Effects of an afforestation activity on thermal and mechanical pain mechanisms: A clinical trial

Abstract

Sensory stimulation has shown the capacity to modulate pain mechanisms. Yet, the optimal methods of sensory stimulation remain uncertain. Afforestation activities stand out as a potential stimulation method, as they allow individuals to interact with multisensory stimuli produced in green environments. Exposure to natural multisensory stimuli has been shown to induce neurobiological activations in pain-related brain areas in healthy populations. However, the possible impact of the natural multisensory stimuli on the pain mechanisms themselves is yet to be explored. This study aimed to investigate the potential effects of sensory stimulation experienced during participation in an afforestation program on thermal and mechanical pain mechanisms. A singlegroup, pretest-posttest clinical trial was used. Forty-seven healthy adults performed an afforestation activity for 90 minutes. Measurements included cold pain detection and tolerance thresholds via the Cold Pressor Test, windup and mechanical pain sensitivity through a pinprick stimulator, and pressure pain detection and tolerance thresholds utilizing pressure algometry. For both thermal and mechanical pain thresholds, pain intensity was assessed using the 101-point Numeric Rating Scale. The results showed significant reductions in the cold pain intensity at the moment of detection (p = .046), mechanical pain sensitivity (p ≤ .014), and increases in the thresholds of pressure pain detection (p = .005) and tolerance (p ≤ .046). Therefore, the interaction with natural multisensory stimuli could be a possible therapeutic strategy to positively modulate mechanical pain sensitivity and pressure pain thresholds.