Posted on Nov 17, 2014, 6 a.m.
Detection of visuomotor impairments may signal a heightened risk for Alzheimer’s Disease.
A simple test that combines thinking and movement may help to detect heightened risk for developing Alzheimer's disease in a person, even before there are any telltale behavioral signs of dementia. Lauren Sergio, from York University (Canada), and colleagues enrolled a total of 66 study subjects who were divided into three groups – those diagnosed with mild cognitive impairment (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. Subjects completed 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. In particular, 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, was able to identify the most pronounced difference between those with mild cognitive impairment (MCI) and family history group and the two control groups. Reporting that: “Comparing participants at increased [Alzheimer’s Disease] risk with both young and old healthy control groups revealed significant performance disruptions in at-risk individuals as task demands increased. Furthermore, we were able to discriminate between individuals at high and low AD risk with a classification accuracy of 86.4% (sensitivity: 81.8%, specificity: 90.9%),” the study authors submit that: “impairments observed in individuals at increased [Alzheimer’s Disease] risk may reflect inherent brain alteration and/or early neuropathology disrupting the reciprocal communication between hippocampal, parietal, and frontal brain regions required to successfully prepare and update complex reaching movements.”
Hawkins KM, Sergio LE. “Visuomotor impairments in older adults at increased Alzheimer's disease risk.” J Alzheimers Dis. 2014;42(2):607-21.