Scientists have found higher levels of cortisol, a stress hormone, seem to predict brain function, brain size and performance on cognitive tests. They also found memory loss and brain shrinkage in relatively young people long before any symptoms could be seen

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Scientists have found higher levels of cortisol, a stress hormone, seem to predict brain function, brain size and performance on cognitive tests. They also found memory loss and brain shrinkage in relatively young people long before any symptoms could be seen