Chapter 3.8 - 3.16 Anatomy of the Nervous System Flashcards
There are three axes to the vertebrate nervous system,what are they?
- Anterior (toward nose end) - posterior (toward Tail end)
- Dorsal (toward the surface of the back or top of the head) - Ventral (toward the surface of the chest or the bottom of the head)
- Medial midline of body) - Lateral (away from midline toward lateral surfaces)
See fig 3.14 on page 64 for reference
What is Gray Matter?
- in inner H-shaped core of spinal cord
- Composed largely of cell bodies and unmyelinated interneurons
What is white Matter?
Composed largely of myelinated axons
What are the five divisions of the brain?
- Telencephalon (cerebral hemispheres)
- Diencephalon
- Mesencephalon (midbrain)
- Metencephalon
- Myelencephalon (medulla)
What is the brain stem?
The stem on which the cerebral hemispheres sit
What is the myelencephalon?
Aka Medulla
- most posterior division of the brain
- composed largely of tracts carrying signals btwn rest of brain & body
- has reticular formation
What is the reticular formation?
Complex network or about 100 tiny nuclei that occupies the central core of the brain stream from the posterior boundary of the myelencephalon to the anterior boundary of th midbrain
What is the metencephalon?
-like myelencephalon, houses many ascending and descending tracts and part of the reticular formation
2 divisions:
1. a bulge called the “pons” on the brain stem
2. The cerebellum (little brain)
What is the cerebellum?
In the metencephalon division
- sensorimotor structure
- large convoluted structure on brain stems dorsal surface
- damage also leads to deficits in decision making and using language
What is the mesencephalon?
Has two divisions:
- Tectum (dorsal surface of midbrain)
- Tegmentum (ventral to the tectum)
What are the two pairs of bumps on the Tectum and what is their function?
- Inferior coliculi (posterior pair)
- auditory function - Superior coliculi (anterior pair)
- visual-motor function
What three structures are found in the Tegmentum (division of the mesencephalon)?
- Periaqueductal gray: gray matter around the cerebral aqueduct
- Substantial Nigra: black substance
- Red Nucleus
What is the cerebral aqueduct?
Duct connecting the third and fourth ventricles
-role in mediating the analgesic (pain-reducing) effect of opioid drugs
What is the diencephalon?
- composed of two structures :
1. Thalamus
2. Hypothalamus
What is the thalamus (structure of diencephalon division)
Large two lobed structure that constitutes the top of the brain stem
-joined by the massa intermedia