"Where does it hurt?" the doctor asks the patient with chronic pain. The patient indicates the place, and the doctor pokes the spot with a blunted pin. The doctor then asks for an "ouch" rating on a scale of 1-10 and writes it down.

Dr. Mathew Lee of NYU's Rusk Institute of Rehabilitation Medicine hopes to skip this unpleasant task by simply having patients pose for his "pain camera."

At heart, Lee's equipment is a thermograph -- an extremely sensitive infrared camera that sees in heat waves. Similar to the night-vision scopes sold in spy stores, Lee's thermograph is fine-tuned to extremely subtle distinctions of temperature. When pointed at a person, you can easily see that the nose is typically colder than the face, while the lips tend to be slightly warmer.

These normally undetectable differences in skin temperature are a vital clue to blood flow under the surface. Patients with chronic pain will typically experience more blood flow to the sensitive area -- making it literally stand out like a sore thumb. By comparing a person's left side to their right, other conditions also can be spotted that would have gone unnoticed by doctor and patient.

With a compiled "default" body temperature map, the doctor can track changes in the patient's condition. But it's easy to forget all the science and medicine involved when contemplating these eerily anonymous "heat people" photos. And when a new patient of Lee's turned out to be a world-renowned pioneer of video art, Lee had another idea.

The patient, Nam June Paik (pictured), arrived for chronic pain treatment but remained to help Lee turn science into art. In this thermograph entitled "The Artist," Paik's right hand is dramatically warmer than his left due to the chronic pain a stroke left him on his right side. Lee and Paik's series of thermographs entitled "The Philosophy of Pain" were recently exhibited at the John Goodman Gallery in New York City.

-- Robert Myers