Repeated listening to personally meaningful music induces beneficial brain plasticity in patients with mild cognitive impairment or early Alzheimer’s disease, suggests a new study by researchers at the University of Toronto and Unity Health Toronto.
Changes in the nerve pathways of the brain correlated with increased memory performance on neuropsychological tests, supporting the clinical potential of personal, music-based interventions for people with dementia.
The multimodal study was published this week in Journal of Alzheimer’s disease.
“We have new brain-based evidence that autobiographical music – that is, music that is of particular importance to a person, such as the song they danced to at their wedding – stimulates neural connections in ways that help maintain higher levels of functioning. ,” say Michael Thaut, senior author of the study, director of the U of T’s Music and Health Science Research Collaboratory and professor at both the Faculty of Music and Temerty the Faculty of Medicine.
“Typically, it is very difficult to show positive brain changes in Alzheimer’s patients. These preliminary but encouraging results show improvements in brain integrity, opening the door to further research into therapeutic uses of music for people with dementia – both musicians and non-musicians, ”says Thaut, who also holds the Canada Research Chair. in music, neuroscience and health.
The researchers reported structural and functional changes in neural pathways in study participants, particularly in the prefrontal cortex, the brain’s control center, where deep cognitive processes occur. The researchers showed that exposing the brain in patients with early cognitive decline to autobiographical prominent music activated a distinct neural network – a musical network – consisting of different brain areas that showed differences in activation after a period of daily music listening.
They also observed differences in brain connections and white matter, providing further evidence of neuroplasticity.
“Music-based interventions can be a feasible, cost-effective and easily accessible intervention for those in the early stages of cognitive decline,” says Corinne Fischer, lead author, associate professor in the Department of Psychiatry at the Temerty Faculty of Medicine and director of geriatric psychiatry at St. Michael’s Hospital, Unity Health Toronto.
“Existing treatments for Alzheimer’s disease have shown limited benefit to date,” she adds. “While larger controlled trials are needed to confirm clinical benefits, our results show that an individualized and home-based approach to music listening can be beneficial and have lasting effects on the brain.”
For the study, 14 participants – eight non-musicians and six musicians – listened to a curated playlist of autobiographically relevant, long-known music for one hour a day for three weeks. Participants underwent structural and task-based functional MRI before and after the listening period to determine changes in brain function and structure. During these scans, they listened to clips of both long-known and new music. Heard an hour before scanning, the new music was similar in style and yet had no personal significance for the listeners.
When participants listened to the new music, brain activity occurred mainly in the auditory cortex. However, when participants listened to long-known music, there was significant activation in the deeply coded network of the prefrontal cortex, a clear indication of executive cognitive engagement.
There was also a strong involvement in subcortical brain regions, older areas that were minimally affected by Alzheimer’s disease pathology.
The researchers reported subtle but clear differences in structural and functional brain changes associated with music listening in musicians compared to non-musicians, although further studies in larger samples are needed to verify these results. Repeated exposure to music with autobiographical appearance improved cognition in all participants, regardless of musicianship.
“Whether you are a lifelong musician or have never played an instrument, music is a key to your memory, your prefrontal cortex,” says Thaut. “It’s simple: Keep listening to the music you’ve loved all your life. Your favorite songs of all time, the pieces that are especially important to you. Make it your brain exercise.”
The U of T-Unity Health study builds on previous work with the same group of participants who first identified the brain mechanisms that encode and preserve musical memories in people with cognitive decline in the early stages.
Next, the researchers plan to replicate the study in a larger sample and introduce a strong control condition to investigate the role of music in moderating brain reactions, and whether it is the music or the autobiographical content that elicits changes in plasticity.