Some people have the biological hallmarks of Alzheimer’s – proteins called amyloid and tau that gum up the brain – but have no disease symptoms. Researchers suggest that this could be because some people build up a “cognitive reserve” – the brain’s ability to find new ways to handle and overcome problems.
People with greater cognitive reserve seem to be better at staving off dementia symptoms, but when stress levels are high or persistent, they can weaken this reserve by making it less likely that they will socialise and less likely that they will be physically active – both of which are known to protect against dementia.
