by Jonah Lehrer

What makes for an effective surgery? At first glance, the answer seems simple: surgery is about brute anatomy. It’s a matter of setting shattered bones, excising malignant tumors and clearing the pipes of the heart. In other words, a good operation fixes the body, that fleshy machine.

But is it really so simple? A new study demonstrates that even straightforward surgeries, such as repairing a “slipped” spinal disk, contain a large mental component that has nothing to do with the back. Here’s Vaughan Bell, over at Mind Hacks:

The researchers, a surgical team from St George's Hospital in London, were aware that anxiety and depression had a major influence on recovery after surgery for a type of spinal disc tear, commonly but inaccurately known as a 'slipped disc'.

They decided to try a simple measure to help patients feel less anxious and bolster their belief that a good job had been done: the surgeons presented randomly selected patients with the removed fragments from their back.

This simple technique had a remarkable effect. Patients given a 'souvenir' of their operation reported greater improvement in sciatic nerve pain, lower back pain, less pins and needles sensations, less leg weakness and a reduced use of pain killers.

The larger point is that our expectations have a profound impact on what we actually experience. If we believe that the surgery went well - and can visualize the shards of removed bone - then we’ll have an easier recovery. For too long, modern medicine has subscribed to a Cartesian duality, in which doctors treat the body and ignore the mind. (Perhaps this is because, for the first 2000 years, Western medicine consisted solely of the placebo effect. If that mercury tonic worked, it’s because you believed it worked.) Research like this demonstrates that we ignore the beliefs of the patient at our own peril.

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