The researchers then told them that intravenous saline drips might be painkillers and asked them to rate the intensity of their discomfort on a scale of 0 to 100 every 15 seconds.

• 接著研究人员告诉志愿者，在静脉内注射盐水点滴，可能有止痛的功效，然后要求志愿者每15秒钟，评估自己不舒服的强烈程度，以100分为满分。