Humans are uniquely able to produce and enjoy music—very few other animals can do so. But not only is music one of the fundamental ways we bond with each other, it literally shapes our brains. Perhaps this is so because musical activity involves many parts of the brain (emotional, motor, and cognitive areas), even more than we use for our other great human achievement, language. This is why it can be such an effective way to remember or to learn. It is no accident that we teach our youngest children with rhymes and songs. As anyone who can't get an advertising jingle or a popular song out of their head knows, music burrows its way deep into the nervous system, so deep, in fact, that even when people suffer devastating neurological disease or injury, music is usually the last thing they lose.
I have seen this over and over again in my practice as a neurologist. The right sort of music can literally unlock someone frozen by Parkinson's disease, so that they may be able to dance or sing, even though, in the absence of music, they may be unable to take a step or say a word. For many people with aphasia, a loss of the use of language most commonly caused by stroke, songs can be the key to retrieving words they cannot otherwise utter. People with Tourette's syndrome, who may be distracted by physical and sometimes verbal tics, often find that music allows them to bypass those tics. I have seen people with extreme forms of amnesia who are unable to remember what happened to them a few minutes ago but are nonetheless able to sing or play long, complicated pieces of music, or even to conduct an orchestra or choir.
Perhaps most remarkably, people with Alzheimer's disease and other dementias can respond to music when nothing else reaches them. Alzheimer's can totally destroy the ability to remember family members or events from one's own life—but musical memory somehow survives the ravages of disease, and even in people with advanced dementia, music can often reawaken personal memories and associations that are otherwise lost.
Recently, I met Mary Ellen Geist, a former WCBS radio anchor who has written a book, Measure of the Heart. She contacted me about her father, Woody, who began to show signs of Alzheimer's 15 years ago, at the age of 67. Now, she said, "he can't remember much of anything about his life. He has no idea what he did for a living, where he is living now, or what he did 10 minutes ago. Almost every memory is gone. Except for the music." Mary Ellen brought her father and her mother to New York to meet me. Mr. Geist walked into my office carrying a neatly furled newspaper—though he did not seem to know what a newspaper was. He was well-groomed and nattily dressed, though this, his daughter later told me, had required supervision, for left alone, he might put on his pants backward, not recognize his shoes, shave with toothpaste, and so on. Yet there was a deep civility and courtesy in Woody (as he immediately introduced himself).