When Tony Bennett’s family ,announced in February he had Alzheimer’s disease, few could have guessed that the 94-year-old singer would still hold two major concerts — performing dozens of songs for huge audiences and recalling all the lyrics. However, when it comes to music and the brain, there is a very special link.

“When it was time to rehearse, something incredible happened,” anchor Anderson Cooper relayed in a moving ,60 Minutes feature about Bennett’s preparation for his career finale. The piano player would dive into the set, and “suddenly, the legendary showman was back,” Cooper observed, performing long sets from memory. Bystanders called it “nothing short of a miracle.” But Bennett’s ability to turn on his memories of music and lyrics in the face of serious Alzheimer’s isn’t such a surprise to neurologists.

Music is a ,powerful memory cue. Hearing a song that carries importance in your life, from a wedding or a prom, elicits this entire memory. And this remains true even when a neurodegenerative disease takes hold. Many people with Alzheimer’s may struggle to remember recent events or conversations. They may forget the names of loved ones. But despite these impairments, remarkably, they are still able to tap into musical memories long after other types of memories fade.

Several ,studies have noted the benefits of music on autobiographical and episodic memory, and even on cognitive function and psychiatric symptoms in healthy people and in Alzheimer’s.

But why is the memory of music left intact while cells in other parts of the brain begin dying?

The Biology of Musical Memory

Music ,stimulates many regions in the brain. This includes the sensory regions that process sound as well as the amygdala, which plays a key role in emotional processing. The amygdala is also important for encoding the emotional qualities of memory. One hypothesis is that these regions of the brain are more resilient to cell death.

In a ,2015 study, researchers mapped the regions of the brain that are activated when we hear familiar songs. The researchers identified specific parts of the brain that respond to these songs in healthy humans. Then, they looked at the brains of people with Alzheimer’s disease. They found that the areas involved in processing these musical memories experience little atrophy or cell death.

In another ,study, photographed-evoked memories declined significantly while musical memories stayed intact. Researchers are recognizing the importance of ,music for “unlocking” memory in Alzheimer’s. Remarkably, researchers are finding that the regions of the brain that help us encode music-associated memories are the last to go in Alzheimer’s.

And that’s what makes ,music therapy such a powerful opportunity to help people, ,even those in later stages of Alzheimer’s, to connect with the memories they still have.

Music Therapy for Alzheimer’s

For these reasons, ,music therapy is not an uncommon intervention for Alzheimer’s symptoms. Throughout the world, there are several ,musical programs aimed at improving the quality of life for people with Alzheimer’s. Approaches may involve passive listening, ,creating playlists of old fa

vorites to spark memories, or even playing or singing music, as Tony Bennett does.

Compared to medicinal treatments and other available therapies, music therapy is enjoyable and easy to administer, and it comes with the added bonus of giving family members the opportunity to bond and reminisce with loved ones. When Bennett took the stage at Radio City Music Hall earlier this year, accompanied by superstar Lady Gaga, he became himself again, his wife Susan recalled to Cooper: “He just turned on. It was like a light switch.”

While Bennett may struggle with his memory due to Alzheimer’s, he never misses a beat when it comes to music. Music therapy isn’t exclusive to musicians — for anyone who has enjoyed music at some point in their lives, it can be a way to channel some of this inspiration to family members navigating their own experience with Alzheimer’s.