A simple test that combines thinking and movement can help to detect a heightened risk for developing Alzheimer’s disease, even before there are any signs of dementia, according to scientists at York University in Toronto.
For their study, Faculty of Health Professor Lauren Sergio and Ph.D. candidate Kara Hawkins asked participants to complete four increasingly demanding visual-spatial and cognitive-motor tasks on dual screen laptop computers.
The test was designed to detect a tendency for Alzheimer’s in those who are having cognitive difficulty even though they are not showing outward signs of the disease, according to the researchers.
“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,” said Sergio.
“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.”
“We know that really well-learned, stereotyped motor behaviors are preserved until very late in Alzheimer’s disease,” added Hawkins.
She noted this included routine movements, such as walking. The disruption in communication becomes evident when movement requires a person to think about what it is they are trying to do, she explained.
For the test, the participants were divided into three groups — those diagnosed with MCI or with 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 found that 81.8 percent of the participants who 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,” said 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,” added Hawkins.
“This group had slower reaction time and movement time, as well as less accuracy and precision in their movements.”
Hawkins noted 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.
The study was published in the Journal of Alzheimer’s Disease.
Source: York University