Week 2.2: Histology of the Cerebral Cortex Flashcards
What two types of cells make up the cellular structure of the cerebral hemispheres?
Neurons (excitable cells) and glial (supporting) cells.
What are the most numerous neurons of the neocortex?
Pyramidal cells.
What is the name of the giant pyramidal cells found in the motor cortex?
Betz cells.
What do the axons of pyramidal neurons form?
The projection and association fibers of the cortex.
What is the function of stellate neurons?
They act as interneurons.
What is the outer layer of the cerebral hemisphere called?
The cerebral cortex.
How many layers does the neocortex have?
Six horizontal layers.
How many layers does the allocortex (archicortex), such as the hippocampus, have?
Three cellular layers.
What is the molecular layer (Layer I) composed of?
Afferent fibers from within the cortex or other brain regions.
What is the external granular layer (Layer II) composed of?
A dense layer of small cells.
What type of cells are found in the external pyramidal layer (Layer III)?
Pyramidal cells, often arranged in rows.
What is characteristic of the internal granular layer (Layer IV)?
It is a thin layer with small granular cells similar to Layer II.
What type of neurons are found in the internal pyramidal layer (Layer V)?
Large pyramidal cells that project to the brainstem and spinal cord.
What is the fusiform (multiform) layer (Layer VI)?
The deepest layer of the neocortex, containing a mix of cell types.
