The post examines research suggesting placebos are largely ineffective, explores exceptions, and proposes explanations for observed placebo effects based on brain function and study design. Longer summary

This post discusses the placebo effect, focusing on Hróbjartsson and Gøtzsche's research which found that placebos have little benefit over no treatment in most conditions. The author explores the reasons behind this, suggesting that regression to the mean may have been mistaken for placebo effects in earlier studies. The post also discusses exceptions where placebos seem more effective, such as pain and nausea, and offers a potential explanation for the placebo effect based on the brain's predictive processing model. The author concludes by speculating on why depression might not show strong placebo effects in clinical trials despite common assumptions. Shorter summary