A study at the University of Arizona that shows how well people remember past events in their lives could help physicians predict early on who is at risk for developing Alzheimer's disease.
The researchers administered a "autobiographical memory" test to a group of 35 healthy adults, approximately half of whom carry the gene variant APOE e4 ̵
Sometimes as a disease with a clinically silent beginning, Alzheimer's is difficult to detect early, although changes in the brain associated with the disease may begin to play years or even decades before an individual begins to show memory difficulties, said UA neuropsychologist Matthew Grilli, principal author of the new research published in the Journal of the International Neuropsychological Society .
"This presents a major challenge for the development of effective treatments," said Grilli, assistant professor and director of the Human Memory Laboratory in the UA Department of Psychology. "The hope is that in the near future, we will be receiving medications and other treatments that may slow, stop and even reverse some of the brain changes we consider to be the hallmark of Alzheimer's disease." The problem is, we are […]
Grillis' goal is to catch brain changes much sooner before they have an obvious effect on cognition and memory.
He and his UA colleagues Aubrey Wank, John Bercel and Lee Ryan decided to focus on autobiographical memory or people's memories of past events in their lives, as this type of memory relies on areas of the brain, who are prone to early changes from Alzheimer's disease.
"When we retrieve these complex types of memories that have multimodal details, they are very much alive or rich, they come with narratives, context, and background stories," Grilli said. "We have learned through cognitive neuroscience that the ability to reproduce these memories in the mind depends on a widely distributed network in the brain and is critically dependent on regions of the brain that we know are early in Alzheimer's disease
In autobiographical interviews, study participants aged 50 to 80 were asked to recall the most recent memories, childhood memories, and early adulthood memories in as much detail as possible. The interviewers – who did not know which participants had a genetic risk factor for Alzheimer's disease – recorded and evaluated the participants' responses, and evaluated which details contributed to the fullness and vividness of the memories and which did not.
Those with the genetic risk factor for Alzheimer's disease described as a group memories with much less detailed details than those without the risk factor, although all study participants worked normally and comparably on a battery of other, standard neuropsychological tests.
"None of these people would be diagnosed with dementia or mild cognitive impairment," Grilli said. "They are clinically normal, they are cognitively normal, but there is this subtle difficulty a group has in recalling real-world memories, which we think is because there are more people in the group who are in a preclinical Stage of Alzheimer's disease. " Not everyone with the gene variant APOE e4, which is found in about 25 percent of the population, will contract Alzheimer's, and not everyone who develops Alzheimer's will have the gene.
"From this study, we can not disclose a person and say for sure that person is in the preclinical phase of Alzheimer's disease, which is the next stage of the work we need to do," said Grilli. "But we know that as a group, there are likely to be more people in the e4 vehicle group that are in the preclinical phase of Alzheimer's disease, and we think it was harder to create those memories."
Grilli said The next step is to investigate brain activity in people who are getting vivid autobiographical memories to see if they can observe changes in the brain structure or activation of brain areas affected by Alzheimer's  led to the development of a clinical test that is sensitive enough to preclinical brain changes in Alzheimer's disease and could be used to identify individuals who should undertake a broader study of the pathogenesis of early Alzheimer's disease
Testing for early signs of Alzheimer's disease is invasive and expensive, so this new cognitive test could potentially be used as a screen, "said Grilli. "It could also be used to support clinical trials, and it is currently very difficult and expensive to conduct clinical trials on new medicines because it takes a long time to see if this drug affects memory, or if we have more we might get answers earlier, especially if we try to administer drugs before obvious signs of memory impairment are detectable. "
The personality changes during the transition to a mild cognitive impairment
Matthew D. Grilli et al., Evidence for Reduced Autobiographical Memory Episodic Specificity in Cognitively Normal People of Middle Aged and Older People at Risk for Alzheimer's Dementia, Journal of the International Neuropsychological Society (2018). DOI: 10.1017 / S1355617718000577