| Term 
 | Definition 
 
        | the conversion of energy from a noxious thermal, mechanical, or chemical stimulus into a nerve impulse via nociceptors |  | 
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        | Term 
 
        | mediators that activate nociceptors |  | Definition 
 
        | prostaglandins cytokines
 histamine
 serotonin
 substance P
 |  | 
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        | Term 
 | Definition 
 
        | transduction, transmission, modulation, and perception |  | 
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        | Term 
 | Definition 
 
        | impulses travel via axons of primary afferent neurons to the dorsal horn of the spinal cord |  | 
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        | Term 
 | Definition 
 
        | nociceptive information is interpreted in the cerebral cortex in terms of location, intensity, and quality |  | 
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        | Term 
 | Definition 
 
        | the attenuation of dorsal horn transmission by descending inhibitory input from the brain (supraspinal, spinal, and peripheral) |  | 
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        | Term 
 | Definition 
 
        | pain from internal organs |  | 
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        | Term 
 | Definition 
 
        | pain from skin, bone, muscle, tissue |  | 
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        | Term 
 | Definition 
 
        | caused by aberrant signal processing in PNS or CNS - injury to nerves caused by metabolic disease, infection, tumor, toxin, etc; often unresponsive to NSAIDS or opiates |  | 
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