When a brain-damaged person seems unresponsive, the uncertainty is excruciating. Is the person in a vegetative state, awake but not conscious, or are they minimally conscious, still retaining some shreds of awareness? Scientists can now distinguish between people in vegetative and minimally conscious states by measuring brain waves, a Belgian research team announced at the Society for Neuroscience conference last week, which could lead to a more clear-cut, objective way to make the diagnosis.
Doctors long believed that patients who remained in a coma weeks or more after a brain injury would never regain consciousness. But recent research has shown that consciousness isn’t a binary, awake-or-not state; it’s a spectrum. While some brain injury patients are in a vegetative state, without any conscious awareness, others are in what’s called a minimally conscious state, still partially aware of—and at times even able to respond to—their surroundings. From the outside, it can be difficult to tell the two apart, though new methods, such as EEGs that pick up on subtle differences in brain waves, are starting to help clinicians gauge a patient’s level of consciousness.
From these hinterlands of consciousness comes another astounding—and mysterious—discovery: Ambien, the prescription sleep medication, and zolpidem, the drug’s generic form, can help some minimally conscious patients wake up. Jeneen Interlandi delves deep into this seemingly paradoxical treatment in the New York Times magazine:
What’s the News: A non-invasive test that measures brain waves could help doctors better diagnose whether a patient is truly in a vegetative state, according to a preliminary study published today in Science. What’s more, the results suggest that a particular pathway of communication in the brain is disrupted in vegetative patients but not patients with somewhat less severe brain damage—which could not only improve diagnosis, but help researchers better understand these tragic conditions.