| Abstract: | Introduction: Although acupuncture reduces pain and is important in its effect, the role of coping strategy on acupuncture modulation of pain and sensory thresholds, and the association between acupuncture sensation and these modulatory effects, is currently unknown.Methods: Electroacupuncture(EA) was applied at acupoints ST36 and GB39 in 61 healthy adults.Two coping conditions were experimentally designed to form an active coping strategy group(AC group), who thought they could control EA stimulation intensity, and a passive coping strategy group(PC group), who did not think they had such control.However, the EA intensity was not changed.Quantitative sensory testing was performed before and after EA, and vibration(VDT), mechanical(MDT),warm(WDT), and cold(CDT) detection thresholds, and pressure(PPT), mechanical(MPT), heat(HPT) and cold(CPT) pain thresholds were measured.Autonomic measures, skin conductance response(SCR), were also acquired to quantify physiological response to EA under different coping conditions.Results: The AC group showed greater SCR to EA than the PC.Acupuncture sensation did not differ between the AC and PC groups.Increased pain/sensory threshold and acupuncture sensation were positively correlated in the AC group(VDT change vs.MI: r=0.58; CDT change vs.tingling: r=0.53; CPT change vs.tingling: r=0.55; CPT change vs.dull: r=0.55), and were negatively correlated in the PC group(CDT change vs.intensity: r=-0.52; WDT change vs.fullness: r=-0.57).Additionally, subjects in the AC group demonstrated reduced PPT following EA.Conclusion: Active coping strategy increased pain and sensory detection threshold when acupuncture sensation was high, while passive coping strategy produced an opposite association.Theassociation of descending cortical(psychological coping strategies) and ascending sensory afference(acupuncture sensation) might affect periaqueductal grey to modulate pain and sensory processing.Clinically, our findings suggest that acupuncture analgesia can be maximized by matching physical stimulation intensity with the psychological coping strategy inherent to different naturalistic subject-specific acupuncture contexts. |
