Old music jogs memories for Alzheimer’s patients
Familiar sounds can provide cognitive boost to mildly impaired brains
TORONTO — It’s long been known that Alzheimer’s patients often retain musical memories, even when recall of names, faces and places has been lost as the disease relentlessly destroys key areas of the brain.
Now Canadian researchers believe they know why, thanks to the power of MRI brain scanning.
Toronto scientists enrolled 20 people with early-stage Alzheimer’s or mild cognitive impairment in a study to discern what was occurring in their brains while they listened to familiar music and a composition they had never heard before while having MRI scans.
When subjects listened to the previously unknown composition, it lit up a region of the brain known as the temporal lobe, “which is what we would have predicted because that part of the brain gets activated when you listen to anything,” said principal investigator Dr. Corinne Fischer, director of the memory disorders clinic at St. Michael’s Hospital.
But when participants listened to familiar music — selections from a playlist of songs they had chosen going back at least 20 years — there was a much more extensive pattern of activation of several areas of the brain, including those involved with emotion and the processing of language, movement and memory.
“There’s always been this question of why music and the ability to appreciate music is preserved, even in the latest stages of Alzheimer’s disease,” Fischer said.
“And I think one of the things this tells us is that it may be not so much the music as it is that familiar aspect of the music and the fact that that’s activating parts of the brain that aren’t typically damaged by Alzheimer’s pathology.
“So that’s why even though you might not know your name, you may not know your environment, you may still be able to appreciate a song because it’s activating those areas that are not damaged.”
Lead author Michael Thaut, a professor of music and neuroscience at the University of Toronto, said it’s common for people in even relatively advanced stages of Alzheimer’s to call to mind the melodies and lyrics of songs from their past, as well as the autobiographical memories attached to the music.
“They remember quite a bit of music,” he said, adding that someone might say “‘Yes, this is Duke Ellington’ or ‘This was my favourite music when I went out with my wife.’
“But up to this point, we had no idea what the brain mechanisms are that drive these very long-lasting memories.”
That’s why the researchers have been excited about their findings, which were presented at a recent Society for Neuroscience conference in San Diego.
For Colleen Newell, taking part in the research confirmed something she had long suspected — that her memory problems and difficulty with organization were signs of cognitive impairment.
“Not only did I recognize I was dropping (forgetting) nouns, but that my mother has Alzheimer’s,” said the 60-year-old guitarist, pianist and songwriter, one of about five professional musicians included in the research.
“She’s 80, and she was having similar memory issues at my age. So I wanted to have a baseline to see what was going on.”
As part of the research, subjects were asked to listen to their playlist for an hour a day for three weeks, while trying to recollect associated life events and discussing them with family members or caregivers.
They were then cognitively tested and also had their brains scanned again.
“What we found was there was improvement in brain functional connectivity, changes in brain activation and also improvements in memory scores, which told us that by exposing the brain repeatedly to this familiar music, people were actually improving cognitively and there was evidence that their brain was also changing,” Fischer said.
Connectivity is a measure of information flow between different brain regions, an important component of neurological function; enhanced connectivity and the other changes suggest that repeatedly listening to familiar music may give the Alzheimer-affected brain a cognitive boost, Thaut said.