Alzheimer’s patients suffer from severe memory loss and disorientation. One of the areas affected by the disease at an early stage is a brain region that is crucial for navigation, the entorhinal cortex, which contains cells that fire in a spatial grid pattern, the grid cells.
The research team analysed the grid cell system in the entorhinal cortex of young students with and without Alzheimer’s risk genes.
“The risk carriers showed a less stable grid pattern in the entorhinal cortex – many decades before they might develop Alzheimer’s dementia,” said Lukas Kunz, who conducted the experiment at the German Center for Neurodegenerative Diseases in Bonn.
In the risk group, the brain activity in the memory system was generally increased and there was an altered navigation strategy.
“Our studies may contribute to a better understanding of early changes of Alzheimer’s dementia,” said Axmacher. “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.”
L. Kunz, T. N. Schroder, H. Lee, C. Montag, B. Lachmann, R. Sariyska, M. Reuter, R. Stirnberg, T. Stocker, P. C. Messing-Floeter, J. Fell, C. F. Doeller, N. Axmacher. Reduced grid-cell-like representations in adults at genetic risk for Alzheimer’s disease. Science, 2015; 350 (6259): 430 DOI: 10.1126/science.aac8128