Lecture 3 - Cerebral Cortex Flashcards
What is the size of the basic microcolumn for cerebral cortical functions?
~50µm
Which neuron is centered for the basic microcolumn for cerebral cortical function?
Pyramidal cells
How many layers is the neocortex?
6
How thick is the neocortex?
2-4 mm THIN
What is the first layer of the neocortex?
molecular layer
What is the second layer of the neocortex?
external granular layer
What is the third layer of the neocortex?
external pryamidal layer
What is the fourth layer of the neocortex?
internal granular layer
What is the fifth layer of the neocortex?
internal pryamidal layer
What is the sixth layer of the neocortex?
multiform layer
What is the central neuron of the neocortex?
somata with a pryramidal shape
How many somata are there in the central neuron of the neocortex? What is their shape?
Various sizes with fixed numbers
What are the cells in M1 in the neocortex called?
Betz cells
What do Betz cells do?
largest/main cells in the primary motor cortex
What kind of neurotransmitters are glutamate and aspartate?
EXCITATORY
What does it mean to be excitatory?
activate next neuron in the CNS
What do interneurons do in the neocortex?
process/integrate AFFERENT information
What kind of neurotransmitter is GABA?
inhibitory
What is the most outer layer of the neocortex?
Molecular layer
What is the deepest layer of the neocortex?
multiform layer
Where are the granular layers of the neocortex?
II and IV
Where are the pryamidal layers of the neocortex?
III and V
What lobe doesnt have a thick granular layer?
Frontal lobe (MOTOR LOBE)
What lobe has a thick layer of granular cells?
Parietal and occipital lobes
What do the afferent interneurons do in the neocortex?
provide feedback to pyramidal cells to regulate or modify the functions of the pyramidal cells
What is the ratio of pyramidal cells to interneurons in the cerebral cortex?
4:1
What do interneurons do in the neocortex?
don’t have large cell bodies but have dendrites that either ascend transverse or descend in the 6 layers
What layer has the outer band of Baillarger?
4
How is the outer band of Baillarger formed?
Through projection fibers in thalamus, axons ascend and go horizontally in layer 4
What layer has the inner band of baillarger?
5 mainly
What makes up the inner band of baillarger?
many pyramidal cell axons, horizontally descend out to subcortical structures
Where is the OUTER band of Baillarger from?
Thalamus
Where is the inner band of baillarger going?
among cortical regions and to other subcortical structures
What is the diameter of the microcolumn?
50 µm
How many neurons are in the micro column?
100 neurons, include pyramidal cells and interneurons
What type of fibers are pyramidal cells in the center?
efferent fibers
What makes up the first three layers of the commnicating fibers?
Association fibers and commissure fibers
Where are the projection fibers in the neocortex?
layers 4-6