Dunbar developed his theory after analysing
the findings of UK brain experiments carried out over a decade ago at the University College of London.
The magnetic resonance imaging (MRI) research looked at the brain activity of 17 volunteers as they were shown pictures of their boyfriends and girlfriends, with whom they were truly, madly and deeply in love.
Dunbar said that when the people gazed at images of their loved ones, the rational parts of their brain were affected by “rose-tinted spectacle syndrome” and their hearts ruled their heads, dulling their critical faculties.
“‘What seems to be happening is that you have subconsciously made up your mind that you are interested in the person and the rational bit of the brain -- the bit that would normally say ‘hang on a minute’ -- gets switched off,” the Daily Telegraph quoted Dunbar as explaining at The Times Cheltenham Science Festival on Friday.
“In a relationship you are in a trade-off between caution and just going for it. There is a view that emotion exists to get you off the fence.
“‘A purely rational organism would sit on the fence all the time to avoid being hurt. But if you don’t engage, you won’t form relationships. If the prefrontal cortex is shut down, that protective and cautious element goes,” he added.
