He he , not sure about battery drainage, never heard about it. Our brain , apart from the sentient part , is like any computing device. The brain also gets trained (in a cognitive manner) by the data it receives from the environment and surrounding. Live with people who believe in ghosts and keep spreading supposed stories about ghosts and there you are! A trained brain with lot of "supposed" data about ghosts.
As far as regrets and doing right is concerned, we should anyways do it. Because it affects real people. Because righting a wrong is what we should do. We are gifted with that power to differentiate..many other species can't.
And if you still want to believe in an after life , please train the brain to believe in a life where you find fulfillment, happiness, and eternal bliss..not some ghostly stuff..
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