"It's kind of striking that an angry facial expression is consciously valued as a very negative signal by almost everyone, yet at a non-conscious level can be like a tasty morsel that some people will vigorously work for," study co-author Oliver Schultheiss, an associate professor of psychology at the University of Michigan, said in a prepared statement.
He said the findings may help explain why some people are so fond of teasing.
"Perhaps teasers are reinforced by that fleeting 'annoyed look' on someone else's face and therefore will continue to heckle that person to get that look again and again. As long as it does not stay there for long, it's not perceived as a threat but as a reward," Schultheiss said.
He and lead author Michelle Wirth measured testosterone levels in volunteers and then had them do a computer task in which certain complex keyboard sequences triggered different images on the computer screen - an angry face, a neutral face, or no face.
Testosterone makes the differenceMales and females with higher testosterone levels than other members of the same sex learned the angry face sequence better than the other sequences. This did not happen among volunteers with lower testosterone levels.
The association between higher testosterone levels and better learning of the angry face keyboard sequence was strongest when angry faces flashed on the computer screen subliminally - too fast for conscious identification.
"Better learning of a task associated with anger faces indicates that the anger faces were rewarding, as in a rat that learns to press a lever in order to receive a tasty treat. In that sense, anger faces seemed to be rewarding for high-testosterone people but aversive for low-testosterone people," Wirth said in a prepared statement.
The study was published in the journal Physiology and Behaviour. – (HealthDayNews)
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