11/04/2012 07:01 BST | Updated 11/06/2012 06:12 BST

Author Oliver Sacks' 'Alive Inside' Documentary Shows Power Of Music To Help The Elderly

Our favourite YouTube hit this week is an inspiring clip from a new film called Alive Inside.

Racing towards a million views and circulating quickly on Twitter, it follows the efforts of an American social worker called Dan Cohen and the author Oliver Sacks to explore the therapeutic benefits music can have on the elderly.

In the clip, a man called Henry is introduced. At first, he sits with his head on his desk, withdrawn and unable to communicate - a distant shadow, according to his daughter, of a man who once sang and danced his way through life.

Cohen and Sacks then hands Henry, who suffers from a degenerative disease, an iPod full of music from his era, and he instantly he begins to sing along and move in time to the music. What happens next is extraordinary.

"Immediately he lights up. His face assumes expression, his eyes open wide...he's being animated by the music," as Sacks describes it.

Henry then appears to be a man transformed, and goes on to speak passionately about his favourite music and the affect it has had on him.

The effect on Henry seems to support many of the theories Sacks put forward in his 2007 book Musicophilia: Tales of Music and the Brain in which he argued that music is intrinsic to our neurological makeup and can be used as treatment.

Whatever the science, it's a remarkable and moving moment that highlights how powerful music - and perhaps art in general - can be.

Cohen's Music & Memory organization is soliciting donations of used and new iPods to put music in the hands of nursing home patients across the country. His documentary Alive Inside is slated to premiere on 18 Apri at the Rubin Museum in New York.