Ascending Sensory Pathways Flashcards
What type of information does the spinothalamic tract carry?
Crude touch, temperature, pressure and pain
Which sensory tract uses thin, poorly myelinated axons?
Spinothalamic
Which sensory tract uses thick, well myelinated axons?
Dorsal column
Does the spinothalamic pathway use fast or slow conduction?
Slow
Does the spinothalamic pathway run contralaterally or ipsilaterally in the spinal cord?
Contralaterally
Where do the primary neurons of the spinothalamic tract synapse?
Dorsal grey horn
Where do the secondary neurons of spinothalamic tract cross the midline?
Ventral white commissure (just anterior to central canal)
What is the spinothalamic tract called when it reaches the brainstem?
Spinal lemniscus
Where does the secondary neuron of the spinothalamic tract synapse?
Ventral posterolateral nucleus of the thalamus
What information passes through the medial VPL of the thalamus?
Sensory information from arm
What information passes through lateral VPL of the thalamus?
Sensory information from leg
Where do tertiary neurons of the spinothalamic tract terminate?
Primary somatosensory cortex
What type of information does the dorsal column pathway carry?
Discriminative touch, vibration and proprioception
Does the dorsal column pathway use fast or slow conduction?
Fast
Does the dorsal column pathway run contralaterally or ipsilaterally in the spinal cord?
Ipsilaterally
Where does the dorsal column pathway ascend in the spinal cord?
Ipsilateral gracile or cuneate fascicle
In the medulla, what are the gracile and cuneate fascicles renamed to?
Gracile and cuneate tubercles
Where do the primary neurons in the dorsal column pathway synapse?
Gracile/cuneate tubercle
Where do the secondary neurones of the dorsal column pathway cross the midline?
Internal arcuate fibres in medulla
Where do the secondary neurons of the dorsal column pathway ascend?
Medial lemniscus
Where do the secondary neurons of the dorsal column pathway synapse?
Ventral posterolateral nucleus of thalamus
Where do the tertiary neurons of dorsal column pathway project to?
Primary somatosensory cortex
In which pathway does sensation from the head travel?
Trigeminothalamic pathway
What facial sensation does trigeminal nerve carry?
General sensory from face, scalp and dura
What facial sensation travels in facial nerve?
External ear sensation
What facial sensation travels in glossopharyngeal nerve?
Sensation from posterior 1/3 of tongue, pharynx and middle ear
What facial sensation travels in vagus nerve?
Sensation from auditory canal, larynx, pharynx and oesophagus
What are the subdivisions of the trigeminal nucleus?
Mesencephalic, pontine/principal sensory and spinal
Which part of the trigeminal nucleus receives pain and temperature?
Caudal part of spinal nucleus
Which part of the trigeminal nucleus receives simple touch and pressure?
Rostral part of spinal nucleus
Which part of the trigeminal nucleus receives discriminative touch?
Pontine/principal sensory nucleus
Which part of the trigeminal nucleus receives proprioception?
Mesencephalic nucleus
In which pathways do the axons descend before ascending?
Trigeminothalamic
- pain and temperature
- touch and pressure
Where do fibres in the trigeminothalamic pathway descend?
Spinal tract
Where does information travelling in the trigeminothalamic pathway go to in the thalamus?
Ventral posteromedial nucleus
In which trigeminothalamic pathway are the primary neuron cell bodies not in their respective cranial nerve ganglia?
Proprioception pathway - cell bodies in mesencephalic nucleus
What reflex is associated with the proprioception pathway of the trigeminothalamic tract?
Jaw jerk reflex
