Last week, we discussed an eye-tracking test that could detect incipient dementia by assessing memory defects. Another new study, this time from the Washington University in St. Louis Alzheimer's Disease Research Center, helps uncover exactly how memory begins to break down in the earliest stages of Alzheimer’s disease.

The Washington University researchers studied 109 healthy elderly subjects and an experimental group made up of elderly subjects suffering from the earliest stages of Alzheimer’s. Both groups were given words with randomly assigned point values, with instructions to prioritize the memorization so as to get the maximum points rather than the most words.

While there was no significant difference between the groups in terms of raw number of words remembered, there was a large difference in the points accumulated. Healthy subjects were able to prioritize and encode important information more efficiently, but the early Alzheimer group indiscriminately remembered and so missed many high value words.

This study brings us closer to understanding the details of why the brain breaks down as Alzheimer’s progresses. As researchers pinpoint specific cognitive functions rather than blanket symptoms like “memory problems”, they may be able to solve the mystery of what physiological factors cause the breakdown. They will also be better able to construct tests to detect Alzheimer’s early and distinguish it from natural aging and other diseases.