People with severe brain pathology can show almost no signs of Alzheimer's disease while others with only mild brain lesions exhibit a considerable degree of clinical symptoms. Researchers put this down to cognitive reserve - the amount of spare capacity in the brain which can be used when other parts are damaged. Researchers from Munich Technical University scanned the brains of 270 people with Alzheimer's disease and found that people who had had more years of formal education showed less loss of cognition even when their brains had obviously lost volume. The results of the study took into account other factors such as genetic characteristics, age, gender and brain infarction.
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