Karen Li, a Department of Psychology professor, is also interested in developing non-MRI methods to detect neurodegeneration. Her research largely focuses on how our ability to be attentive when multitasking changes with age.
Some of her lab’s studies involve getting people to perform an exercise, such as walking on a treadmill, while doing a cognitive task, such as subtracting by threes.
A common conclusion to come out of Li’s lab is that a multitasking test can actually pick up the beginnings of neurodegeneration with more sensitivity than a test that involves only a cognitive task or only a physical activity. This may be due to the overlapping demands for frontal brain regions during walking and cognitive processing.
“So, then we kind of turn that around and say: ‘Okay, if these are the neural circuits that are getting weaker in aging and in neurodegenerative conditions, then we’re going to find ways to strengthen those circuits,’” says Li, who is a member of the CCNA like Phillips.
Li’s multidisciplinary CCNA team looks at interventions to improve cognition and mobility in older adults. They are currently recruiting for a large clinical trial assessing the impacts of moderate aerobic exercise and resistance training, as well as computerized brain training in people at risk for developing Alzheimer’s.
The hope is to build on her own research and that of others to underscore just how important physical and cognitive exercise is to healthy aging brains. “The new clinical trial also brings in additional factors, such as healthy sleep and dietary practices,” says Li. “This helps acknowledge that supporting and improving brain health to reduce the risk of dementia is multifaceted and multidisciplinary.”
Additional risk factors
The kind of collective work that Li’s team is engaged in is vital when trying to detect and prevent such a complicated umbrella of diseases, says Tremblay. “Especially because we know that dementia is more prevalent in populations that are underprivileged and from ethnic-minority communities. We need a stronger collective approach to try to deal with this.”
The good news is that more researchers are recognizing this, she adds.
Take the brain simulation work that Habib Benali and his team have been doing. Benali says that none of it would have been possible without the expertise of Canadian and international scientists working in artificial intelligence, neuroimaging, computational biology, digital health, genomics, Alzheimer’s research, statistics, epidemiology and other disciplines.
Now his team is even trying to include individuals’ environments in brain simulations, which requires a whole other suite of collaborators.
“If I want to follow a person for 10 years and predict if they are going to develop the disease, I have to include their environment within their physiology,” Benali remarks. “That’s a big, big problem, but this is exactly what my team is developing today.”
Those environmental risk factors can be significant. According to a 2020 report published in The Lancet, 40 per cent of dementia cases can be attributed to 12 potentially modifiable risk factors, including air pollution and low social contact. The other risk factors include less education, hypertension, hearing impairment, smoking, obesity, depression, physical inactivity, diabetes, excessive alcohol consumption and traumatic brain injury.
“The main advice as we get older is to remain physically and cognitively engaged, and to find activities that are motivating for you so that you can minimize your cardiovascular risk factors,” says Phillips. “Do everything your grandmother would have told you to do — stop smoking, eat more vegetables, go outside and get more exercise.”
It’s also important to stay hopeful, she adds. Yes, the raw number of dementia cases is going up, but that is also because there are more people over the age of 65 than there were decades ago.
“In Western countries, the percentage of individuals with dementia in that older age range is actually going down compared with 20 years ago,” notes Phillips. “That’s probably because of a lot of the public-health messaging around cardiovascular risk factors and general increases in education and quality of life. So that’s a good-news piece of the puzzle that we have to remember and keep building on.”
Read this cover feature's sidebar “Wide awake: A growing body of research connects poor sleep with dementia”.