It is more that the higher you start the more your cognition can decline before you have symptoms that are bad enough to be diagnosed. If you started out with a

It is more that the higher you start the more your cognition can decline before you have symptoms that are bad enough to be diagnosed. If you started out with a youthful g of 150 and you declined to 100 then no doctor would even notice, but if you started at 75 then a decline to 65 will be catastrophic.