TUESDAY, May 19, 2009 (HealthDay News) -- Regions of the brain that process pleasurable experiences such as sweet tastes and sexual stimuli are the same ones that determine whether an individual is a "people person," say European researchers.
They used MRI to scan the brains of 41 males who'd completed a questionnaire designed to measure their emotional warmth and sociability. Those who were most social had greater concentrations of grey matter (brain-cell containing tissue) in the orbitofrontal cortex (the outer strip of the brain just above the eyes) and in the ventral striatum (located in the center of the brain).
Previous research has shown that both areas play an important role in processing simple rewards such as sweet tastes or sexual stimuli.
"It's interesting that the degree to which we find social interaction rewarding relates to the structure of our brains in regions that are important for simple biological drives such as foods, sweet liquids and sex. Perhaps this gives us a clue to how complex features like sentimentality and affection evolved from structures that in lower animals originally were only important for basic biological survival processes," research leader Dr. Graham Murray, of the University of Cambridge in England, said in a university news release.
"Sociability and emotional warmth are very complex features of our personality. This research helps us understand at a biological level why people differ in the degrees to which we express those traits," he said. However, Murray noted that this research is "only correlational and cross-sectional" and "cannot prove that brain structure determines personality. It could even be that your personality, through experience, helps in part to determine your brain structure."
The study appears in the European Journal of Neuroscience.
This area of research could help improve understanding of mental health disorders, such as schizophrenia, in which social interaction is a major problem.
"Patients with certain psychiatric conditions often experience difficulties in feeling emotional closeness, and this can have a big impact on their life. It could be that the cause of these difficulties is at least partly due to brain structural features of those disorders," Murray said.
Mental Health America explains personality disorders.