N15 - Somatosensory (Tberry) Flashcards
4 subdivisions
S-I cortex
only 1 is seen on the surface
2 lies along postcentral sulcus
3a is gutter of central sulcus
3b lies along central sulcus
S-I thalamic inputs:
proprioceptors
3a
Position
S-I thalamic inputs:
tactile receptors
3b
Touch
S-I thalamic inputs:
Rapid adapting
Touch receptors
1
Texture
S-I thalamic inputs:
tactile receptors & proprioceptors
rapid & slow adapting touch receptors
2
Size & shape
most sensory informaiton enters what 2 areas of S-I cortex?
3a
3b
From thalamocortical inputs - VPL & VPM
tells us what we’ve been touched by
S-1: areas 1 & 2
S-1 somatotopy:
Complete, exquisite
3b
1
S-1 somatotopy:
Courser, cruder
3a
2
S-II cortex
parietal opercular cortex
sparse direct thalamic inputs
S-II
bilateral somatotopic map
S-II
(Different from S-I –> contains somatotopy for contralateral side only)
Place where serious processing takes place
5&7
Superior parietal lobule
area 5&7
Sorts out which stimuli are important at the time
Somatosensory association cx
aka - multimodal association cx
aka - brodman’s area 5 & 7
SI/SII
somatosensory
Premotor cx
motor plans
limbic system
motivation/emotion
vestibular system
body position
mental self-image
5 & 7
receives input from:
limbic, visual, auditory, vestibular systems
5 & 7
Multi-modal association
neglect syndrom
5 & 7
contralateral loss of all primary and secondary modalities to body areas represented in cortical area loss
primary somatosensory cortex
Loss of secondary modalities even in primary somatorsensory cortex is intact
(pt can feel touch, but not define what it is)
Superior parietal lobule lesion
