From sky diving,bungee jumping,drag racing,and base jumping, name it and S. Kellur has surely tried it. We''ve all known people like Kellur who would try anything just to get the kind of thrill and excitement that would go down deep to their bones.
Now you may ask why on earth there are people like that, those kind who would not care to put their lives on the edge, always seem inviting and luring death to come forth.
Well, you might be surprise to know that there is a biological underpinning for this thrill -seeking behavior. It has actually been found out that adventure-loving people have a significant genetic difference than their calmer counterparts. This first genetic difference was discovered by Richard Ebstein in his laboratory in Jerusalem, in the D4Dr gene on chromosome 11.This has also been proven by Dean Hamer in his experiments on families, as differences between family members have little to do with the environment or culture.
The difference lies in the number of repeats of the sequence of this D4Dr gene,with some people having two, three or four while others having eight, nine or even twelve.It has been found out that the larger the number of repeats, the more ineffective the person''s dopamine receptor is in capturing dopamine
Dopamine is the brain''s "motivational" neurotransmitter.A person having too little of it suffers a frozen personality, the inability to move and at the extreme Parkinson''s disease. On the other hand, people having too much dopamine are easily bored and frequently seek new adventures.
People with many repeats of the sequence or has a long D4Dr gene has low responsiveness to dopamine, hence, they need more "adventurous" pursuits to get the kind of thrill that people with short D4Dr gene get while reading a book.