Researchers from the University of Valencia have been making 30 Spanish men angry to see what happens. The researchers were looking to see what happens in people's brains and bodies rathe than how they behaved. They read the men 50 phrases designed to make them angry. They found that when the men got angry their heart rate, arterial tension and testosterone production increased and their levels of the stress hormone cortisol decreased. The left hemisphere of the men's brains became more stimulated, especially in the frontal and temporal lobes.
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