In the absolute moment where your perception is untouched by mental judgements of whatever is happening right now, haven reveal itself right there where you are perceiving the life pristine and innocent.
Your perception is not to be improved but to let go what keeps you from seeing clearly, that which you let go is from within diging deep into the nature of who you are which ultimately is formless being that you are.
What happens with this life that sees this whatever it perceives is your responsibility so wake up and see what you are doing to yourself.
I am not one of the brain experts but from personal inner inquiry of the spiritual experience the brain is not what they say, at least you are not forced to believe the following non-sense.
Instead of recycling past experiences try to live this experience called life more intensly without looking through the veil of past at this very present moment in which you find yourself in right now.