Carriers of a certain genetic variation experience positive and negative emotions more strongly, a new study finds.
The genetic variant is carried by around 50% of Caucasians — although the percentage varies between ethnicities.
The feelings are accompanied by greater activation in regions of the brain linked to emotional processing.
The study may help to explain why some people are particularly susceptible to post-traumatic stress disorder (PTSD).
Professor Rebecca Todd who led the study, said:
"People really do see the world differently.The gene is called ADRA2b and it regulates the neurotransmitter norepinephrine.
For people with this gene variation, the emotionally relevant things in the world stand out much more."
Professor Adam Anderson, another of the study's authors, said:
"Emotions are not only about how we feel about the world, but how our brains influence our perception of it.Stronger emotional reactions may be beneficial in some situations, Professor Todd said:
As our genes influence how we literally see the positive and negative aspects of our world more clearly, we may come to believe the world has more rewards or threats."
"People who have the deletion variant are drawing on an additional network in their brains important for calculating the emotional relevance of things in the world.A great example of someone who probably carried this gene variant was the novelist Marcel Proust, famous for his emotional sensitivity.
In any situation where noticing what's relevant in the environment is important, this gene variation would be a positive."
Professor Todd said:
"He bit into the Madeleine cookie and then wrote seven volumes of memoirs.The study was published in the Journal of Neuroscience (Todd et al., 2015).
He probably was emotionally sensitive too and he was certainly creative.
He's a classic deletion carrier."
Comment: Genes predispose some people to focus on the negative