Scientists from the Netherlands Institute of Neuroscience have discovered characteristics of immature neurons in people who were able to maintain cognitive function in the face of brain changes typical of Alzheimer's disease. characteristics. The differences mainly related to the activity of the cells, not their number. The results of the research were published in the journal "Cell Stem Cell". Alzheimer's disease is not always manifested by the same symptoms. Some people have characteristic pathological changes at postmortem examination, even though they did not develop dementia during life. Such preservation of functions is called cognitive stability. The researchers compared hippocampal samples from the Netherlands Brain Bank. Three groups were included in the analysis: donors without pathological changes, patients with dementia caused by Alzheimer's disease, and persons with pathological changes but preserved cognitive abilities. � With the help of gene activity analysis and special computational methods, the scientific group discovered rare cells with characteristics characteristic of immature neurons. They were recorded in all three groups, including donors with an average age of over 80. The scientists expected that there would be significantly more of these cells in people resistant to dementia. However, the quantitative differences were smaller than expected. The most obvious difference appeared at the molecular level. in stable donors, the processes of cell survival and response to injuries were better preserved, and the signals of inflammation and cell death were weaker. The authors hypothesize that immature neurons may support the surrounding tissue and help maintain neural networks. The presence of immature cells does not prove that they were recently formed, or that new neurons are continuously generated in the aged brain. Further work should clarify how these cells interact with neighboring cells and whether they actually participate in the process of protecting against dementia.