L06 Sensory Pathways Flashcards
which of the 5 sensory modalities does not go through the thalamus?
smell
which senses does the spinothalamic tract serve?
nociception
temperature
crude touch
which senses does the dorsal columns/medial lemniscus pathways serve?
light touch
proprioception
vibration
postcentral gyrus is for what?
1º somatosensory cortex
precentral gyrus is for what?
1º motor cortex
where is the primary gustatory cortex?
inferior region of the postcentral gyrus
where is the primary auditory cortex?
transverse temporal gyri on superior surface of superior temporal gyrus
where is the primary visual cortex?
sup and inf to the calcarine fissure in the occipital lobe
where is the primary olfactory cortex?
uncus and amygdala
where are 1º sensory cell bodies for the body?
dorsal root ganglion
where are 1ºsensory cell bodies for the face?
trigeminal ganglion
where can you find the 2º sensory neuron bodies? where do their axons project?
in the dorsal horn or a brainstem nucleus. axons go to the contralateral thalamus.
the dorsal columns can be further divided into two symmetrical sets of what?
fasciculus cuneatus (lateral) fasciculus gracilis (medial)
name the route of spinothalamic tract
1º neuron cell body in DRG
2º neuron cell body in STT, and decussates very early on. axon project to:
3º neuron cell body in VP thalamus. axon projects to 1º SS ctx in postcentral gyrus
how are the cervical, thoracic, lumbar, and sacral segments arranged in the STT?
medial to lateral: C, T, L, S
what kind of neurons are 1º SS?
pseudounipolar
which sulci bound the fasciculus gracilis?
dorsal median and dorsal intermediate
which sulci bound the fasciculus cuneatus?
dorsal intermediate and dorsal lateral
fasciculus gracilis contains neurons for which part of the body?
lower body
fasciculus cuneatus contains neurons for which part of the body?
upper body
what is the medial lemniscus?
a collection of dorsal column axons that travels (post decussation) through the brainstem
at which spinal level does fasciculus cuneatus begin?
T6
the trigeminal nucleus has which three nuclei?
mesencephalic
chief sensory
spinal trigeminal
what does the mesencephalic nucleus do?
1º SS neurons
proprioception from jaw
reflex arc with masticator nucleus of V
what does the chief sensory nucleus do?
2º SS neurons
encodes touch/vibration info DC/ML
what does the spinal trigeminal nucleus do?
2º SS neurons
encodes noc/temp info STT
continuous with dorsal horn of spinal cord
