Spinal tracts Flashcards
Describe the process/function of the corticospinal tract…
1) Signal (upper motor neuron) begins in the cerebral cortex
2) Travels down through brainstem (mid-brain, Pons, medulla)
3) Axons desiccate (contralaterally) at the bottoms of the medulla.
4) Travel down spinal cord and synapse with lower motor neurons to control skeletal muscle
Describe the process/function of the corticobulbar tract…
1) Signal begins in cerebral cortex
2) Axons travel to LMN in brain stem (both ipsilateral and contralateral)
3) LMN control muscles of face, head and neck.
What is hyper-reflexia and what does it indicate?
- An increased muscle stretch reflex (MSR)
- Abnormality/issue with the UMN of the corticospinal tract
What is clonus and what does it indicate?
- Causes rhythmic contraction of antagonistic muscles
- Linked to hyper-reflexia
What is Hypertonia?
- Increased tone of skeletal muscles
- UMN dysfunction
What is extensor-plantar response?
- When bottom of foot is ‘stimulated’ (scraped), toes extend instead of flexing
- AKA
Explain the spinothalemic pathway?
1st order neuron - sensory cell body of DRG
2nd order neuron - cell body in dorsal horn
3rd order neuron - Cell body in the thalamus
Crude touch is processed in which part of the spinothalamic tract?
Ventral spinothalemic tract
Pain and temperature are processed in which part of the spinothalamic tract?
Lateral spinothalemic tract.
Upon reaching the thalamus, sensory information is generally processed where?
In the somatosensory cortex.
Spinothalemic damage primarily results in what?
Loss senses such as; - Touch - Pain - temperature (in the contralateral side)
At what neuron order does the spinothalemic tract desiccate?
1st -> 2nd
What is the arrangement of the upper and lower pathways in the dorsal column pathway?
U - L - L - U
At which neuron does the dorsal column pathway decussate?
2nd order neuron, below the medulla oblongata.
Dorsal column damage can result in a loss of what?
Touch, proprioception and vibration in the ipsilateral side.
