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Are there universal expressions of emotions?
The 40 or so muscles in the human face can be activated in different combinations to create thousands of expressions. But do these expressions look the same and communicate the same meaning around the world regardless of culture? Is one person’s smile another’s grimace? Sophie Zadeh investigates.

You aren’t at the mercy of your emotions
Can you look at someone's face and know what they're feeling? Does everyone experience happiness, sadness and anxiety the same way? What are emotions anyway? For the past 25 years, psychology professor Lisa Feldman Barrett has mapped facial expressions, scanned brains and analyzed hundreds of physiology studies to understand what emotions really are.

How stress affects your body
Our hard-wired stress response is designed to give us the quick burst of heightened alertness and energy needed to perform our best. But stress isn’t all good. When activated too long or too often, stress can damage virtually every part of our body. Sharon Horesh Bergquist gives us a look at what goes on inside our body when we are chronically stressed.

Can machines read your emotions?
Computers can beat us in board games, transcribe speech, and instantly identify almost any object. But will future robots go further by learning to figure out what we’re feeling? Kostas Karpouzis imagines a future where machines and the people who run them can accurately read our emotional states — and explains how that could allow them to assist us, or manipulate us, at unprecedented scales.

Why do we feel nostalgia?
Nostalgia was once considered an illness confined to specific groups of people. Today, people all over the world report experiencing and enjoying nostalgia. But how does nostalgia work? And is it healthy? Clay Routledge details the way our understanding of nostalgia has changed since the term was first coined in the late 17th century.

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