The neuroscience of placebo effects A large proportion of the benefit that a person gets from taking a real drug or receiving a treatment to alleviate pain is due to an individual’s mindset, not to the drug itself. Understanding the neural mechanisms driving this placebo effect has been a longstanding question. A meta-analysis published in Nature Communications finds that placebo treatments to reduce pain, known as placebo analgesia, reduce pain-related activity in multiple areas of the brain. Previous studies of this kind have relied on small-scale studies, so until now, researchers did not know if the neural mechanisms underlying placebo effects observed to date would hold up across larger samples. This study represents the first large-scale mega-analysis, which looks at individual participants’ whole brain images. It enabled researchers to look at parts of the brain that they did not have sufficient resolution to look at in the past. The analysis was comprised of 20 neuroimaging studies with 600 healthy participants. The results provide new insight on the size, localization, significance and heterogeneity of placebo effects on pain-related brain activity.