week 3 Flashcards
Differntiate between alpha delta fibres and c fibres
There are two types of nocioceptive neuorns - both associated with different types of pain transmissions.
AD fibres myleniated are for sharp, well-localised pain, where as unmyelinated c fibres inputs are linked to sensations of dull, aching pain that is difficult to pinpoint.
differentiate between nociception and pain
Nociception is the signal that is sent to the brain in recognition of an injuiry
Nociception refers to neural encoding of impending or actual tissue damage (noxious stimulation), pain refers to to the subjective experience of actual or impending harm
describe hyperalgesia and allodynia and the role they thought to play in normal nociceptive signalling
Hyperalgesia is when a stimulus that would cause x amount of pain would cause more then. if you hit your ankle against a table, it would hurt x amount, but would hurt more if the ankle was sprained.
Allodynia is something that shouldn’t cause pain that does. - e.g., standing on an ankle (but because it is sprained it hurts more).
DIfferentiate between productive and non-productive pain
productive pain has been described as a warning of an injuiry - serves as a guide to treatment
non-productive pain pain by definition serves no purpose either as a warning or diagnostic tool
Explain why pain is described as subjective sensation
pain is the perception of the brain from the nociceptive information delivered from the neural pathways
In an extreme example, someone who was born without c fibres usually die young as a result of not noticing the pain from injuiries and infections
describe how neuropathic pain differs from chronic pain
definition of neurpathic pain = caused/initiated by a primary lesion or dysfunction in the somatosensory system (CNS) whereas chronic pain is more prolonged and lasts several months/years - often because of a health condition.
chronic pain can be any part of the pain pathway - transduction,
neuropathic pain only affects the neuorns - trandusction or transmission
describe the process by which the CNS uses the endognous analgesic pathway to modulate pain
The ascending pathway is what is used to send the signal to the brain so it can percieve pain.
When this pain perception begins, there is a descending pathway that releases endogenous opioids to decrease/stop the signal of the ascending pathway.
This is done by hyperpolarisation and decreasing neurotransmitter release.
Hyperpolarisation occurs as the descending pathway promotes K to exit the cell, making the cell more negative and requiring a hire stimulus for an action potential.
Neurotransmitters releasing is decreased by decreasing calcium conductance.
outline the role of opiate abtagonist such as naloxone on pain receptors and their role in clinicala practice
Naloxone is a competitive antagonist. Not only does it bind to opioid receptors and prohibit other opioids from binding, but because it has a higher affinity than opioids, they can kick of opioids from opioid receptors and negate them from taking affect.
clinical practice: opioid overdose
