(A) Scheme showing the different LED-mediated irradiation points within the pain neuraxis (i.e. hind paw and thalamus) and pain triggering (i.e. hind paw formalin administration and chronic constriction injury -CCI- of the sciatic nerve). VPM, ventral posteromedial nucleus. (B) Chronic constriction injury (CCI) of the sciatic nerve causing mechanical allodynia. Mechanical thresholds were measured in 21 days post-surgery CCI mice. Thus, animals were intraperitoneally injected with vehicle (Veh, saline), raseglurant (Ras, 10 mg/kg) or JF-NP-026 (JF, 10 mg/kg) 20 min before the thalamus was irradiated at 405 nm (or dark) for 5 min. Subsequently, the mechanical thresholds were assessed before and after light irradiation. Values are means ± S.E.M. of 7–9 mice per group. **p<0.05, Student t test, JF-NP-26 dark vs. JF-NP-26 irradiated and raseglurant dark vs. Veh dark.