What are the 3 general functions of the spinal cord?
- Sensory input and motor output for the neck, trunk, limbs and tail
- Reflexive control of patterned movement and adjustment of glandular activity
- Transmission of information to and from teh brain
The spinal cord recieves sensory information from peripheral nerves via
Motor commands are sent to the skeletal and smooth muscle via
What are the function of interneurons?
receive and integrate afferent information to adjust local muscle and glandular activity to adapt to sensory environment
Ascending fiber pathways carry what kind of information?
sensory information to the brain
Descending fiber pathways carry what kind of information?
Commands from teh brain to the body to regulate posture, voluntary movement and visceral aspects of behavior
a spinal nerve, when it leaves through the intervertebral foramen splits into four branches:
- communicating branches (GVE and GVA)
Grey matter of the spinal cord contains
cells bodies of neurons
What are the four regions of grey matter?
dorsal horn, intermediate zone, ventral horn and lateral horn
The Dorsal horn of grey matter is responsible for?
receiving, processing and relaying afferent information from teh dorsal root fibers
The intermediate zone of grey matter is responsible for?
interneurons, used in the production of reflexes, such as antigravity, support, balance, and voluntary movement
The ventral horn of grey matter is responsible for?
contains motor neurons that send their axons through the ventral root to innervate muscle fibers
The lateral horn of grey matter is responsible for?
contains cell bodies of preganglionic sympathetic neurons
only located at segments T1-L3/4
White matter of the spinal cord contains
myelinated and unmyelinated axons
Upper motor neurons are located where?
UMN are descending neurons originating form the cerberal motor cortex or various nuclei of the brainstem and synapse into interneurons to affect LMNs located in the spinal cord
Lower motor neurons are located where?
LMN originate in the brainstem or spinal cord that synapse onto skeletal muscle fibers (femoral n)
What is the cauda equina?
It is a collection of spinal nerves that stretch caudally