Sunday, April 12, 2009

Personality decided at birth, say scientists

Pessimism and shyness is one of four categories scientists investigated. Photo / Bay of Plenty TimesBy Steve Connor

image: Pessimism and shyness is one of four categories scientists investigated.

Personality types are linked with structural differences in the brain - which could explain why one child grows up to be impulsive and outgoing while another becomes diligent and introspective.

Anatomical differences between the brains of 85 people have been measured and linked with the four main categories of personality types as defined by psychiatrists using a clinically recognised system of character evaluation.

The researchers said the brain differences are structural and can be measured as variations in the size of specific regions of the brain that appear to be linked with each of the four personality types.

Brain scans that measure differences in volume down to an accuracy of less than one cubic millimetre found, for instance, that people defined as novelty-seeking personalities had a structurally bigger area of the brain above the eye sockets, known as the inferior part of the frontal lobe.

People with smaller volumes of tissue in this region displayed higher levels of timidity, approval-seeking behaviours and a greater tendency to seek gratification from external sources such as food or drugs, said Professor Annalena Venneri of the University of Hull.

People with "harm-avoidance" personalities had significantly smaller volumes of tissue in brain regions called the orbito-frontal area and the posterior occipital region, compared with other personality types.

"Reward-dependence" personalities stood out for having smaller volumes of tissue in the fronto-striatal and limbic areas of the brain.

If the findings are confirmed by other scientists, they suggest that children are not only born with a given personality type, but they develop anatomically different brains as a result of being that sort of person. It raises the prospect of being able to test a young child's future personality by viewing the anatomy of their brain with a hospital scanner.

"This study shows that personality traits are something you are born with, but their full expression can be modulated during development with the right approach," said Professor Venneri, who carried out the study with colleagues from the University of Parma in Italy and Washington University in St Louis.

The four personality types were classified as "novelty seeking" - characterised by impulsive actions;  "harm avoidance" - marked by pessimism and shyness; "reward dependence" - with an addictive personality; and "persistence" - who are people who tend to be industrious, hard-working and perfectionist. ...

via Personality decided at birth, say scientists - Health - NZ Herald News.

What size is your brain if you are a persistent novelty seeker who avoids harm and likes rewards? That's me.

1 comment:

James said...

An interesting read. As our understanding of the brain and genetics increases more and more it seems to slowly erode our painfully primitive ideas of each individual and personality being truly unique (and seems to erode even more the idea of each person having a "soul" that is just as "unique" as they are). Of course we all have our quirks, but one day perhaps even those quirks will be explained? Actually psychology may be able to explain the quirks already, I just mean when neurology finally buys up that intellectual real estate as well.

Just think of the day when we can alter our own genetic code.