Good doctors really do feel their patients' pain.

A study, published today (Jan. 29) in the journal Molecular Psychiatry, shows that when doctors see their patients experiencing pain, the pain centers in the physicians' own brains light up. And when the doctors give treatment to relieve pain, it activates the physicians' reward centers.

"Doctors feel rewarded when they are responsible for someone's relief," said study author Karin Jensen, a researcher at Massachusetts General Hospital. "The better they are at taking the perspective of the patient, the more reward and subjective value they will report."

Mysterious bond

Jensen's past work has shown that patients respond better to placebo or sham treatments if they feel strongly bonded to their doctors. But it wasn't clear how the doctors' feelings mediated that effect.

"We wanted to see what happens in the doctors' brain[s] as they are treating a patient," Jensen told LiveScience. "We were turning the tables on the doctor-patient relationship."

To explore this question, Jensen had 18 doctors meet with one of two 25-year old "patients" for a general checkup, during which the women said that they suffered from menstrual cramps and were very sensitive to pain. Though the doctors believed the patients were real, the women were in fact following a script.

Separately, researchers tested the doctors on their ability to take the perspective of their patients.

Afterwards, Jensen hooked the doctors to a functional magnetic resonance imaging machine, which measures blood flow as an indicator of brain activity, as the physicians viewed their "patients" experiencing pain caused by heat.

The doctors were then instructed either to use an electronic device that they believed would relieve the patients' pain, or to withhold the pain relief. In response, the patient-actors either grimaced in pain or maintained a neutral expression to suggest their pain had subsided.

When the patients experienced pain, the pain centers in the doctors' brains lit up. When the physicians "relieved" their patients' pain, regions in the doctors' brains responsible for the placebo response and reward centers were activated.

The more doctors could relate to the patient's perspective, the more the physicians' reward centers lit up when they were able to relieve pain, Jensen said.

The findings may shed light on how the doctor-patient relationship affects patients' experience of care, Jensen said. The doctor's response may also add another layer to the complex factors that mediate the placebo response, she said.

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