Emotions are not reactions to the world. You are not a passive receiver of sensory input but an active constructor of your emotions. From sensory input and past experience, your brain constructs meaning and prescribes action. If you didn’t have concepts that represent your past experience, all your sensory inputs would just be noise. You wouldn’t k

This is one of the most surprising things I learned as I began to study neuroscience: a mental event, such as fear, is not created by only one set of neurons. Instead, combinations of different neurons can create instances of fear. Neuroscientists call this principle degeneracy. Degeneracy means “many to one”: many combinations of neurons can produ

“No man ever steps in the same river twice,”

In short, we find that your emotions are not built-in but made from more basic parts. They are not universal but vary from culture to culture. They are not triggered; you create them. They emerge as a combination of the physical properties of your body, a flexible brain that wires itself to whatever environment it develops in, and your culture and

And consider this fun fact: the historical record implies that ancient Greeks and Romans did not smile spontaneously when they were happy. The word “smile” doesn’t even exist in Latin or Ancient Greek. Smiling was an invention of the Middle Ages, and broad, toothy-mouthed smiles (with crinkling at the eyes, named the Duchenne smile by Ekman) became

Simulations are your brain’s guesses of what’s happening in the world. In every waking moment, you’re faced with ambiguous, noisy information from your eyes, ears, nose, and other sensory organs. Your brain uses your past experiences to construct a hypothesis—the simulation—and compares it to the cacophony arriving from your senses. In this manner,

Your river of feelings might feel like it’s flowing over you, but actually you’re the river’s source.

This is not to say that Romans never curled up the edges of their mouths in a formation that would look to us much like a smile; of course they did. But such curling did not mean very much in the range of significant social and cultural gestures in Rome. Conversely, other gestures, which would mean little to us, were much more heavily freighted wit

A constructionist approach to emotion has a couple of core ideas. One idea is that an emotion category such as anger or disgust does not have a fingerprint. One instance of anger need not look or feel like another, nor will it be caused by the same neurons. Variation is the norm. Your range of angers is not necessarily the same as mine, although if