchers use young animals at an early stage of the disease. In humans, this is an option when all else has failed, and as a result the patient already has extensive brain damage at the time of surgery.

Question 50

Why does damage to the basal ganglia lead to involuntary movements?

Answer 50

Output from the basal ganglia to the thalamus is inhibitory. After damage to the basal ganglia, the thalamus, and therefore the cortex, receive less inhibition. Thus, they produce unwanted actions.

Question 51

What procedure enables physicians to predict who will or will not get Huntington’s disease and to estimate the age of onset?

Answer 51

Physicians can count the number of consecutive repeats of the combination C-A-G on one gene on chromosome 4. If the number is fewer than 36, the person will not develop Huntington’s disease. For repeats of 36 or more, the larger the number, the more certain the person is to develop the disease and the earlier the probable age of onset.

Question 52

Identify Areas of Principal motor cortex

Answer 52