Unlike normal age related memory loss people with Alzheimer's find themselves unable to carry out the ordinary events of daily functioning and become unable to live independently. However in the early stage of Alzheimer's memory impairments and other early symptoms and memory changes of aging can be difficult to differentiate.
Scientists from the University of Illinois have developed a cognitive task that helps identify the differences and can help dictate treatment approaches and exclude other illnesses. As we know the hippocampus, a part of the brain, is important in binding together information of an event where information is stored in different parts of the brain. It is also part of the brain that is affected by Alzheimer's disease. So if someone remembers a person called, for example, Julie, they can then also remember what she looks like by composing a relational memory.
The test that these scientists put together looks at a task that tests participants' relational memory abilities. Young adults, healthy older adults, and individuals with very mild Alzheimer's disease participated in the investigation. They were shown a circle divided into three parts, each had its own unique design. They had to study a circle, one of a series of 10 circles presented one at a time, and pick its exact match.
They found people with very mild Alzheimer's disease did worse overall on the task than those in the healthy aging group. The healthy aging group did worse than a group of young adults. People with very mild Alzheimer's disease were shown to have additional memory impairment indicating the changes in cognition that result from Alzheimer's are qualitatively different than healthy aging. “This unique impairment allows researchers to statistically differentiate between those who did and those who did not have Alzheimer's more accurately than some of the classical tests used for Alzheimer's diagnosis”.
The researchers want to continue looking at the possibility of a unique test for early Alzheimer's that can be used in clinical practice. They also want to use neuroimaging to look at changes in the brain linked to Alzheimer’s and memory change in aging.
Four main differences between normal age-related memory loss and Alzheimer's disease:
- In normal age-related memory loss, a person can usually follow verbal and written instructions without difficulty. As Alzheimer's disease progresses people are increasingly unable to do so.
- In normal age-related memory loss, people can manage their own personal care. They are able to plan what they want to do then carry out their care (called executive functioning). However in people with Alzheimer's disease they lose this ability.
- In normal age-related memory loss, someone might forget a word or part of an event. However given time they eventually do remember. People with mid late stage Alzheimer's disease do not.
- In normal age-related memory loss using reminders is often helpful, but people with Alzheimer's gradually become increasingly less able to benefit from memory aids. This is because the brain damage caused by Alzheimer's is progressive and the damage just gets worse and worse.
Jim M. Monti, David A. Balota, David E. Warren, Neal J. Cohen. Very mild Alzheimer׳s disease is characterized by increased sensitivity to mnemonic interference. Neuropsychologia, 2014; 59: 47 DOI: 10.1016/j.neuropsychologia.2014.04.007