Serotonin Levels Effect To Feelings of Anger

Recommend to others!

The changing levels of serotonin, a neurotransmitter or brain chemical which can either shoot up or decline during hunger or stress, also tend to affect the parts of the brain which respond to anger and regulate the same. This effect has been discovered by scientists from Cambridge University in Britain. The study involved healthy individuals and these people have shown that when their serotonin levels are low, the brain’s ability to regulate the emotional responses to anger.

Previous scientific studies have linked aggression to reduced levels of serotonin. This recent study was able to show how serotonin is able to regulate the brain’s response and also why there are people who are more prone to aggression. According to researchers, they are hoping that their study will be able to pave the way in developing new treatments for psychiatric disorders, where aggression and violent behavior are common signs and symptoms.

The study, which was also published in the journal Biological Psychiatry, engaged healthy volunteers whose serotonin levels were altered through tweaking their diet. On the date that their serotonin levels were depleted, they were also given a combination of amino acids which lack tryptophan. Tryptophan is a type of protein considered as the building block of serotonin. On a separate day, they were also given a placebo drug which contained the same mixture plus a normal amount of serotonin.

Using fMRI or functional Magnetic Resonance Imaging, the scientists scanned the brains of the persons while they were presented with faces showing angry, sad and neutral facial expressions. Using the fMRI, they were able to differentiate the reaction of the brain as they viewed angry faces and sad or neutral faces.

The results of the study was able to show that “low brain serotonin made communications between specific brain regions of the emotional limbic system of the brain — a structure called the amygdala — and the frontal lobes weaker compared to when serotonin levels are normal.”

The researchers also made use of a personality questionnaire to identify which among these human volunteers had the propensity to become aggressive. Among these subjects, the relationship connecting the amygdala and the prefrontal cortex was a lot weaker after they were depleted with serotonin levels.

According to Luca Passamonti, who also worked on the research with the help of colleagues at the Cambridge Cognition and Brain Sciences Unit of Medical Research Council, “Although these results came from healthy volunteers, they are also relevant for a broad range of psychiatric disorders.” Furthermore, she said that “For example, patients with an condition known as intermittent explosive disorder (IED) typically can have intense, uncontrollable outbursts of violence which may be triggered by cues such as a facial expression of anger.”

Lastly, Passamonti concluded that, “We are hopeful that our research will lead to improved diagnostics as well as better treatments for this and other conditions.”





  1. The lack of serotonin not only cause depression , anger and other states of mood. But serotonin levels can also change the sexuality of a person. This is confirmed by a recent study on mice. Mice with lack of serotonin became bisexual.

Speak Your Mind


Current day month ye@r *