Anger is a form of ignorance ... When you only see something from your own perspective and you fail to acknowledge that there's another perspective, you are ignorant of something, and what you're ignorant of is the fact that you exist in a complicated network of connections to other people.

One reason that the rate of adolescent depression is so high in this country is because adolescents go to bed late. They're on their computers and their devices, which [emit] light at a particular frequency that stimulates their retinas to keep them awake. So, it's disrupting their circadian rhythm ... And then they have to get up at a really early time in the morning to get to school ... An adolescent brain needs ten hours [of sleep] a night, [but] most kids are getting five [or] six hours. That's really bad.

When someone else gets worked up, you're more likely to get worked up too, and if you don't want to be worked up, you don't want that person to be worked up. So, a lot of times when people say 'don't be sad' or 'don't be angry,' really what they're saying is 'I don't want to deal with you being angry or sad, and I don't want to feel that way, so I want you to calm down.'

When it comes to emotion, as with almost everything in biology, variation is the norm. There isn't one anger; you have a whole population of angers that you can feel. And your brain doesn't conjure them randomly; it conjures them according to your brains best guess of what's going to work in a particular situation.

If there was only one thing that you could do in your life... it would be sleep a decent amount everyday—whatever that means for you. It's usually somewhere between seven and eight hours for most adults, and it's longer for kids and adolescents.

An infant brain is not a miniature adult brain ... When human infants are born, they're born with unfinished brains, and those brains are waiting for wiring instructions from the world ... The brain needs information from your eyes in order to finish wiring itself so you can see, and if it doesn't receive that information after you're born, you will never see normally.

The way I would define emotion is the way I would define thinking. What is a thought? What is a belief? What is memory? Your brain is conjuring all of these events in exactly the same way—it's just using different information to make sense of what's going on in the immediate moment.

The way that people move their faces in moments of expression is highly variable ... People scowl about 35% of the time when they're angry, which is more than chance ... But that means 65% of the time, people are moving their faces in other meaningful ways that's not scowling.

In our culture, people believe that they can read mental states of other people by their face, and they believe it so much that it's enshrined in the legal system. And there are people who lose their lives because juries believe that they can read remorse or the lack of it.

It's often the case, I think, in my experience in the science of emotion, but elsewhere too, that scientists in their efforts to make their work meaningful to people will try to interpret their findings in ways that the average person would find interesting.

I was the only one in this group of the five of us who my starting hypothesis was that facial movements are meaningful but there's no one-to-one correspondence between a particular facial configuration, like a scowl, and anger.

Being wrong is—no one likes to be wrong—but for scientists to admit they're wrong is hard, and it's something that we should encourage each other to do, I think, more publicly.

Half of this scowls that people make are not related to anger.

You can take anybody, deprive them of sleep—maybe they get five or six hours a night instead of eight for a couple of nights—and they just become more reactive.

The most expensive organ you own is your brain. Your brain costs you 20% of your metabolic budget. There's no other organ that comes close to being that expensive. Neurons are really expensive little cells to keep alive.

Scientists identify biological signals by what we believe them to mean psychologically. So, 'serotonin is a happiness chemical.' No, serotonin evolved as a metabolic regulator. It is a metabolic regulator.