Music Strikes a Chord for Brain Health

Medscape

a day ago

Music's influence on the brain is documented in conditions ranging from dementia, to epilepsy. Both music participation and appreciation are tied to improvements in executive function and memory so how close are we to harnessing music as a targeted therapeutic tool.
One researcher at the forefront of this work is Edward Large, PhD, a professor at the University of Connecticut in Storrs, Connecticut, and director of its Music Dynamics Laboratory. He told Medscape Medical News that he is optimistic about research suggesting that music can help, 'not just with depression and anxiety but with more profound neurological and psychological disorders.'
However, he added that music's benefits aren't yet fully understood. Robert Zatorre, PhD, founding co-director of the International Laboratory for Brain, Music, and Sound Research in Montreal, Quebec, Canada, cautions against overstating its therapeutic power.
'Music is not a magic pill; it's not a panacea; it doesn't cure everything,' said Zatorre who is also a professor at the Montreal Neurological Institute at McGill University, Montreal, Quebec, Canada.
Instead, it's important to define under what circumstances music could be beneficial and in what ways. 'And that's where the research is right now' he said.
Robert Zatorre, PhD
One challenge is music's deeply personal nature — what resonates with one person may leave another unmoved. Variables such as culture, age, personal history, social context, and even the nature of the neurological condition can influence how someone will respond to music-based interventions, said Zatorre.
Brain Rhythms and Memory
Large, a former president of the Society for Music Perception and Cognition and a musician himself, believes that one of the most important messages from research is the effect that music has on the rhythm of the brain.
Brain rhythms or waves, also known as neural oscillations, are patterns of brain activity associated with various cognitive processes and behaviors. In healthy brains, slow theta waves (4-8 Hz) and fast gamma waves (30-100 Hz) work together (coupling) to encode and retrieve new memories. Alzheimer's disease (AD) is characterized by disruptions in gamma waves and atypical cross-frequency coupling.
Edward Large, PhD
'Music is really the most powerful stimulus we have for synchronizing brain rhythms,' said Large.
His group is testing whether stimulating synchrony in the gamma frequency can help treat AD. 'That's the frequency at which neurons in the hippocampus synchronize when they're retrieving a memory', he said. Noninvasive, gamma-frequency, auditory-visual stimulation has been shown to improve AD-related biomarkers and memory in animal models.
Large is CEO of Oscillo Biosciences which is developing music based interventions for humans.
He explained how such interventions might work: The individual listens to self-selected music and watches a rhythmic light stimulus that is synchronized to the music as their brain waves are monitored via electroencephalography. The light show works in concert with the music to stimulate theta and gamma neural rhythms and phase-amplitude coupling (See photo).
It takes both the music and the synchronized light to have a similar effect to that seen for transcranial alternating-current stimulation, he said.
An early test of Oscillo Biosciences' music-based intervention for AD
Parkinson's Disease (PD)
In addition to its potential memory boosting, music can help improve motor control.
A music app was shown to improve gait and mood in patients with PD.
Daniel J. Levitin, PhD, a neuroscientist and professor emeritus of psychology at McGill University noted in a recent interview with CBC Radio, that music's steady beat can act as 'an external timekeeper' for patients with PD, helping them to walk better because of the auditory stimulation. For multiple sclerosis (MS), Levitin said that music can activate non-demyelinated circuits in order to help with motor control.
He echoed Zatorre's view that while the idea of a music prescription is appealing, what works best for a patient seems to be highly individualized.
'It's not like there is a single healing song or a list of healing songs,' he said in the interview. Instead, brain scans show that different types of songs can produce 'almost identical' brain activity in the limbic system, which is closely involved in experiencing pleasure, Levitin added.
The Pleasure Principle
The pleasure that music brings may be the source of its positive effects.
'I'm convinced that a lot of the benefits of these musical interventions act via the reward system,' said Zatorre who has conducted several related studies and authored a chapter on ' Musical Enjoyment and the Reward Circuits of the Brain ' for a book on Music and Mind edited by opera singer Renée Fleming.
By engaging the reward system 'it has knock-on effects on a lot of behaviors and cognitions, including social cognition and memory and language,' he said.
Zatorre theorized that music heard by a patient with a memory disorder will activate the reward pathway and simultaneously enhance the retrieval of certain memories. 'That's something that has been observed anecdotally in many patients with neurodegenerative disorders,' he said.
There is evidence that the connectivity of the auditory and reward systems is preserved in people with mild cognitive impairment and early AD opening up a potential pathway for early treatment. 'I'm not sure we're there yet. But it's something that people are excited about,' said Zatorre.
Familiar music tends to elicit a greater neural response, especially in older people, because once we reach a certain age, we know what we like and sticking to that brings enjoyment, which is linked to dopamine, explained Zatorre.
The reward system is highly reactive in younger people. 'We not only fall in love with people [more easily] at that age, we fall in love with all sorts of things and places and movies and music. And that tends to stay with us,' Zatorre said.
Large is currently conducting a functional MRI study in patients with AD that compares music that is self-selected and 'meaningful' to the participants with music that is merely familiar.
The meaningful music activates important parts of the brain such as the auditory cortex, hippocampus, and reward centers more than the familiar music, he reported. 'So if you're trying to have an impact on your brain, I think you should listen to the music that you love.'
Sing Like There's Nobody Listening?
A number of recent studies have suggested that physically participating in music may be even better for the brain than passively listening (Figure).
In a large nested study published last year, playing a musical instrument was linked to better executive function in older adults, with stronger links for woodwind instruments.
Keyboard playing was associated with better working memory compared to not playing any instrument. This study did not show any significant associations between listening to music and cognitive performance but singing was associated with better executive function.
Group singing may be particularly beneficial. A Finnish study tied singing in a choir to enhanced brain-structure connectivity across the lifespan of participants with no neurologic diagnoses at baseline.
Another recent study in 50 patients with chronic aphasia after stroke found that those assigned to participate in weekly sessions of group singing had improved communication and responsive speech production 5 months later compared to those who received standard of care.
'It has to do with the vocal motor control, the ability to control your larynx and your breathing and your articulators, as well as the vocalization that singing requires as opposed to speaking,' said Zatorre, who was not involved with the research.
He added that the social aspect of the intervention is also important, especially the 'singing together with other people who are suffering the same difficulties as you.'
Hope for the Tone Deaf
But what about people with congenital amusia ie, the tone deaf? Zatorre noted that about 50% of people who are tone deaf have perfect rhythm. 'They may not have the pitch correct, but they still are on time. So they can clap, or tap, or march, or dance, along to the beat,' he said.
While many may think they are tone deaf, it's estimated that only 1.5%of the general population have true congenital amusia and even fewer also have no rhythm. 'They may not enjoy the music itself but could enjoy the more social aspects of it. It's enjoying bonding with others, even if you're singing off-key,' said Zatorre.
He pointed out that patients with aphasia usually don't sing very well, 'but that's not the point.' Instead, the goal is improved outcome, he added. As the saying goes 'sing like there's nobody listening.'
Music As Preventive Medicine?
Could music be used as a preventive intervention to stave off, say, dementia in younger at-risk individuals?
'I think the answer is [that] we don't really know,' Large said. Although there are still questions about whether amyloid beta (Aβ) plaques are a cause or a symptom of AD, it's been shown that there is a desynchrony of rhythms in the gamma frequency band before a buildup of Aβ plaques occurs, he explained.
'I think that offers some hope that these rhythm-based therapies might have a preventive impact,' said Large.
Zatorre acknowledged that research on music as a preventive intervention is 'quite scarce,' but noted that adding music can still improve quality of life.
'Music is an important art form that almost all people are sensitive to. If you're having a better quality of life, that will enhance everything. Even if it doesn't prevent the formation of plaques in your brain, you will still have a happier existence. And then if you do develop any type of degenerative disorder, you'll have more tools in your toolbox to help you cope,' he said.
However, Zatorre noted that the same could be said for cooking or exercise or anything else that gives pleasure to an individual.
'I worry that music may have been a bit oversold to people, especially from those who are promoting a website or some type of self-help product. So I think caution is in order,' he said.