It seems that we humans are programmed to remember the negative. It is thought that this may be a survival mechanism from the time when had to be on alert for danger at all time.
Your brain preferentially scans for, registers, stores, recalls, and reacts to unpleasant experiences; it's like Velcro for negative experiences and Teflon for positive ones. Negative experiences do have benefits: Loss opens the heart, remorse provides a moral compass and anxiety alerts you to threats. But emotional pain with no benefit to yourself or others is pointless suffering and pain today breeds more pain tomorrow. For instance, according to research by psychiatrist Vladimir Maletic, even a single episode of major depression can reshape circuits of the brain to make future episodes more likely
One way to balance this is by cultivating gratitude.
Here is a gratitude exercise developed by Dr. Srikumar Rao which I particularly like and find very affective.
Recall yesterday. Begin when you woke up in the morning think of something you were genuinely grateful for (it could be the warm bed you were lying in, the fact that you had a bed, that you were alive for another day) whatever you truly feel grateful for. Now close your eyes and really experience that feeling , feel it all through your body if possible. Next move on to your time in the bathroom are you grateful for the warm water or maybe it is the toothpaste that leaves your mouth feeling fresh and wonderful.What about breakfast is there some good coffee to drink? Move through your day like this. Was there anything to be grateful for at your work? Now move to the evening. Did you enjoy your evening meal or maybe it was the drink before bed. Review it all and allow yourself to feel genuinely grateful.
I can guarantee that if you practice this exercise before going to bed you will sleep really well and if you're like me you will wake up in great form.
I have been practicing this exercise for a few weeks and can see how it has made me more conscious of all the good things in my life. Now the feeling of gratitude pops spontaneously into my mind more and more often.