Cerebral Cortex Flashcards
What are the general functions of the cerebral cortex?
Thinking, judgment, and problem solving; Voluntary movement; Language & communication; Consciousness & sense of self; Memory; Complex emotions; Perception; Complex mind-body interactions.
What is the structure of the cerebral cortex?
A thin sheet of neurons and glia covering the cerebrum’s exterior surface
varying in thickness from 1.5 to 5 mm
containing approximately 30-100 billion neurons.
What are the types of folds in the cerebral cortex?
Sulcus = fold
Fissure = deep fold
Gyrus = elevation between folds.
What are the three types of cortex within the cytoarchitecture?
Paleocortex (olfactory system), Archicortex (limbic system), Neocortex (90% of cortex).
How are cortical neurons arranged in the cerebral cortex?
Cell bodies of cortical neurons are arranged in layers parallel to the surface of the brain, with 6 layers in neocortex and 3-4 layers in other cortices.
What are the predominant cell types in the cerebral cortex?
Pyramidal cells, Stellate (granule) cells, Fusiform cells.
What are pyramidal cells?
large pyramidal cells are called betz cells
What are Stellate (granule) cells?
serve as interneurons within the cortex
What are fusiform cells?
spindle shaped output cells in deepest layers
What is the granular type of neocortex?
Granular layers are well developed, with prominent layers 2 and 4, found in the primary somatosensory cortex.
What is the agranular type of neocortex?
Layers 3 and 5 are well developed; pyramidal cells are very large, found in the primary motor cortex and other areas of the frontal lobe.
What is Brodmann’s number?
A system where each area of cortex with a common cytoarchitecture is given a number, suggesting that areas that look different perform different functions.
What is area 4 in Brodmann’s map?
The primary motor cortex, also called the precentral gyrus.
What is area 3,1,2 in Brodmann’s map?
The primary somatosensory cortex, also called the postcentral gyrus.
What is area 6 in Brodmann’s map?
The motor planning area.
What is area 17 in Brodmann’s map?
The primary visual cortex.
What are the functional regions of the cerebral cortex?
Sensory Areas (primary and secondary sensory cortex)
Motor Areas (primary motor cortex and motor planning areas)
Association Cortex (areas not classified as sensory or motor).
What is the sensory homunculus?
A distorted representation of the human body based on the density of sensory receptors in each body part.
What are Secondary Sensory Areas?
analyze one type of sensory input from the thalamus and/or primary sensory cortex
ex. secondary visual, secondary auditory, and secondary somatosensory
What is stereognosis?
The ability to recognize objects by touch, testing the function of the secondary somatosensory cortex.
What is astereognosis?
Lack of object recognition despite an intact sensory system.
What is agnosia?
A general term for the inability to recognize objects using a specific sense, despite intact discriminative ability.
- Agnosias commonly result from lack of communication between areas of cerebral cortex
- Specific types of agnosias include: visual agnosias , astereognosis, auditory agnosias
What is visual agnosia?
Inability to visually recognize objects despite intact vision, which may be specific (e.g., prosopagnosia for faces).
What is apraxia?
Inability to perform a movement or sequence of movements despite intact sensation and understanding of the task.
