Anger & Aggressive Behavior

Negative emotions, except anger, provoke withdrawal, say University of Valencia researchers in the March 2010 issue of "Hormones and Behavior." "The case of anger is unique because it is experienced as negative but, often, it evokes a motivation of closeness," explains lead researcher Neus Herrero. The researchers suspect that the motivational pattern of anger reflects a natural inclination to move toward what made us angry in order to try to eliminate it. The finding supports the notion that a good fight can bring people closer. On the downside, anger and aggression can cause violent behavior, social rejection and sudden death.

Chemical and Neural Responses

The Valencia researchers' conclusions were based on a study that induced anger in 30 men in order to examine hormone changes and brain activation patterns. The study showed that when we get angry, heart rate, artery tension and testosterone production increase, stress levels decrease, and the left frontal lobe of the brain becomes more active. The study contradicts the earlier finding that left frontal areas are involved in experiencing positive emotions, whereas right frontal areas are involved in experiencing negative emotions. When we are angry, we don't dwell on negativity but are more focused on taking action, and this triggers activity in the left hemisphere, the researchers explain.

Impaired Moral Judgments

Brain areas involved in making moral judgments are often impaired in aggressive people, report researchers at the University of Pennsylvania. Cognitive psychologist Adrian Raine and his colleagues looked at brain scans of 792 participants with an aggression problem. They found that these individuals had impairments to prefrontal brain areas involved in decision making, brain regions in the amygdala that process negative input, and regions in the angular gyrus involved in calculating. Raine emphasizes that the findings raise a "significant neuroethical issue" concerning the level of punishment for persistently aggressive people.

Life-Threatening Heart Disease

Anger and aggression are significantly correlated with an increased risk of coronary heart disease, reports public health expert Yoichi Chida from University College in London. Dr. Chida and his colleague Andrew Steptoe completed a quantitative review and meta-analysis of 43 studies linking anger and heart disease. They found that anger and aggression predicted a 19 to 24 percent increase in the likelihood of coronary heart disease.

Anger Rewards

Anger in others can be "like a tasty morsel that some people will vigorously work for," says University of Michigan psychology professor Oliver Schultheiss. Schultheiss and Michelle Wirth, a postdoctoral researcher at University of Wisconsin, Madison, found that high-testosterone people learned a complicated sequence quicker when an angry face followed than when a neutral or happy face did. Low-testosterone people did not learn faster. The difference was even greater when the faces were shown at a level below conscious awareness. Triggering anger in another person is one way to dominate them. This can feel like a reward to high-testosterone people, because high testosterone is associated with a desire to dominate, suggest the researchers.

Gender Differences

People reward angry men but view angry women as less competent, says Yale psychology professor Victoria Brescoll. (see ref 5) Brescoll and Eric Uhlmann, a Northwestern postdoctoral fellow, conducted three studies that looked at the correlation between perceived competence and anger in men and women. The studies, published in the March, 2008 issue of "Psychological Science", showed that participants of both genders perceived angry actors portraying male applicants as deserving more status, more money and a better job than angry females, except when the actors explained their anger outbursts. For women, explaining their anger paid off. For men, it sometimes hurt them, the researchers report. (see ref 5)