ʻInhibitoryʼ Test Paradigms: Study Design.

△ Objectives related to the specific perspectives of the review.¤ HNCS in man, DNIC in animals (the authors’ terminology [21]).BI = first-degree burn injury; BOLD = blood-oxygen-level dependent contrast imaging; BTS = brief thermal sensitization; CB = counterbalanced; CPTT = cold pressor test; DB = double-blind; CYP2D6 = cytochrome P450 2D6 enzyme; CPM = conditioned pain modulation; DLPFC/PMC = right dorsolateral–prefrontal cortex premotor cortex (see LDPFC); DNIC = diffuse noxious inhibitory controls; EP = [somatosensory] evoked potentials; EPT = electrical pain threshold; EPIS = endogenous pain inhibitory system; fMRI = functional magnetic resonance imaging; HNCS = heterotopic noxious conditioning stimulations; IDES = intradermal electrical stimulation (rectangular, 0.5 ms duration, 2 Hz, high density); LDPFC = left dorsolateral prefrontal cortex; M1 = primary motor cortex; NFR = nociceptive flexion reflex; NRR = not relevant for the review; NTx = naltrexone; Nx = naloxone; OIH = opioid-induced hyperalgesia; R = randomized; PC = placebo-controlled; SB = single-blind; SBP = systolic blood pressure; SC = sham-controlled; SHA = secondary hyperalgesia area; SOWS = subjective opioid withdrawal scale; SSEP = EP; TCI = target-controlled infusion; TDES = transdermal electrical stimulation (low density); TENS = transcutaneous electrical nerve stimulation; X = cross-over (side to side); 2-D/3-D = two-/two-dose; 2-WX /3-WX/4-WC = two-/three-/four-way cross-over; 3-SX/4-SX/5-SX/6-SX = three-/four-/five-/six-session cross-over study; 8-S = eight session study; 2-PG/3-PG/4-PG/6-PG = two/three/four/six parallel-groups; 2x2-WX = 2 parallel groups each with a 2 way-cross over design.ʻInhibitoryʼ Test Paradigms: Study Design.