IN THE EARLY 20th century, coal miners brought caged canaries into the mines with them as a warning device for noxious gases. When the canaries would begin to behave unusually, the coal miners would know to leave the mines for fear of being overcome by deadly levels of carbon monoxide. Now, in the 21st century, scientists are looking for their own "canaries," in this case to mark early signs of Alzheimer disease (AD). Identifying persons at risk of developing AD is an extremely important issue and is relevant for potential therapeutic interventions,1 with the goal of delaying disease onset and ultimately limiting the number of persons afflicted with this devastating disorder.2 To delay disease onset, we must gain knowledge about the course of AD prior to its diagnosis, the preclinical phase of AD.
Small BJ, Fratiglioni L, Bäckman L. Canaries in a Coal MineCognitive Markers of Preclinical Alzheimer Disease. Arch Gen Psychiatry. 2001;58(9):859-860. doi:10.1001/archpsyc.58.9.859