Researchers from Loughborough University in England have discovered that a loss of visual sensitivity can foretell dementia issues 12 years prior to onset.
The study focused on 8,623 healthy people who were followed up with over the course of several years. At the end of the study period, 537 participants had developed dementia so researchers were able to evaluate what factors lead up to the diagnosis.
Participants were given a visual sensitivity test at the onset of the study, which involved pressing a button as soon as they saw a triangle forming in a field of moving dots. Participants who eventually developed dementia responded much more slowly to seeing the triangle than those who did not develop dementia.
Researchers believe that that the areas of the brain associated with vision may be the first areas affected by the toxic amyloid plaques that are the hallmark of Alzheimer's disease. Other visual processing aspects that are affected by Alzheimer's are contrast sensitivity and the ability to discern between certain colors and people may not become aware of these subtle changes immediately. Vision tests, therefore, have the potential of finding deficits before memory tests do.
