OK, it’s not news that placebos work. But it is interesting that they work even when patients are told that they being given a placebo. And it’s even more interesting to note that doctors can tell, by looking at a patient’s brain anatomy and psychological profile, if the placebo is likely to work for that patient. A Northwestern University news release reports that researchers at the school worked with 60 chronic back pain patients, who were randomized into two arms of the study. In one arm, subjects didn’t know if they got the drug or the placebo. Researchers didn’t study the people who got the real drug. The other study arm included people who came to the clinic but didn’t get a placebo or drug. They were the control group. The researchers found that those whose pain decreased as a result of the sugar pill had a similar brain anatomy and psychological traits: the right side of their emotional brain was larger than the left, and they had a larger cortical sensory area than people who were not responsive to the placebo; the chronic pain placebo responders also were emotionally self-aware, sensitive to painful situations and mindful of their environment. Why it matters: Because it’s much better–for everything from patients’ health to health care costs–if doctors can treat patients with non-active drugs.