NeuroAnatomy_Unit3_Lec2 Flashcards
Somatic nervous system
Under voluntary control
Sensory neurons- receptors from the body walls and limbs (exteroceptors)
Motor neurons- innervate skeletal muscles
Autonomic nervous system
Involuntary system
Sensory neurons- interoceptors
output- regulates cardiac activity, smooth muscle, glandular tissues, and visceral reflexes
Pain afferent autonomic neurons
- ) what do they monitor
- ) where are the cell bodies
- ) how do they get to the brain
respond to internal stimuli such as excessive stretching, distension of the wall of the GI tract, lack of Oxygen and nutrients to cardiac muscle
cell bodies are in the dorsal root ganglia
Their afferent fibers are distributed with sympathetic motor fibers and travel to the brain.
Non-Pain afferent autonomic neurons
- ) what do they monitor
- ) where are the cell bodies
- ) how do they get to the brain
continually send signals to the brain, motoring and integrating visceral activities
cell bodies are in special nuclei in the brain
They are distributed with parasympathetic motor fibers (Their processes travel either with cranial nerves or in specific tracts within the spinal cord)
Referred pain
When pain is felt at a site other than that of the actual anatomical location of the problem.
Due to the visceral afferent fiber cell bodies being located in the same area as the somatic afferent fibers (which supply the dermatomes)
Sympathetic nervous system
fight or flight
Parasympathetic nervous system
rest and digest
Areas that receive only sympathetic input (most receive both sympathetic and parasympathetic)
cutaneous blood vessels, sweat glands, and hair shafts
Preganglionic neuron
Myelinated
Cell body-in the brain or spinal cord
axon- exits the CNS as part of a spinal or cranial nerve
Postganglionic neuron
Un-myelinated
cell body- in the PNS (cell body located in a Ganglion)
axon- terminates in a visceral organ
2 types of sympathetic ganglia
Paravertebral ganglia (lie in a row on either side of the vertebral column)
Prevertebral ganglia (lie anterior to the vertebral column, cervical level)
Parasympathetic ganglia
most are located close or within the wall of a visceral organ
Preganglionic Sympathetic Neurons
form a column in the intermedio-lateral horn (T1-L2), send their axons through the anterior/ventral root of the spinal cord.
white ramus communicant
the pathway from the intervertebral foramina to the sympathetic ganglia
found at every level btw T1-L2
T1-T4 sympathetic preganglionic neurons synapse in
Synapse in the paravertebral ganglia, and their postganglionic neurons supply the heart, lungs and smooth muscles of the bronchi
