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Researchers Surprised by How the Brain and Body React to Anger-Inducing Phrases
New research on the physiology of anger suggests that the part of the brain that’s more active when people are angry is also associated with feelings of “closeness” and positive emotions. The results are surprising: one might guess that anger would be associated with just the opposite (that areas of the brain associated with isolation and negative emotion might be activated).
Neus Herrero and colleagues from the University of Valencia induced anger in 30 right-handed male (more on that below) college students by having them read a set of first-person phrases previously shown to have this effect. The phrases began neutrally, and progressed to more and more emotionally charged statements. A neutral phrase, write the researchers, might be: “Today is no different from any other day”. The authors also give examples of phrases on the other end of the spectrum: “‘I can feel my body getting tense with anger’, ‘I feel like striking out at someone who has angered me’, ‘I am consumed with hatred’.”
The researchers measured the men’s cardiovascular response (heart rate and blood pressure), hormones levels (the stress hormone cortisol and testosterone), and also tested which side of their brains were more active; all variables were measured before and after the anger challenge. The men were also asked to fill out a standard questionnaire that measured their anger level after the test was done.
Not surprisingly, the men reported high levels of anger, and the researchers found an “increase in cardiovascular reactivity,” and in testosterone levels. Surprisingly, however, the researchers also found that cortisol levels actually decreased when the men got angry. The authors say that many other researchers have observed similar decreases in cortisol in angry participants – but since other studies have observed a short term increase in cortisol levels, more research will have to be done to tease this apart.
Interestingly, the team also found that the left hemisphere of the brain was more active under angry conditions. The authors say that one theory, called the motivational direction model “links approach-related emotions (as anger) to the left hemisphere.” Approach-related emotions are those that make us want to be closer to the stimulus at hand. Though this may seem counter-intuitive in the case of anger, in a news release, Herrero explains the phenomenon by saying that “[n]ormally when we get angry we show a natural tendency to get closer to what made us angry to try to eliminate it.”
The authors suggest that future work should include women as well as lefties to see if the results hold true in a more generalized way.
The study was published in the May 31, 2010 issue of Hormones and Behavior.
June 11, 2010
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