W7 - Perpheral Nervous System & Pain Flashcards
(18 cards)
What are the functions of the peripheral nervous system
Communication system of the body
Sending info from different areas of the body back to the brain (afferent sensory) as well as carrying info front, the brain to the rest of the body (efferent motor)
How many cranial nerves are there
12 but only 11 are in the PNS
Which cranial nerve is part of the CNS and what does it do
2nd one & it controls vision
How many spinal nerves are there
31 pairs
They attach to the spine at each segment bone (vertebrae)
What is a dermatome
Strip of skin inervated by a single strip of nerve
What is a myotome
Group of muscles inervated by a group of spinal nerves
2 divisions of the PNS
Somatic (voluntary actions) & autonomic (regulates the internal environment & involuntary control of automatic processes)
What is the autonomic system divided into
Sympathetic (fight or flight) & parasympathetic (rest & digest)
Define pain
An unpleasant sensory and emotional experience associated with actual or potential tissue damage or described in terms of such damage
What senses does pain come from
Somatory sensors
What fibres are small/medium diameter and myelinated and produce fast pain
A delta fibres (nociceptors)
What fibres are small in diameter and are non-myelinated
C fibres (nociceptors)
What fibres are large in diameter and myelinated but are mechanical stimuli such as heat or cold
A beta fibres (mechanoreceptors)
What route does a pain signal go along in the CNS
Stimulus
Nociceptors
Afferent nerve fibre
Dorsal horn
Glutamate substance P
Secondary neuron
Thalamus (sorting office)
Limbic system (emotional links)
Somatosensory cortex (sensation experienced as pain)
Is the gate open or closed if A beta fibres are activated
Closed
Is the gate open or closed if both A delta and C fibres are activated
Open
Does state of mind open or close the gate
Open
Do endorphins open or close the pain gate
Close
