Faculty of Health Professor Lauren Sergio and PhD candidate Kara Hawkins who led the study asked the participants to complete four increasingly demanding visual-spatial and cognitive-motor tasks, on dual screen laptop computers. The test aimed at detecting the tendency for Alzheimer’s in those who were having cognitive difficulty even though they were not showing outward signs of the disease.
“We included a task which involved moving a computer mouse in the opposite direction of a visual target on the screen, requiring the person’s brain to think before and during their hand movements,” says Sergio in the School of Kinesiology & Health Science. “This is where we found the most pronounced difference between those with mild cognitive impairment (MCI) and family history group and the two control groups.”
Hawkins adds, “We know that really well-learned, stereotyped motor behaviours are preserved until very late in Alzheimer’s disease.” These include routine movements, such as walking. The disruption in communication will be evident when movements require the person to think about what it is they are trying to do.
For the test, the participants were divided into three groups – those diagnosed with MCI or had a family history of Alzheimer’s disease, and two control groups, young adults and older adults, without a family history of the disease.
The study, Visuomotor Impairments in Older Adults at Increased Alzheimer’s Disease Risk, published in the Journal of Alzheimer’s Disease, found that 81.8 per cent of the participants that had a family history of Alzheimer’s disease and those with MCI displayed difficulties on the most cognitively demanding visual motor task.
“The brain’s ability to take in visual and sensory information and transform that into physical movements requires communication between the parietal area at the back of the brain and the frontal regions,” explains Sergio. “The impairments observed in the participants at increased risk of Alzheimer’s disease may reflect inherent brain alteration or early neuropathology, which is disrupting reciprocal brain communication between hippocampal, parietal and frontal brain regions.”
“In terms of being able to categorize the low Alzheimer’s disease risk and the high Alzheimer’s disease risk, we were able to do that quite well using these kinematic measures,” says Hawkins. “This group had slower reaction time and movement time, as well as less accuracy and precision in their movements.”
Hawkins says the findings don’t predict who will develop Alzheimer’s disease, but they do show there is something different in the brains of most of the participants diagnosed with MCI or who had a family history of the disease.
York University is helping to shape the global thinkers and thinking that will define tomorrow. York’s unwavering commitment to excellence reflects a rich diversity of perspectives and a strong sense of social responsibility that sets us apart. A York U degree empowers graduates to thrive in the world and achieve their life goals through a rigorous academic foundation balanced by real-world experiential education. As a globally recognized research centre, York is fully engaged in the critical discussions that lead to innovative solutions to the most pressing local and global social challenges. York’s 11 faculties and 27 research centres are thinking bigger, broader and more globally, partnering with 288 leading universities worldwide. York’s community is strong − 55,000 students, 7,000 faculty and staff, and more than 250,000 alumni.
Gloria Suhasini, York University Media Relations, 416 736 2100 ext. 22094