DSA - Brain and SC Flashcards
Three divisions of the brain?
Forebrain (cerebral hemispheres and diencephalon)
Cerebellum
Brainstem
~ how many neurons in the nervous system?
100 billion!!!!!
What does the gray matter consist of?
Mainly neuronal cell bodies and dendrites (where the signal starts)
(Outside of brain)
What does white matter consist of?
Areas where there are collection of axons
(Inside of brain)
Myelinated axons (mainly)
Where are the two enlargements of the spinal cord?
Cervical enlargement - upper limb
Lumbosacral enlargement - lower limb
What is the tapering inferior end of the spinal cord called?
Conus medullaris
What’re the groups of axons projecting out of the conus medullaris called?
Cauda equina
What’s the thin strand of pia mater called that anchors the conus medullaris to the coccyx?
Filum terminale
In the posterior horn what is the term for the thing that looks pale because it deals mostly with finely myelinated sensory fibers that carry pain and temperature?
Substantia gelatinosa
What is the name of the white matter located between the substantia gelatinosa and the surface of the cord?
Lissauer’s tract
- contains the fibers with which the substantia gelatinosa deal
What kind of neurons are in the anterior horn?
What do they supply?
large motor neurons that supply skeletal muscle
* lower motor neurons
What horn do the preganglionic sympathetics come from?
Intermediolateral cell column (lateral horn)
The sacral parasympathetics do not have a lateral horn… what do they have instead?
Sacral parasympathetic nucleus
What is Clark’s nucleus?
Collection of large cells on medial surface of the base of posterior horn T1-L2
Name as many “lamina” and what level they come from as you can.
Picture
What is the bundle of axon fibers that receives sensory information from the arms called?
Fasciculus cuneatus
What is the bundle of axon fibers that carries sensory information from the middle thoracic and lower limbs called?
Fasciculus gracilis
In what part of the spinal cord do sensory neurons (coming in the DRG) terminate?
In the spinal gray matter
Describe: gyrus, sulcus, and fissures.
What are the purpose of these structures?
Gyrus is just the shallow ridges of cortical tissues
Sulcus is the groove between gyri
Fissures are deeper sulcus
The purpose is to increase the total cortical area and number of cortical neurons
What are the four prominent sulci that divide each cerebral hemisphere in what 5 lobes?
4 sulci = Central sulcus, lateral sulcus, parietooccipital sulcus, cingulate sulcus
5 lobes = frontal lobe, parietal lobe, occipital lobe, temporal lobe, limbic lobe
What connects the two cerebral hemispheres?
Corpus Callosum
Contains somewhere around 250 million axons
In what lobe is the primary motor complex?
The frontal lobe
What spot in the brain is known to be important in motor aspects of written and spoken language?
Broca’s area (in frontal lobe)
What is the term for the area that occupies much of the frontal lobe, and is involved with executive functions, i.e. personality, decision making, insight, and foresight?
Prefrontal cortex
