8.2 Brain Mechanisms Of Movement

Question 0

The motor cortex does not send messages directly to the muscles. It’s axons extend to the ____ and the ____, which generate the impulses that control muscles.

Answer 0

brainstem : spinal-cord

Question 1

Neuroscientists have known that direct electrical stimulation of the ____ ____ ____ – the precentral gyrus of the frontal cortex, just anterior to the central sulcus – elicits movements.

Answer 1

primary motor cortex

Question 2

The ____ ____ is particularly important for complex actions such as talking or writing.

Answer 2

cerebral cortex

Question 3

Each particular brain area in the motor cortex controls the structure on the ____ side of the body.

Answer 3

opposite

Question 4

The motor cortex orders an outcome and leaves it to the spinal-cord and other areas to find the right ____ of muscles.

Answer 4

combination

Question 5

The primary motor cortex is important for making movements but not for planning them. One of the first areas to become active is the ____ ____ ____.

Answer 5

posterior parietal cortex

Question 6

The posterior parietal cortex keeps track of the ___ of the ____ relative to the world. People with posterior parietal damage have trouble finding objects in space, even after describing their appearance accurately.

Answer 6

position of the body

Question 7

Beyond helping people control aim, the posterior parietal cortex is also important for ____ ____.

Answer 7

planning movements

Question 8

When they stimulate parts of the posterior parietal cortex, people frequently report an intention to ____ – such as an intention to move the left hand. After more intensive stimulation at the same locations, people report that they believe they did make the ____ – although, in fact, they did not.

Answer 8

move : movement

Question 9

The prefrontal cortex and the ____ ____ ____ are also important for planning and organising a rapid sequence of movements.

Answer 9

supplementary motor cortex

Question 10

The ____ ____ is most active immediately before a movement. It receives information about the target to which the body is directing its movement, as well as information about the bodies current position and posture. Both kinds of information are necessary to direct movement towards target.

Answer 10

premotor cortex

Question 11

The ____ ____, which is also active during a delay before a movement, stores sensory information relevant to a movement. It is also important for considering the probable outcomes of the possible movement.

Answer 11

prefrontal cortex

Question 12

If you had damage to the prefrontal cortex, many of your movements would be ____ or ____, such as showering with your clothes on or pouring water on the tube of toothpaste instead of the toothbrush.

Answer 12

illogical or disorganised

Question 13

The prefrontal cortex is inactive during ____, and actions we dream about doing are often as illogical as those of people with prefrontal cortex damage.

Answer 13

dreams

Question 14

Of discoveries the neuroscience, one of the most exciting to psychologists has been ____ ____, which are active both during preparation for a movement and while watching someone else perform the same or a similar movement.

Answer 14

mirror neurons

Question 15

These mirror neurons are theoretically exciting because of the idea that they may be important for ____ other people, identifying with them and imitating them.

Answer 15

understanding

Question 16

Mirror neurons in part of the ____ ____ become active when people smile or see someone else smile, and they respond especially strongly in people who report identified strongly with other people.

Answer 16

frontal cortex

Question 17

Mirror neurons are activated not only by seeing an action but also by any ____ of the action.

Answer 17

reminder

Question 18

Cells in the ____ ____ become active when you feel disgusted, see something disgusting, or see someone else show a facial expression of disgust.

Answer 18

insular cortex

Question 19

Mirror neurons develop their responses by ____.

Answer 19

learning

Question 20

Your motor cortex produces a kind of activity called a ____ ____ before any voluntary movement, and, on average, the readiness potential begins at least 500 ms before the movement.

Answer 20

readiness potential

Question 21

Studies have shown that the brain activity responsible for a movement apparently began ____ the person’s conscious decision. The results indicate your conscious decision does not cause your action. Rather, you became conscious of the decision after the process leading to the action has already been underway for about 300 ms.

Answer 21

before

Question 22

The studies have been controversial. One objection is it that perhaps people cannot ____ ____ the time they become conscious of something.

Answer 22

accurately report

Question 23

These studies suggests that what we identified as a ____ decision might be more the perception of an ongoing process than the cause of it.

Answer 23

conscious

Question 24

None of these results deny that you make a ____ ____. The implication however, is that your voluntary decision is, at first, unconscious.

Answer 24

voluntary decision

Question 25

Your decision to do something develops gradually and builds up to a certain strength before it becomes conscious. Evidently, voluntary is not ____ with conscious.

Answer 25

synonymous

Question 26

Messages from the brain must eventually reach the ____ and ____, which control the muscles. Diseases of the spinal-cord impair the control of movement in various ways.

Answer 26

medulla and spinal-cord

Question 27

Disorder: _____. Description: lack of voluntary movement in part of the body. Cause: damage to the spinal-cord, motor neurons, or their axons.

Answer 27

paralysis

Question 28

Disorder: _____. Description: loss of sensation and voluntary muscle control in both legs. Cause: cut through the spinal-cord above the segments attached to the legs.

Answer 28

paraplegia

Question 29

Disorder: ____. Description: loss of sensation and muscle control in all four extremities. Cause: Cut through the spinal-cord above the segments controlling the arms.

Answer 29

quadriplegia

Question 30

Disorder: _____. Description: loss of sensation and muscle control in the arms and legs on one side. Cause: cut halfway through the spinal-cord or (more commonly) damage to one hemisphere of the cerebral cortex.

Answer 30

hemiplegia

Question 31

Disorder: ____ ____. Description: impaired sensation in the legs and pelvic region, impaired leg reflexes and walking, loss of bladder and bowel control. Cause: late stage of syphilis. Dorsal roots of the spinal-cord deteriorate.

Answer 31

tabes dorsalis

Question 32

Disorder: ____. Description: paralysis. Cause: virus that damages cell bodies of motor neurons.

Answer 32

poliomyelitis

Question 33

Disorder: ____ ____ ____. Description: gradual weakness and paralysis, starting with the arms and later spreading to the legs. Both motor neurons and axons from the brain to the motor neurons are destroyed. Cause: unknown.

Answer 33

Amyotrophic lateral sclerosis

Question 34

Paths from the central cortex to the spinal-cord are called ____ ____. We are to such tracks, the lateral and medial corticospinal tracks.

Answer 34

corticospinal tracks

Question 35

The lateral corticospinal tract is a set of axons from the primary motor cortex, surrounding areas, and the ___ ____, a mid brain area that is primarily responsible for controlling the arm muscles.

Answer 35

red nucleus