Scientists at the Ruhr University in Germany have determined that at the age of 20, the first signs of Alzheimer's disease, an incurable and fatal form of senile dementia, may appear. They are expressed in the peculiarities of how the brain copes with certain memory tests. A new way to determine the risk of disease in the future is reported in the journal Current Biology.
The study involved 82 people with an average age of 20 years. The volunteers had various variants of the ApoE gene associated with low or high risk of Alzheimer's disease. 33 people had an average, 34 increased, and 15 had a lower risk of developing dementia in the future. During the experiment, participants underwent brain imaging while they looked at images of more than 150 household items. Some images were repeated, and the position of objects on them sometimes changed. The subjects had to identify the repeating images and tell if the position of the objects on them changed.
Although all the volunteers successfully passed the memory tests, they showed differences in the activity of the brain, namely the hippocampus, the region responsible for the formation of long-term memory. Different groups of study participants activated the hippocampal subfields in different ways and to varying degrees.
It is currently unclear whether these effects are significant for the development of Alzheimer's disease in old age. However, it is believed that the disease is triggered by an adverse interaction of lifestyle, external factors and genetic risks. The largest genetic factor in dementia is played by hereditary mutations affecting apolipoprotein E (ApoE), a protein responsible for fat metabolism and neuronal function.
