Let's start with a brain exercise. I'm going to ask you to visualize three scenarios. The visualization part is very important, so please close your eyes, take a deep breath and imagine. You're late to catch a flight. You rush through the airport, you make it through security. You run to the gate, you make it down the jetway, you step on the plane just as they close the door behind you and the pilot steps out of a cockpit to say hi.

You get to your destination, you go to a local restaurant, and you have the best meal of your life. I mean, really enjoy this. There's no calories in visualization, . And at the table next to you is a couple happily celebrating their anniversary. The next morning you go to the biggest technology conference in the world, and the CEO of this year's hot, hottest tech startup just took the stage to speak.

Now you should have a solid picture of all of that, so open your eyes because I have some questions for you in your mental image. Was the pilot, black was the married couple, two men. Did the tech CEO on stage look like me? It's okay if one or all of your answers is no. Your brain creates images of what's familiar.

It's less of a fan of what's not familiar. The things I mentioned are generally less familiar. The black pilot, the same sex married couple, the female tech ceo, no matter how much you might love the idea of those things when immediately confronted with them the amygdala, that's the most ancient part of your brain, signals the hypothalamus to fire up the hypo salam pituitary axis, which is where the brain and the endocrine system I.

So at this point, your adrenal glands release cortisol into your bloodstream, which triggers your stress response. This is the physiology of stress according to the Dartmouth Undergraduate Journal of Science, and it happens in a matter of milliseconds long before you have the chance to consciously think, I'm so happy these two men have the freedom to marry who they love.

As Dr. Susan Fisk explains when it comes to unfamiliar social situations, there's ample evidence that encountering something fundamentally different from what we expect elicits a stronger activation in the amygdala than encountering something or someone we perceive as the norm arm. This is what kept our species alive for millions of years.

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