The Cortex Flashcards
Gyri
plural: singular = gyrus) -
- convolution or bump
- protruding rounded surfaces (folds)
- hills
Sulci
(plural: singular = sulcus)
- valley between gyri or enfolded regions that appears as surface lines (gaps between gyri)
Fissure
very deep sulcus
What do the sulci and gyri function in?
Sulci and gyri maximize surface area - triples area of the brain.
What is cortical folding correlated with?
The degree of cortical folding is correlated with intelligence.
Opossum has a very smooth brain, cats have more sulci and gyri, chimpanzees have lots of cortical folding
Bottlenose dolphins have even more cortical folding than us- maybe could be more intelligent than us
Corpus Callosum
Thick band of nerve fibers that connect the left and right hemispheres.
How are sulci and gyri created
Cortical material is folding in on itself and creating these valleys and hills
What is the cortex?
The wrinkly brain tissue outside of the brain
grey matter
dendrites and synapses
is made up of non-myelinated cells that have a layered appearance in cross section according to different cell types and groupings.
white matter
axons
is made up of myelinated axons or fiber tracts
Describe specializations of the human brain
- larger representations of the hands- we use tools
- neocortical specializations for speech- we can speak
- extreme hemispheric specialization- left hemisphere is dominant in speech
- expanded prefrontal cortex- executive area of brain is much larger
What does the cortex look like?
Very layered, rock like
Layers are different cell differentiation
Coretx generally had 6 layers but size and shape of cells and thickness of layers differs across brain regions.
Cytoarchitecture
the cellular composition of a bodily structure
- architecture of the cells
Longitudinal fissure
Also known as the interhemispheric fissure as it divides the 2 hemispheres
What is a myth
The myth that the left is dedicated to logic and right is creativity is not true
Left and right do control diff body movements
Language- left
Attention-right
Corpus Callosum
Thick band of nerve fibers that connect the left and right hemispheres.
What differs across species?
Proportions of brain also differ across species
Humans have way more brain devoted to neocortex than
- could be a indication of intelligence
What else is correlated with intelligence?
The proportion of frontal cortex to the rest of the brain is also thought to be correlated with intelligence.
What is on either side of the central sulcus?
we have the sensory cortex (somatosensory- touch feeling) and motor cortex
Brodman’s areas
Cytoarchitectonically defined regions (assigned numbers).
Cytoarchitectonics
cellular organization differs across regions.
What is Area 17?
primary visual cortex