Is dimentia promoted when someone doesn't use their brain?

Interesting question: Maybe yes, according to the religious orders study from rush-presb-st lukes, in chicago. Risk of alzheimers increased in those with less education, less reading, less activity requiring thought provocation, lower iq, and less physical activity. So, maybe brain is like a muscle, and needs repetitive exercise.

Possibly: There is some evidence that keeping brain active decreases risk of alzheimer's disease. However, more important for decreasing risk is probably physical exercise.