causes of sadness

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Your Crows' Feet Are Frozen
Expressions affect emotions. This means that not being able to frown makes us happier—so found studies on Botox that "froze" between-the-brow furrows. And not being able to smile makes us feel sadder, finds a new study at Cardiff University. After people had the crows' feet around their eyes treated with Botox—which "diminished the strength of their smiles"—they felt significantly more depressed two to four weeks later compared to those who (here's the lesson) treated only their foreheads.