Association Cortex Flashcards
What are the areas of cortex besides the primary sensory and motor areas?
association areas
What is the temporal association cortex specialized for?
visual forms, objects, textures
What is the parietal association cortex specialized for?
visuospatial awareness (attention), visuomotor transformations (intention), somethesis
What is the frontal association cortex specialized for?
spatial and object working memory, planning, withholding responses
How can you see how association cortices are organized?
staining
How many layers do association areas have?
at least 5, usually 6
Where do layers 1 and 2 project?
other cortical areas
Where does layer 3 project?
other cortical areas and opposite hemisphere
What happens with lesions of the upper cortex? Does it affect descending pathways?
disrupts project within the cortex only, doesnt injure descending path
Where do layers 4 and 5 project?
subcortical structures (striatum, superior colliculus)
Where does layer 6 project?
thalamus
What layer does thalamic input go into?
layer 4
What is the ventral stream?
who/what pathway, in temporal lobe
What is the dorsal stream?
when/where pathway, in parietal lobe
Trace the dorsal stream
visual info from occipital–>posterior parietal–> dorsal prefrontal regions (spatial working memory) and dorsal premotor areas–> proximal muscles for reach
What does spatial working memory do?
remembers where target is, even if not visible anymore
Trace the ventral stream
visual info from foveal representation–>infratemporal cortex–>object working memory and ventral premotor area–>distal muscles for grasp
What does object working memory do?
remembers what somethign is even if you dont see it again
Where are face cells?
inferior temporal cortex
Where are mirror neurons located? What do they do?
in temporal lobe, association for learning, learn by imitation
What is agnosia?
impaired object recognition
What is achromatopsia?
impaired color recognition (part of ventral stream in V4)
What is prosopagnosia?
impaired face recognition
What is alexia?
impaired word recognition
What is receptive aphasia?
impaired word interpretation
What is expressive aphasia?
impaired word usage
What is apraxia?
impaired object utilization/tool use deficits
What drives cells in the parietal association areas?
attention to target for intention to go towards target
What does damage to parietal association area cause?
hemineglect
What activates the prefrontal cortex?
tasks that require generation of working memory
What is the physiological substrate of working memory?
activity in dorsolateral prefrontal area in working memory cells
What is metacognition? Where is it found?
integration of sensory info and pausing/withholding motor response if necessary and monitoring outcomes
done in prefrontal cortex
What does damage to the prefrontal cortex cause?
area-dependent deficits
can be emotional, cognitive, motor, oculomotor, verbal, problems withholding improper responses
What are syndromes with deficits in working memory and planning? Where are changes seen in brain?
schizophrenia, ADHD
don’t activate prefrontal cortex
