Spinal nerves Flashcards
What do a) ascending and b) descending spinal tracts do?
a) carry sensory information up to the brain from the periphery
b) carry motor information away from the brain to the effector cells/ periphery
What does grey matter contain within the spinal cord?
Nerve cell bodies/ nuclei
Name the 2 types of ascending tracts and what type of sensory information they carry?
1) Spinothalamic tract- transmits pain, pressure, temperature and coarse touch
2) Dorsal columns - transmits discriminative/ fine touch and vibrations
what does white matter contain within the spinal cord?
Nerve cell axons - forming neurones
What are the two different spinal tracts within dorsal columns?
Where are they located in the spinal cord?
What information do they carry?
1) Fasciculus gracilis and Fasciculus cuneatus
2) Dorsal section of the white matter of the spinal cord
3) Sensory information from the lower body and upper body (respectively)
True/ False both the spinothalamic and dorsal columns 1 order neuron and 2nd order neuron synapse in the spinal cord?
False!
The dorsal column tracts 1st and 2nd order neurones synapse in the medulla
Where do sensory neurones decussate?
Which neurone is it that decussates?
1) Either in the spinal cord or medulla (depending if it’s spinothalamic/ dorsal column)
2) 2nd order neurones decussate
Where do sensory neurones decussate?
Which neurone is it that decussates? I
1) Either in the spinal cord or medulla (depending if it’s spinothalamic/ dorsal column)
2) 2nd order neurones decussate
What does decussate mean?r
Decussate means where neuronal fibres cross the spinal cord, passing through centres on the opposite side of the nervous system
Role of the pre and post central gyrus?
The pre central gyrus is responsible for motor information processing whilst the post central gyrus controls sensory info
What are corticospinal/ upper motor neurones?
What are lower motor neurones?
Corticospinal tracts carry motor information from the cortex to the spinal cord.
Lower motor neurones carry motor information from the spinal cord to the gland/ muscle effectors
How many neurones form the motor pathway?
Where do upper motor neurones decussate?
Motor pathways are formed by 1st and 2nd order neurones only
Upper motor neurones decussate in the brain stem/ spinal cord
How many neurones form the motor pathway?
Where do upper motor neurones decussate?
Motor pathways are formed by 1st and 2nd order neurones only
Upper motor neurones decussate in the brain stem/ spinal cord
What is a ganglion?
What types of ganglion are there?
A collection/ group of neuron cell bodies in the peripheral NS.
Dorsal root ganglion (found on 1st order spinal neurones) and trigeminal ganglion (found on 1st order cranial neurones)
