Belgian doctors discovered that some comatose patients develop the same "pain matrix" in the brain as healthy individuals do when subjected to pain stimuli. This gives further justification to medics administering painkillers to patients previously believed to have had no functioning pain receptors. Caregivers have been employing such measures in hospitals worldwide for years, but only in the treatment of those suffering from minimally conscious state (MCS) coma.
 

A coma is a sleep-like state defined by the lack of both reactivity and perceptiveness. People in a coma cannot react to regular stimuli, such as motion, sounds and pain. Orientation and balance are also impossible in this state. Furthermore, patients in comas lose their ability to respond to learned skills, such as spoken language, individual gestures and other communication skills. Specialists say that people exit their comatose state when they are fully awake and when they have both their reactivity and perceptiveness back.
 

The discovery, published in the Lancet Neurology, was made by a team of researchers at the Coma Science Group of the Cyclotron Research Center at the University of Liege, led by Steven Laureys. He said "These findings might be objective evidence of a potential pain perception capacity in patients with MCS, which supports the idea that these patients need painkilling treatment." Unfortunately, the brains of patients in persistent vegetative state (PVS) coma were very little affected by the pain stimuli, which led scientists to further conclude that they were indeed "brain-dead." According to Laureys, the presence of the pain matrix is observed even in those under severe anesthesia. Not seeing it in PVS patients only shows they have little chance of recovery.
 

After publishing the study, the team turned its attention to the sedative dosage patients in MCS should receive. This is very important, because a high dose could sedate them and inhibit signs of recovery or consciousness. In addition, doctors started another study, meant to analyze the brains of people undergoing surgery, in order to determine exactly how the pain matrix is formed.