Mind wanders.... How many types of dementia are there?
One is certainly the clinical one, due to aging, accidents etc. On which, we don't have any control as during this stage even the cause also may be difficult to recall.
The other dementia is self imposed. In this stage we loose the self awareness, thereby forget the Dhamma, the teachings, the Sila, the Gratitude and all the good things worthy of a human being.
The former is an effect but the later is a cause with grave consequences........but controllable.