Alzheimer's disease patients suffer from severe memory loss and disorientation. One of the brain areas affected by the disease at an early stage is the entorhinal cortex that is crucial for navigation. A new study has revealed that young adults with genetically-increased Alzheimer's risk have altered activation patterns in this brain region (entorhinal cortex) that is crucial for spatial navigation.
A research team led by Nikolai Axmacher from Germany's Ruhr-University Bochum, together with colleagues from the universities of Bonn, Nijmegen and Ulm found an altered grid cell system in the entorhinal cortex of young students with Alzheimer's risk genes.
Lukas Kunz, who conducted the experiment at the German Centre for Neurodegenerative Diseases in Bonn, said, "The risk carriers showed a less stable grid pattern in the entorhinal cortex many decades before they might develop Alzheimer's dementia. Moreover, risk carriers moved less frequently in the center of the virtual landscape, which indicated an altered navigation strategy."
In the high risk group, the brain activity in the memory system was generally increased. the researchers said, "That might be short-term compensation of the reduced grid pattern, but it may also contribute to the development of Alzheimer's dementia in the long term."
Currently, there is no curative treatment for Alzheimer's dementia, as the drugs are only administered after large parts of the brain have been destroyed. This study aimed at identifying Alzheimer's dementia early on and yield a better understanding of early disease stages.
Axmacher said, "Our studies may contribute to a better understanding of early changes of Alzheimer's dementia. Now, it has to be verified if such changes also occur in older people at an early stage of Alzheimer's dementia and if they can be affected by the application of drugs."
The study was published in the Science.