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Lateral Corticospinal Tract
- Origin- primary motor cortex, supplementary motor cortex
- Pyramidal Cells in Corona radiate and narrow in the Internal Capsule
- Goes through the basis pedunculi (midbrain), then
- pontine nuclei (pons), then
- through the pyramids in the medulla and cross over,
- 75 to 90 % of the lateral corticospinal tract crosses over.
- Termination- intermediate zone and ventral horn
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Ventral Corticospinal Tract
- Origin- primary motor cortex, supplementary motor cortex
- Pyramidal Cells in Corona radiate and narrow in the Internal Capsule,
- goes through the basis pedunculi (midbrain), then
- pontine nuclei (pons), then
- through the pyramids (medulla)
- continues down in the ventral column of spinal cord in white matter
- Termination- ventral horn motor neurons, intermediate zone interneurons, collaterals may cross ( does not extend beyond thoracic spinal cord)
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Rubrospinal Tract
- Origin- red nucleus (midbrain) crosses in the ventral tegmental,
- descends in dorsolateral portion of midbrain:
- it travels with corticospinal tract in the lateral column
- Termination- lateral portions of intermediate zone and ventral horn
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Reticulospinal Tract
- Origin- Medulla (medullary) or pons (pontine)
- medullary reticulospinal tract travels in lateral column and the pontine reticulospinal tract travels in ventral column
- Termination- medial intermediate zone and ventral horn.
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Vestibulospinal Tract
- Origin- lateral vestibular nucleus and medial vestibular nucleus
- some fibers from the medial vestibular nucleus cross at the medulla,
- the lateral vestibular tract and the medial vestibular nucleus tract travel in ventral column
- Termination- medial intermediate zone and ventral horn
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Tectospinal Tract
- Origin- superior colliculus (midbrain),
- fibers cross at midbrain, it
- travels in ventral column of spinal cord
- Termination- medial intermediate zone and ventral horn
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Dorsal column-medial lemniscal pathway (Ascending (sensory) Tracts
- Origin- peripheral receptor
- sensory neuron fibers travel in dorsal column white matter
- sensory neuron synapses with brainstem neuron
- brainstem neuron cross, then travels in medial lemniscus before synapsing with thalamic neuron
- thalamic neuron projects to primary somatosensory cortical neuron
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Spinothalamic Tract (Ascending sensory Tracts)
- Origin- peripheral receptor
- sensory neuron synapses with dorsal horn neuron
- dorsal horn axon cross then travels in spinothalamic tract before synapsing with thalamic neuron
- thalamic neuron projects to primary somatosensory cortical neuron
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