Pain (3) Flashcards
Anethesia
loss of sensation
Hyper-esthesia
generalized increased sensation
Ex: allodynia = pain with light touch
Dysesthesia
Abnormal sensation
Ex: causalgia = burning pain
paraesthesia
tingling
hypoesthesia
generalized decreased sensation
“Where Pathway” is associated with which tract?
spinothalamic pathway
Fxn of the “what are you going to do about it” pathway?
coveys poorly localized, aching, second, slow, protopathic pain to widespread areas of the cortex
What physiological response is associated with “what are you going to do about it” pathway?
Affects arousal, autonomic and limbic systems.
Both pathways: 1st order neuron synapses in the _________.
dorsal horn
Effects of nociception?
Overall increase in CNS arousal
Increased sympathetic tone
Increased alpha motor neuron excitability
__________ pain could be soft tissue damage, muscle, chemo irritant etc
Peripheral
________ pain arises when nervous tissue dsyfunctions.
Neuropathic
With ________ pain peripheral cause of the pain may or may not any longer exist.
chronic
What can lower threshold of receptors contributing to chronic pain?
Chronic stimulation
Neuronal damage in which case mechanosensitive and chemosensitive sodium channels that are inserted in demyelinated portions of the membrane is called:
extopic foci
Pain from nerve injury or synaptic reorganization is classified as
Neuropathic Chronic Pain
“Cross Talk” between neurons in areas of demyelinization is known as
ephatic transmission
Action potentials in touch neuron can cause AP’s in pain neuron.
Intense signaling from the periphery can induce the increased sensitivity due to upregulation of transmitters and receptors in a process called
central sensitization
maladaptive response to chronic pain
Touch may be perceived as pain due to collaterals connecting with pain transmission cells in what process?
structural reorganization
__________ influence from higher centers to spinal cord are reduced.
anti-nociceptive
__________ influence from higher centers to spinal cord are increased.
pro-nociception
__________ is a situation where the spinal cord may get “confused” as the to actual source of the pain and it can be “felt” in an area that is not the source of the painful stimulus
referred pain
Which axons both converge on the same pain transmission neuron in the spinal cord with referred pain?
Cutaneous and visceral afferents
What molecule is involved in the upregulation neurotransmitters involved in pain?
BH4
What percent of pain thresholds are inherited?
50%
Touch receptors synapse with enkephalin producing interneurons in dorsal horn in which theory? What do interneurons do?
counter irritant theory
interneurons inhibit pain transmission cells!
What system is described below?
Collaterals from the ascending pain pathways activate descending projections from brainstem can inhibit pain transmission neuron through interneurons.
Descending Anti-Nociceptive Systems
Descending Anti-Nociceptive Systems use which endogenous opiate neurotransmitters?
enkephalins/endorphins
What morphine antagonist reverses analgesias related to enkephalins/endorphins?
Naloxone
Supersensitizing pain (ie: ankle sprain) is related to what system?
peripheral pro-nociception mechanisms
Chronic stress and depression lead to what central mechanisms?
increased pronociception
