Module 4.2 Questions

Question 1

Which part of the neuron forms first, if either?

Answer 1

The axon forms first

Question 2

What is unusual about the olfactory receptors?

Answer 2

We continue forming new olfactory neurons throughout life.

Question 3

The 14C concentration in the atmosphere has been declining since 1963. The 14C concentration in neurons of a person’s cerebral cortex and olfactory bulbs corresponds to that of

Answer 3

the year of the person’s birth

Question 4

When Sperry cut a newt’s optic nerve and turned the eye upside down, what happened?

Answer 4

Axons of the optic nerve grew ack to their original target.

Question 5

If axons from the retina were prevented from showing spontaneous activity during early development, what would be the probable effect on development of thalamus?

Answer 5

the spinal cord makes an excess of neurons, but those that fail to innervate a muscle die.

Question 6

What is apoptosis?

Answer 6

A programmed mechanism of cell death.

Question 7

Which neurons depend on nerve growth factor to prevent apoptosis in early development?

Answer 7

Neurons in the sympathetic nervous system

Question 8

At what age does a person have the largest number of neurons

Answer 8

Before or shortly after birth

Question 9

If a pregnant women drinks alcohol, alcohol harms the brain of the fetus not only while it is in the system, but also while it is washing away after drinking. What is the danger while alcohol is washing away?

Answer 9

Overstimulation at glutamate synapses can poison the mitochondria

Question 10

In the ferret study, what evidence indicated that visual input to the auditory portions of the brain actually produced a visual sensation?

Answer 10

Ferrets that learned to turn one way in response to light in the normal eye turned the same way to light in the rewired eye.

Question 11

An enriched environment promotes growth of axons and dendrites in laboratory rodents. What is known to be one important reason for this effect?

Answer 11

Increased physical activity

Question 12

If a person is born blind, in what way do the senses of hearing and touch improve.

Answer 12

Through practice the person learns to increase attention to hearing and touch, and those sensations come to activate the occipital cortex.

Question 13

Of the following, which is the strongest evidence to indicate that musical training modifies brain anatomy?

Answer 13

At age 6, children starting musical training did not differ from average, but 15 months later they shoed enlargements of several brain areas.

Question 14

Many studies report brain changes after special experiences in adulthood, such as learning to juggle or learning to play golf. Why are some researchers skeptical of these findings>

Answer 14

Most of the reported results were small and have not been replicated.

Question 15

What causes musician’s cramp?

Answer 15

Rewiring of the cerebral cortex.

Question 16

Is it reasonable to argue that adolescents are mature enough to make some decisions and not others?

Answer 16

Perhaps, Adolescents reason in an immature way when they decide quickly under peer pressure.

Question 17

Immaturity of the prefrontal cortex is a possible explanation for which aspect of adolescent behavior?

Answer 17

Impulsivity

Question 18

Why do many older people continue to hold important jobs in spite of the declines in memory and brain function that are known to occur in old age?

Answer 18

The declines on average do not apply to all people

Question 19

What are the two kinds of stroke, and what causes each kind.

Answer 19

Ischemia (blocked blood vessel) and hemorrhage (burst blood vessel)

Question 20

The drug —— is helpful for strokes related to —–

Answer 20

tPA, ischemia

Question 21

Name two procedures that decrease the damage caused by strokes in laboratory animals, although physicians so far have seldom tried them with people.

Answer 21

Decreased body temperature and cannabinoids

Question 22

What is diaschisis?

Answer 22

Impaired performance of neurons because neurons that used to provide them with input have ben damaged.

Question 23

After someone has had a stroke, what kind of drug might be helpful, and which brain areas should receive it?

Answer 23

It would be best to deliver stimulant drugs to cells previously connected to the neurons that have been damaged.

Question 24

Where does collateral sprouting take place

Answer 24

in the axon

Question 25

Where does denervation supersensitivity take place?

Answer 25

In the dendrites

Question 26

What causes the phantom limb experience?

Answer 26

Reorganization of the sensory cortex

Question 27

Suppose a patient uses only right arm following injury that blocked all sensation from the left arm. Of the following which is the most promising therapy?

Answer 27

Tie the right arm behind the person’s back