Can Aggression Be Linked To Low Serotonin Levels?

Low levels of the neurotransmitter serotonin have been linked for some time with a range of conditions including depression, anxiety, obsessive-compulsive disorder, impulsive behavior and alcoholism, but more recently it has been suggested that low serotonin may also play a key role in aggression.

Put simply, the hypothesis is that aggressive behavior is often linked to impulsive tendencies, eg criminal acts where the impulse for violence is not countermanded by fears of reprisal or the threat of punishment. Depleted serotonin levels have been put forward as the biological basis for impulsive behavior patterns, and there is some evidence to support this - low serotonin has been linked to unprovoked aggressive behavior towards others, type II alcoholism, and greater risk-taking and aggression in non-human primates.

Low Tryptophan Diet Further support for this argument was provided at the 25th Annual Meeting of the American Society for Neuroscience last month, in the form of a study conducted by researchers at the University of Texas. Frederick Moeller and colleagues found that normal healthy males exhibited a significant increase in aggressive behavior when given a diet low in the essential amino acid tryptophan, a precursor molecule for serotonin.