Flashcards in Spinal cord & reflexes Deck (67)
What fibres are present in the dorsal root?
Sensory afferent fibres
What fibres are present in the ventral root?
Motor efferent fibres
Where is the grey matter in the spinal cord?
Where is the white matter in the spinal cord?
In which horn are motor fibres found?
White mater is arranged in how many columns in the SC?
3 - posterior, lateral & anterior
What are the 3 important tracts in the SC?
What type of sensation does the spinothalamic fibres carry?
Pain & temperature
Where do fibres in the corticospinal tract originate?
Primary motor cortex
Where do lateral corticospinal fibres cross over?
How many neurons are present in descending motor pathways?
2 - upper & lower motor neurons
Where is the site of the lower motor neurone?
How many neurons are present in sensory ascending pathways?
3 - afferent sensory, medulla, thalamus
What type of sensation does the dorsal column carry?
Touch, vibration, pressure & proprioception
Where does the 2nd order neuron decussate in the ascending pathway?
What is another name for the ascending sensory tracts in the brain?
Where do neurons radiate from the thalamus in ascending pathways?
Post central gyrus
In the spinothalamic tract, where neurons cross over?
At the spinal level it enters
In the spinothalamic tract where does the 1st order neuronal synapse onto the 2nd order neuron?
What is a reflex?
An involuntary response to sensory stimuli
Where are reflexes mediated?
Name a monosynaptic reflex
Name a polysynaptic refelx
In the stretch reflex, stretching of the tendon causes what?
Contraction of the agonist (quad)
Inhibition of the flexor
What initiates reflexes?
What does the flexor reflex initiate?
Flexor activity (withdrawal)
Crossed extensor reflex - contraction of extensor on contralateral limb
Which neurons (UMN/LMN) mediate reflexes?
In an UMN lesion, what happens to reflexes?
What happens to tone in UMN lesions?