1. Building up Analgesia in Humans via the Endogenous μ-Opioid System by Combining Placebo and Active tDCS: A Preliminary Report DosSantos, Marcos F.; Martikainen, Ilkka K.; Nascimento, Thiago D.; Love, Tiffany M.; DeBoer, Misty D.; Schambra, Heidi Maren; Bikson, Marom; Zubieta, Jon-Kar; DaSilva, Alexandre F. 2014 Articles Prefrontal cortexNeural transmissionAnalgesicsBiochemistry