blood supply and spinal cord stuff

circle of willis

frontal lobe

lateral: middle cerebral artery

medial: anterior

inferior: middle and anterior

temporal lobe

lateral: middle cerebral artery

medial: middle and posterior

inferior: posterior

parietal lobe

lateral: middle cerebral artery

medial: anterior

occipital lobe

all surfaces: posterior cerebral artery

why can a stroke in the middle cerebral artery be so devastating?

the mca sends blood to important parts of the brain that control movement, so strokes in the mca can lead to disability or death

what is the blood brain barrier

it protects the brain from random bad things floating in the blood

how do tight junctions and astrocytes contribute to the bbb?

the junctions and astrocytes are packed so tightly together that nothing can pass through them

what is the point of having an incomplete bbb in some places?

splits in the bbb act as a sampling station for the third and fourth ventricles

where is the area postrema and what does it have to do with the bbb? explain how ingesting certain toxic substances involves the area postrema.

the area postrema makes you throw up. it is in the fourth ventricle. like the bbb, it helps keep toxins out of the body

what is the relationship between the spinal cord segments and spinal vertebrae? where does the spinal cord end?

spinal vertebrae surround the spinal cord. the spinal cord is split into hypothetical segments that help determine which nerves control certain parts of the body. the spinal cord ends around the lower back at the coccygeal section

how is the nomenclature of the spinal cord related to that of the spine?

what are dermatomes? name the ones on spinal cord

dermatome: body segments that align with the hypothetical segments of the spinal cord

from top to bottom: cervival, thoracic, lumbar, sacral, coccygeal

what is the cauda equina?

collection of nerves at the end of the spinal cord

Where is a lumbar puncture done? Why is it done there? Which meninges need to be punctured? How do lumbar punctures and epidurals differ?

lumbar puncture is usually done in L3 or 4.

this is where the actual spinal cords ends but there is still cerebrospinal fluid there for doctors to get a sample of.

the dura mater and arachnoid need to be pierced.

epidurals do not penetrate the dura mater.

what are the differences between a motor neuron and sensory neuron?

motor neuron: efferent (info from brain to to peripheral nervous system)

sensory neuron: afferent (info from pns to brain)

dorsal root ganglion

where the sensory neuron cell bodies are

dorsal and ventral roots of spinal nerves

dorsal: allow info to enter spinal cord (afferent)

ventral: allow info to exit spinal cord (efferent)

what causes the difference in amount of white and grey matter along the length of a spinal cord?

when there is more white matter, it means there are more axons from higher other sections of the spinal cord nearby

what are the two factors that determine the impairments of spinal cord injuries? explain how these affect the severity of the impairments

the two factors are the location and severity of the injury. the higher the spinal cord is damaged, the more likely it is that everything below it will be affected.

which level of damage means the person with spinal cord damager will require a ventilator?

above C3

difference between paraplegic and quadriplegic

paraplegic: have control over arms but not legs

quadriplegic: lost control over all four limbs

what are the top four causes of spinal cord injuries?

1. motor vehicle accidents like cars and motorcycles

2. falls

3. sports

4. violence

where do the sympathetic and parasympathetic nervous systems exit the spinal cord?

sympathetic: thoracic and lumbar

parasympathetic: cervical and sacral

what is the function of the sympathetic nervous system? what is the function of the parasympathetic nervous system?

sympathetic: fight or flight

parasympathetic: rest and digest

what is the most important practical information about getting the parasympathetic system more active that was mentioned in class?

to activate the parasympathetic system you can use breathing like meditation or box breathing