Some coma patients may be conscious. New research could identify them.

Some brain injury patients may appear to be in a coma, but they are not. They are processing at least some of what is happening around them but cannot physically respond.

Without a physical response, a physician might assume that a patient hasn’t understood, said Sudhin Shah, a neuroscientist at Weill Cornell Medicine in New York City. And, she said, referring to the patient, “Unfortunately, it could be that you were processing, you were understanding, you were wanting to talk to me. You just can’t.”