Clinical correlates/notes from lecture Flashcards
sensory nervous system
afferent information conveyed from receptors in the periphery to the CNS
Motor nervous system
efferent information conveyed from the CNS to the skeletal, smooth and cardiac muscle
Somatic
body surface and musculoskeletal structures
Visceral
vessels, glands or organs containing smooth or cardiac muscle (ANS)
Efferent systems
Motor systems:
1) anatomically distinct sets of neurons
2) somatic is innervation of skeletal muscle
3) autonomic (Visceral) relates to innervation of smooth or cardiac muscle
Afferent systems
Sensory system
1) characterized by automically overlapping sets of neurons
2) somatic sensations are well localized
3) visceral sensations are poorly localized
LMN
have cell body in CNS and axon in PNS to innervate muscle fibers
Primary sensory neurons
have cell body in PNS with proximal process axon in CNS and distal process in PNS
Glia
the supportive cells
1) astrocytes in CNS
2) oligodendrocytes in CNS
3) microglia in CNS
4) Schwann cells in PNS
what are oligodendrocytes
Glia in CNS
myelin forming cells of the CNS
what are schwann cells
myelin forming cells of the PNS
Layers of the meninges
(closest to spinal cord) 1) pia mater
2) arachnoid matter (and subarachnoid space (CSF)
3) Dura Mater (underneath is potentail subdural space)
4) Epidural space for fat and veins
5) vertebra
Where are primary sensory neurons located in spinal cord?
Dorsal root (not cell bodies though)
What is the collect of PSC bodies located
Dorsal root ganglion
What is a spinal nerve?
combination of lower motor nuerons and primary sensory neurons.
what is the blood supply for the spinal cord?
Radicular arteries
Flexor withdrawal reflex
1) touch stimuli with primary sensory neuron
2) signal travels back to dorsal horn of spinal column
3) signal transfers to internuron that connects PSN to LMN in ventral horn
4) the LMN innervates the biceps to flex and withdraw hand
Fascicle
bundle of fibers by connective tissue
Epineurium
thick connective tissue that encloses the fascicles of the nerve
Endoneurium
delicates connective tissue the surrounds the nuerilemma cells
Perineurium
dense connective tissues that surround the axons of a single fasiicle. formed by flattened fiberglass like structures that act as a good barrier; tight junctions
what do the perinureim and epienurim form
a root sheath, or continuous barrier to the nerve bundles
what surrounds the ventral root in real life?
the dorsal root ganglion
Meningitis - possible diagnosis
patient refuses to raise leg