Have you ever noticed that when someone compliments you, say on your nice outfit or your hairstyle, you get a boost of confidence and well-being for a while? That through the rest of that conversation and for an hour or two later, you feel better about yourself and perhaps about the world? And, as an alternative scenario, if someone were to tell you that your outfit today was really sub-par or that you really should spend some more time on your hair in the future, how that would rock your world? And probably for days, if not weeks?
Our Negativity Bias Is Highly Adaptive
As a species, we have survived for millions of years by adapting to very dangerous and threatening conditions. We are highly attuned and sensitive to danger and pain. 
We don’t die from a false positive so we tend to go a bit overboard to protect ourselves. Our taste buds respond more strongly to bitter tastes than to sweet ones to keep us safe. And in the past, we were much more likely to focus on the rustling in the nearby bushes that could be a lion than we were to appreciate the beautiful sunset on the horizon. The folks who focused on the latter typically didn’t survive to pass on their genes. Natural selection not only affected our physical attributes but our psychological disposition as well. Our negativity bias is highly adaptive and has served us well. We wouldn’t be here today without it.
Our Brains Are Velcro For The Bad And Teflon For The Good
The good news is our human circumstances have changed dramatically for the better. Our brains, however, have not. We tend to hold onto our negative thoughts and feelings much longer than our positive ones. As Tal Ben-Shahar, a leader in Positive Psychology, says, “Our brains are Velcro for the bad, and Teflon for the good.” We absorb negative thoughts and feelings more easily and deeply in an attempt to protect ourselves.
Luckily, there are ways that you can combat this negativity bias and turn down your “threat detector” so it’s more in line with our current living conditions.