structural:summarization
Detection of noxious stimuli

Nociceptive threshold testing deliberately applies a noxious stimulus to a human or animal subject to study pain. In animals, the technique is often used to study the efficacy of analgesic drugs and to establish dosing levels and period of effect. After establishing a baseline, the drug under test is given and the elevation in threshold recorded at specified times. When the drug wears off, the threshold should return to the baseline (pretreatment) value. In some conditions, excitation of pain fibers becomes greater as the pain stimulus continues, leading to a condition called hyperalgesia.