Putting more brain in the bank
Cognitive reserve can protect you from the effects of Alzheimer's and other diseases that affect the brain.
Consider two older people with the same amount of Alzheimer's disease–related plaques and tangles in their brains. One person has some memory miscues now and then, but continues to lead a normal life. The other has the severe loss of memory and other cognitive deficits that come with Alzheimer's disease. Why the difference? One explanation is that they had differing amounts of cognitive reserve.
Cognitive reserve can be thought of as having two parts, hardware and software. The hardware consists of brain cells and connections between those brain cells, which are called synapses. The theory is that people with more brain cells and synapses at their disposal are better able to maintain cognitive functions even after important brain cells are damaged.