Biological Psychology - Chapter 5

Front 1

What are the three main divisions of the brain?

Back 1

- Hindbrain
- Midbrain
- Forebrain

Front 2

What are the five stages in the development of neurons?

Back 2

1. Proliferation
2. Migration
3. Differentiation
4. Myelination
5. Synaptogenesis

Front 3

Who discovered 'nerve growth factor'?

Back 3

Rita Levi-Montalcini

Front 4

What happens if a neuron in the sympathetic nervous system does not receive enough nerve growth factor?

Back 4

If a neuron in the sympathetic nerve system does not receive enough nerve growth factor (NGF), it will die.

Front 5

What is 'apoptosis'?

Back 5

The death neurons are 'programmed' to undergo if they do not receive enough nerve growth factor (NGF).

Front 6

What type of chemical can prevent apoptosis?

Back 6

Neurotrophins

Front 7

What is another neurotrophin besides nerve growth factor?

Back 7

Brain-derived neurotropic factor (BDNF)

Front 8

What three functions do neurotrophins serve?

Back 8

- Prevent apoptosis
- Increase axonal branching
- Increase pain and regrowth of axon

Front 9

Describe the formation of the central nervous system in the embryo.

Back 9

A neural tube forms around a fluid filled cavity which develops into the hindbrain, midbrain, and forebrain. The fluid filled cavity becomes the central canal and the four ventricles.

Front 10

What did Weiss observe in his experiments on grafting extra limbs onto salamanders?

Back 10

After axons reached the muscles of the extra leg, that extra leg would move in synchrony with its neighbor. (1924).

Front 11

What principle did Weiss conclude directed the innervation of the extra limb? Is this principle still thought to be correct?

Back 11

Weiss concluded that axons attached to the new muscles at random and sent a variety of messages until they found a message that their muscle responded to. (1924). Later evidence supported the interpretation Weiss had rejeced: the salamander's extra leg moved in synchrony with its neighbor because each axon found exactly the correct muscle.

Front 12

What did Sperry observe when he damaged the optic nerve of newts?

Back 12

The severed optic nerves grew back and reconnected to the tectum; when this happened, the newts regained normal vision. (1943).

Front 13

What happened when he rotated a newt's eye by 180 degrees?

Back 13

The severed axons reformed their original connections instead of adapting to the eye's changed position. Because of this, the newt saw everything upside down and backward. (1943).

Front 14

What conclusion did Sperry's results suggest?

Back 14

Each severed axon regenerated to the area of the tectum where it had originally been by following a chemical trail.

Front 15

What is 'TOPdv'?

Back 15

TOPdv ("TOP" for topography; "dv" for dorsoventral) is a protein found in the tectum of amphibians.

Front 16

What is TOPdv's role in directing retinal axons to the tectum?

Back 16

As axons from the retinal axons with the greatest concentration of TOPdv connect to the tectal cells with the highest concentration of that chemical. Likewise, the axons with the lowest concentration connect to the tectal cells with the lowest concentration.

Front 17

Describe the principle of 'neural Darwinism'.

Back 17

During development, synapses form randomly before a selection process keeps some and rejects others, in addition to chemical guidance and trophic factors.

Front 18

What happens to axons that form active synapses?

Back 18

They receive nerve growth factor (NGF) that deactivates the program for apoptosis.

Front 19

What happens to axons that do not form active synapses?

Back 19

They undergo apoptosis (programmed cell death) because of a lack of nerve growth factor (NGF).

Front 20

Describe the effects of "environmental enrichment?"

Back 20

Environmental enrichment refers to the ability to redesign out brain in response to experience. This leads to enhanced dendritic branching and improved performance in animals and humans.

Front 21

What brain area is larger in professional musicians?

Back 21

Gray matter.

Front 22

What can we conclude about cause and effect in the relationship of brain size, musical ability, and experience?

Back 22

Practicing a skill reorganizes the brain to maximize performance of that skill.

Front 23

What area is larger in people who had extensive experience playing stringed instruments?

Back 23

The postcentral gyrus in the right hemisphere.

Front 24

What is "focal hand dystonia," and what is its physiological basis?

Back 24

"Focal hand dystonia" is a condition where the brain has reorganized itself so much that stimulation on one finger excites mostly or entirely the same cortical areas as another finger. This leads to fingers becoming clumsy, fatiguing easily, and making involuntary movements.

Front 25

Where are stem cells located in adult vertebrates?

Back 25

In a vertebrate's nose, because olfactory receptors generally have a half-life of only 90 days because they are exposed to the outside world and its toxic chemicals.

Front 26

Describe "fetal alcohol syndrome (FAS)."

Back 26

Caused by alcoholic consumption during pregnancy. Symptoms include decreased alertness, hyperactivity, facial abnormalities, and mental retardation.

Front 27

What are the effects of prenatal cocaine exposure?

Back 27

Slight decrease in IQ scores, and greater decrease in language skills.

Front 28

What are the effects of cigarette smoking during pregnancy?

Back 28

Prenatal exposure to cigarette smoking is associated with:
- low birth weight and other illnesses early in life
- Sudden infant death syndrome
- Long-term intellectual deficits
- Attention-deficit-hyperactivity disorder (ADHD)
- Impairment of the immune system
Delinquincy and crime later in life (sons esp.)

Front 29

What are the effects of thyroid definciency in adulthood? And in infancy?

Back 29

Thyroid deficiency in adulthood leads to lethargy; thyroid deficiency in infancy leads to mental retardation.

Front 30

What is the most common cause of brain damage in young people?

Back 30

Closed head injury.

Front 31

What are the two types of stroke and the cause of each?

Back 31

Types of Stroke (cerebrovascular accident):
1. Ischemia - most common type; caused by a blood clot.
2. Hemorrhage - bleeding due to rupture of an artery.

Front 32

In what two ways does a stroke kill neurons?

Back 32

1. Cells in vicinity die immediately.
2. Cells in penumbra may die in days because of Na- accumulation and edema (the accumulation of fluid).

Front 33

What are the five most common stroke symptons?

Back 33

1. - Sudden numbness or weakness of face, arm, or leg, especially on one side of the body.
2. - Sudden confusion, trouble speaking or understanding.
3. - Sudden trouble seeing in one or both eyes.
4. - Sudden trouble walking, dizziness, loss of balance or coordination.
5. - Sudden severe headache with no known cause.

Front 34

What are three treatments that may minimize damage from a stroke?

Back 34

1. - In treating ischemic strokes, a drug called "tissue plasminogen activator (tPA)" is effective in breaking up blood clots. However, treating a hemorrhagic stroke with a tPA would only make matters worse.
2. - Cooling the patient's brain to about 91 - 97 F for the first three days after a stroke.
3. - Cannibinoids.

Front 35

What is "disuse sensitivity?"

Back 35

Disuse sensitivity: Heightened sensitivity as a result of inactivity by an incoming axon.

Front 36

What is the "Kennard principle?"

Back 36

Kennard principle: recovery from brain damage early in life is more extensive than after similar damage later in life.

Front 37

What is "denervation supersensitivity?"

Back 37

Denervation supersensitivity: Heightened sensititivty to a neurotransmitter after the destruction of incoming axons.

Front 38

What is "diaschisis?"

Back 38

Diaschisis: refers to the decreased activity of surviving neurons after damage to other neurons.

Front 39

What are "collateral sprouts?"

Back 39

Collateral sprouts: a newly formed branch from an uninjured axon attaches to a synapse vacated when another axon was destroyed. The brain is constantly losing old synapses and sprouting new ones to replace them.