My research lab sits about a mile from where several bombs exploded during the Boston Marathon in 2013.

The surviving bomber Dakar Sarnia of Chechnya was tried, convicted and sentenced to death. Now, when a jury has to make the decision between life in prison and the death penalty, they base their decision largely on whether or not the defendant feels remorseful for his actions. Sir, I have spoke words of apology. But when jurors looked at his face, all they saw was a stone faced stare.

Now, sir, now I have is guilty, there's no doubt about that. He murdered and maimed innocent people. And I'm not here to debate that my heart goes out to all the people who suffered. But as a scientist, I have to tell you that jurors do not and cannot detect remorse or any other emotion in anybody ever.

Neither can I, and neither can you. And that's because emotions are not what we think they are. They are not universally expressed and recognized. They are not hardwired brain reactions that are uncontrollable.

We have misunderstood the nature of emotion for a very long time. And understanding what emotions really are have important consequences for all of us. I have studied emotions. As a scientist for the past 25 years, and in my lab, we have probed human faces by measuring electrical signals that cause your facial muscles to contract to make facial expressions, we have scrutinized the human body and emotion, we have analyzed hundreds of physiology studies involving 1000s of test subjects, we've scanned hundreds of brains and examined every brain imaging study on emotion that has been published in the past 20 years. And the results of these of all of this research is overwhelmingly consistent.

It may feel to you like your emotions are hardwired and they just trigger and happen to you. But they don't. You might believe that your brain is pre wired with emotion circuits, you know that you're born with emotion circuits, but you're not. In fact, none of us in this room have emotion circuits in our brain. In fact, no brain on this planet contains emotion circuits.

So what are emotions really?

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