摘要：Clinical trials of post-traumatic stress disorder (PTSD)show a high rate of placebo response, ranging from 19%to 62% (Ipser Kelmendi et al., 2016; Sher,2004). Despite these placebo responses across a numberof clinical trials, nothing is known about their underlyingmechanisms. In fact, the clinical trial setting does notallow us to differentiate between placebo effects due topsychological factors such as patients’ expectations andother phenomena such as spontaneous remission andregression to the mean. The recent explosion of placeboresearch and the shift in conceptualization of the placeboeffect in several medical conditions, such as pain andmotor disorders, makes us understand that their psychological and neurobiological underpinnings can be investigated in some detail. Indeed, what we have learned overthe past few years is that different brain mechanisms areat work during the placebo response (Benedetti,Amanzio, Rosato, Benedetti,Carlino, Wager & Atlas, 2015).
