After suffering a brain hemorrhage, 7-year-old Charlotte Neve slipped into a coma. The British girl was unconscious for several days and doctors feared she wouldn’t recover. Her mother, Leila Neve, was at her bedside when Adele’s “Rolling in the Deep” started playing on the radio. Leila and Charlotte often sang the song together and Leila began singing along.

Then something remarkable happened: Charlotte smiled. Within two days, she could speak and get out of bed. Why does music seem to help "awaken" some people from their comas?

“It was a salient stimulus, something that she is familiar with, like [her] name,” says Dr. Emery Neal Brown, professor of anesthesia at Mass General Hospital and Harvard Medical School and professor of computational neuroscience at MIT.

Brown suspects Charlotte recovered some brain functioning prior to hearing the Adele song, but it was imperceptible. When she heard the song, she smiled and eventually woke because it held meaning for her (that's the salient stimulus part).  

“Maybe people have function recovered and we don’t know how to communicate with them,” he says, explaining a salient stimulus varies by person.

“Whenever memories have an emotional context to them, they tend to hold much more power in the brain and tend to be processed differently,” says Dr. Javier Provencio, director of the Neurological Critical Care Unit at Cleveland Clinic.

Robin Gibb of the Bee Gees woke from his coma when his family played music for him — music for a professional musician who sang with his brothers would have deep meaningful connections in the brain, sparking a reaction. But for someone who plays tennis or rides horses, a song might not encourage a response. 

But sometimes, music causes a reaction because the brain processes songs differently than spoken language. In these cases, the region of the brain responsible for song might be working better while the language lags behind.

“We clearly process music and tonal things differently than language. There are patients [who had strokes] who cannot talk but can still sing,” says Provencio.

The left cerebral hemisphere controls language, while the right processes song and music. Patients who have damage in the left might respond better to song.

“They lose the ability to talk and understand. Music therapy is really useful because it is used in the non-dominate hemisphere,” says Dr. James Bernat, professor of neurology and medicine at Geisel School of Medicine at Dartmouth and a member of the American Academy of Neurology.

Music therapists such as Lee Anna Rasar at the University of Wisconsin Eau Claire often use music to try to evoke responses from comatose patients. She notes that songs are most effective “if the music is something they knew before that already had meaning.”

All the physicians agree that doctors still have limited understanding of whether someone will recover from a coma, but if Charlotte wasn’t already healing, she wouldn’t have smiled at the song.

“Even in a coma, it’s quite common that these people improve spontaneously,” says Bernat. “They wake up and start responding. It isn’t outside the range of what is expected that there would be improvement over time.”

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