Cortex Flashcards
Cortex evolution
expanded the most over evolution, uniquely human
Outputs for 6 cortical layers
2: ipsilateral cortex
3: contralateral cortex (2/3 bigger in assoc. cortex)
5: brainstem/spinal cord (big in M1)
6: thalamus
Inputs for cortical layers
Thalamus: 4 (big in S1)
Brainstem: 2-6
Cortex: 1-5
3 ways to divide cortex
Anatomically = gyri/sulci
Cytoarchitecture = brodmann’s areas
Connectivity-based = association and function
Visual Network
Occipital lobe, inferior temporal does the what pathway (object recognition)
Somatomotor Network
M1/S1 work together
Dorsal Attention Network
determine motion of objects, where in space, guide eye movements to motion
Ventral Attention Network
Monitor enviro broadly, detect salient stimuli, shift attention
Limbic Network
Orbitofrontal cortex regulates emotions
Entorhinal cortex regulates memory
Control Network
Complex cognition, decisions, problems, numbers, hold info in mind
Mediates “battle” between default (think) and other networks (pay attention)
Default Mode Network
‘task-negative’, suppressed when doing anything
internal thought, current enviro, past/future, minds of others
medial prefrontal cortex
Association Fibers
communicate within hemisphere
Short range U-fibers
Long range
- superior longitudinal fasciculus = connects all lobes
- arcuate fasciculus = connect lang areas
- uncinate = connect limbic areas in temporal lobe to limbic frontal lobe
Commissural Fibers
communication between hemispheres
- corpus callosum
-anterior commissure = olfaction
posterior commisure = pupillary light reflex
Projection Fibers
communication with brainstem and body
- corona radiata
- internal capsule
-SC/lateral corticospinal tract
Cortex development
Grey matter peaks age 6 = prune after
Ventricular volume = rises in late adulthood, cells dying
White matter volume = peak young adulthood
Cortical thickness = peak age 1
