physiological psychology chapter 4

What is the difference between a sex-linked gene and a sex-limited gene?

A sex-linked gene is primarily related to X-linked genes, while a sex-limited gene is present in both sexes but only impacts one sex.

List the five major stages in the development of neurons in the CNS.

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

What occurs during the proliferation stage of neuron development?

Production of new cells and neurons, with some becoming stem cells and others migrating to form neurons and glia.

What guides the migration of neurons and glia to their locations?

Immunoglobulins and chemokines

What is synaptogenesis?

The process where synapses form between neurons.

Where have new neurons been found in adulthood?

New neurons have been found in areas such as the hippocampus.

What is apoptosis?

The process of getting rid of unnecessary neurons.

What type of chemical can prevent apoptosis?

A neurotrophin

What did Sperry observe in newts after damaging their optic nerve?

The optic nerve regrew in the correct direction, leading to the conclusion of a chemical trail guiding growth.

How does experience and training affect neuronal structures?

Experience and training can lead to changes in learning, brain development, and dendritic branching.

Name two ways a stroke can kill neurons.

By depriving them of oxygen and blood (ischemic stroke) or flooding them with excess blood (hemorrhagic stroke).

What is axon sprouting?

the process where new branches form on an axon to attach to vacant receptors on a postsynaptic neuron.

What is the role of neurotrophins after neuron damage?

They induce axons to form collateral sprouts and assist in the regrowth of new axons.

neurotrophins

chemical that promotes the survival of neurons. If a neuron is not exposed to neurotrophins, then it undergoes apoptosis

Apoptosis

a type of cell death

nerve growth factor (NGF)

a protein promotes the survival and growth of axons

sex-linked genes

x-linked genes

sex-limited genes

genes that are limited to a particular sex

four central nervous system that develop

hindbrain, midbrain, forebrain, and spinal cord

Fetal Alcohol Syndrome

• hyperactivity and impulsivity

• difficulty maintaining attention

• mental retardation

• motor problems and heart defects

• facial abnormalities

fine-tuning by experience

axons and dendrites modify throughout life

Blind brain adaptions

• increased activation in the occipital cortex

• use occipital lobe. to differentiate between tactical stimulaiton and braille symbols

focal hand dystonia

excessive practice leads to clumsiness, fatigue, and involuntary movement because of extensive reorganization of sensory thalamus and cortex so that the responses of each finger overlaps with another.

ischemic stroke

most common caused by blood clot or obstruction

hemorrhage

less frequent kind of stroke caused by a ruptured artery that floods neurons with excess blood, calcium, oxygen, and other chemicals.

edema

As a result of a stroke, there is an accumulation of fluid in brain that increases pressure on the grain and increases probability of strokes

disruption of sodium-potassium pump

leads to accumulation of potassium ions inside the neuron.

immediate medicinal treatment for strokes

tPA: medication that breaks up blood clots that must be administered quickly

cooling brain

minimizes damage after an ischemic stroke by reducting overstimulation, apoptosis, and inflammation

diaschisis

decreased activity of surviving neurons

after a stroke, destroyed cell bodies cannot be replaced

but damaged axons do grow back by following the myelin sheath.

axon sprouting

collateral sprouts renew branches from non-damaged axons that attach to vacant receptors, and cells that have lost their source of innervation release neurotrophins that induce axons to form collateral sprouts

denervation supersensitivity

heightened sensitivity to neurotransmitter after the destruction of an incoming axon. this can cause chronic pain

phantom limbs

cortex reorganizes itself after amputation by being responsive to other parts of the body