Chapter 12- The central nervous system Flashcards
What are the 4 regions of the brain in adults?
- Cerebral hemispheres
- Diencephalon
- Brain stem
- Cerebellum
Gray matter
Short, nonmyelinated neurons and neuron cell bodies. Contains dendrites, cell bodies, and axon terminals. Gray matter is peripheral in the brain
Gray matter function
Function- all synapses are found in gray matter- motor controls, sensory perception, decision making, etc
White matter
Myelinated axons, mostly in fiber tracts (bundles of axons that save space). White matter is central in the brain.
White matter function
Function- passes “messages” between different areas of gray matter
Cortex
The outer layer of gray matter in the brain
How are gray and white matter distributed in the brain stem?
Scattered gray matter is found within white matter
How are gray and white matter distributed in the spinal cord?
Gray matter surrounds a central cavity with white matter external to it- similar to the brain
Ventricles
Hollow chambers found in the brain that are filled with cerebrospinal fluid (CSF) and lined with ependymal cells (produce, secrete, and circulate CSF). CSF circulates between all ventricles freely- all ventricles don’t produce their own personal CSF
Where are the ventricles located?
- 2 lateral ventricles- one in each cerebral hemisphere
- Third ventricle- found in diencephalon
- Fourth ventricle- found in the hindbrain, continuous with the central canal of the spinal cord.
All 4 chambers are continuous with one another
Cerebral aqueduct
How the fourth ventricle connects to the third ventricle
Cerebral hemispheres
Form the most superior portion of the brain, make up most of the brain by mass
Regions of the cerebral hemispheres (3)
- Gray matter (cerebral cortex)
- White matter
- Basal nuclei
Gyri
Characteristic ridges of the cerebral hemispheres
Sulci
Characteristic shallow grooves of the cerebral cortex, divides the cerebral hemispheres into lobes. Almost all lobes are named after the bones they are found under (except for the insula).
Longitudinal fissure
Fissure that separates the left and right hemispheres
Transverse cerebral fissure
Fissure that separates the cerebral hemisphere from the cerebellum
Central sulcus
Separates the frontal lobe and the parietal lobe
Parieto-occipital sulcus
Separates the occipital lobe from the parietal lobe
Lateral sulcus
Separates the temporal lobe from the frontal and parietal lobes
Where is the insular lobe located in the brain?
Insula are buried in the lateral sulcus, must cut into the brain to find the insular lobe
Cerebral cortex/gray matter functions (6)
The portion of the brain where the conscious mind is found
Function- provides self awareness, sensation, communication, memory, understanding/learning, initiation of voluntary movement
Functional areas of the cerebral cortex (3)
- Motor areas- control voluntary movement
- Sensory areas- conscious awareness of sensations
- Association areas- integrate diverse information
Contralateral
Describes the cerebral hemispheres- the right hemisphere is concerned with the sensory and motor functions of the left side of the body and vice versa (opposite side of the body from the brain structure).