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To watch Henry—an elderly man who has spent over ten years in a nursing home, barely able to answer yes or no questions—come alive when listening to music from his past is a reminder of the powerful, inspiring, and affecting power of music.

A new documentary, Alive Inside, follows the “awakening” that occurs when people suffering from memory loss and Alzheimer’s are given music they have a strong emotional connection to — often, music they grew up with. In the clip, Henry is barely responsive before one of his caretakers puts headphones on him and starts up one of his favorite tunes. Almost instantly, we see Henry swaying from side to side and singing, his eyes wide open.

“The philosopher Kant once called music the ‘quickening art.’ And Henry is being quickened, he’s being brought to life,” says Dr. Oliver Sacks, a neurologist and author of Musicophilia, who is involved with the documentary.

After his headphones are taken off, Henry answers questions about his favorite music, speaking excitedly and recalling memories. “I’m crazy about music, and you played beautiful music, beautiful sounds,” he says. “Cab Calloway was my number one band—guy I liked,” he remembers, before breaking into a vibrant rendition of “I’ll be Home For Christmas.”

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Alive Inside follows social worker Dan Cohen, executive director of the non-profit Music & Memory, as brings iPods to a nursing home. The transformation in barely responsive, “lost” patients was remarkable; as seen with Henry in the clip above, the music worked like a jolt of electricity for patients, transporting them back in time and even allowing them to speak animatedly after the music was turned off.

Sacks explains, “Music imprints itself on the brain deeper than any other human experience. Music evokes emotion and emotion can bring with it memory.” Furthermore, he says, “music brings back the feeling of life when nothing else can.”

When an interviewer asks Henry, “What does music do to you?” Henry responds without missing a beat.

“It gives me the feeling of love, romance! … The Lord came to me and he made me a holy man, so he gave me these sounds.”

Alive Inside will premiere at the Rubin Museum of Art in New York City on April 18.

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