PSYCH 454 Lecture Notes - Lecture 21: Sensory Cortex, Anosognosia, Frontal Lobe
24 May 2018
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Lect 21: Attention part 3
Pulvinar Helps Route Important Info Across Cerebral Cortex
●pulvinar= part of higher-order thalamus
; info from sensory organs = transmitted to
thalamus then to cortex
○Higher order thalamus: Most of thalamus that receives little or no info from
sensory organs; major input from cerebral cortex and provides strong output to
visual cortex
■Largest of these areas = pulvinar
○Connected with both V1 and V2 (or any other cortical areas) → indirect
connection between the two
●Directly connected cortical areas will be indirectly connected via the pulvinar (PUL)
●HOW BRAIN ACHIEVES COORDINATION BETWEEN FRONTOPARIETAL ATTN NETWORK
AND SENSORY CORTEX → manipulate information exchange and attention priority
Attention Increased the Activity of Pulvinar Neurons→ Increasing signal in cortex
●Attention @ RF (cued location)
○Increased response and activity (even across delay period) then longer/stronger
response to the target
●Attention away from RF→ little response across all
●Takeaways:
○Pulvinar neurons can differentiate between attention conditions
○Because of anatomical connectivity, pulvinar send AP to directly connected
cortical areas to increase excitability of both areas in coordinated areas
■Helps information transfer (more excitability = more likely to integrate
information and generate a response/ greater efficacy)
“Spatial Neglect”: condition that affects these pathways previously mentioned; what, when,
where and how
●Severe condition in which patients are not aware of one side of space (ex: left side of
space)
○Patients can even be unaware of large objects (including people)
○May not be aware that they have a deficit (anosognosia
)
●Mostly occurs after damage to right hemisphere (ex: after stroke)
○Right hemisphere (cf. left hemisphere) damage usually results in poorer
outcomes
●Commonly associated with damage to PPC
○But damage to other brain areas can also produce neglect (pulvinar, frontal lobe)
Document Summary
Pulvinar helps route important info across cerebral cortex. Pulvinar = part of higher-order thalamus ; info from sensory organs = transmitted to. Higher order thalamus: most of thalamus that receives little or no info from thalamus then to cortex sensory organs; major input from cerebral cortex and provides strong output to visual cortex. Connected with both v1 and v2 (or any other cortical areas) indirect connection between the two. Directly connected cortical areas will be indirectly connected via the pulvinar (pul) How brain achieves coordination between frontoparietal attn network. And sensory cortex manipulate information exchange and attention priority. Attention increased the activity of pulvinar neurons increasing signal in cortex. Increased response and activity (even across delay period) then longer/stronger response to the target. Attention away from rf little response across all. Pulvinar neurons can d ifferentiate between attention conditions. Because of anatomical connectivity, pulvinar send ap to directly connected cortical areas to increase excitability of both areas in coordinated areas.
