People are genetically predisposed to their sensitivity, finds a new study published in The Journal of Neuroscience.

Rebecca Todd, who led the study, is a professor of psychology at the University of British Columbia; her prior research found people with the gene variant ADRA2B perceived “positive and negative images more vividly.” ADRA2B influences the neurotransmitter norepinephrine — and it appears in “varying degrees across different ethnicities.” While participants who had the variant paid greater attention to negative words in Todd’s first study, the present study focuses more on how the variant affects the brain.  

Todd and her team scanned the brains of 39 participants, 21 of whom carried the genetic variant, as they estimated the amount of  “noise” applied to images containing either positive, negative, or neutral emotional content. When compared to participants without the variant, those with it estimated lower levels of noise on positive and negative images, which is an indicator of “emotional vividness.” These participants also showed significantly more activity in the amygdala, the brain region responsible for emotional regulation, as well as evaluating pleasure and threat.

"We thought, from our previous research, that people with the deletion variant would probably show this emotionally enhanced vividness, and they did more than we would even have predicted," Todd said in a press release.

Todd added these findings may explain why some people are more susceptible to mental health problems, like post-traumatic stress disorder and any intrusive memories following trauma. Ultimately, the variant is an emotional enhancement; it changes the way people see the world.

"Emotions are not only about how we feel about the world, but how our brains influence our perception of it," Adam Anderson, study co-author and professor of human development at Cornell University, said in a press release. "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."

Researchers refer readers to French novel Marcel Proust; “he bit into the Madeline cookie ad, then wrote seven volumes of memoirs,” they explain. To Todd, this suggests he was “probably emotionally sensitive…and certainly creative.” Proust may very well have had this genetic variation.

Source: Todd R, et al. Neurogenetic Variations in Norepinephrine Availability Enhance Perceptual Vividness. Journal of Neuroscience. 2015.