Nervous System Flashcards
Neuron
Cell body + dendrites + axon
Nerve
collection of neurons in PNS
ganglion
collection of cell bodies w/in nerve
Tracts
myelinated nerve fibers in CNS
Gray matter
cell bodies in CNS
Meninges around spinal cord
- Pia mater (deep)
- arachnoid mater
- Dura mater (outside)
Somatic nervous system
- conscious of
- one cell
- efferent = motor
- afferent = sensory
Autonomic nervous system
- two cell system
- sympathetic
- parasympathetic
- motor
- never travel w/ spinal nerves
Damage to CNS
- Axons don’t heal
2. Proximal stumps regenerate but stopped by astrocyte proliferation
Rhizotomy
Spastic paralysis
1. Tx: selectively cut posterior (sensory) root of affected nerve
Paresthesia
Pins and needles feeling
1. Caused by pressure on nerve
Crushing nerve injury
Kills axons distal to injury
1. Cell bodies usually survive and CT covering intact => regeneration
Anterograde (wallerian) degeneration
- Requires surgery
2. Cutting nerve injury
Saturday night syndrome
- Ischemia - Dec. blood supply
2. Permanent damage