Testosterone Promotes Aggression Automatically

New research suggests that testosterone may make us more aggressive without us consciously feeling any aggression. Christie Nicholson reports

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Testosterone has a lot of roles—some good, some perhaps counterproductive. Now research suggests that testosterone can make people more poised for aggression, even if they’re not feeling feisty.

Study participants received testosterone or a placebo and then were shown color-tinted faces of men and women. The faces had subtle differences that made each one look angry, happy, or neutral.

When scientists changed the color of the face, the study subjects were asked to look at a circle of the same color below the face. Those who got the testosterone boost diverted their gaze from the angry faces more slowly than from the happy or neutral faces—an aggressive move. Subjects who got the placebo did not show this behavior.


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None of the participants reported recognizing any faces as having a specific facial expression, suggesting that the recognition of the angry face was subconscious. And none of the subjects reported mood changes after receiving the testosterone.

It used to be thought that testosterone drives social dominance by imparting an awareness of feeling superior and strong. But this study shows that testosterone might be an unconscious driver, motivating social dominance as it does in other animals, involuntarily and automatically.

—Christie Nicholson

[The above text is an exact transcript of this podcast.]

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