By Bethann Hromatka, Ph.D.
Oxytocin is Greek for “swift birth,” but this hormone – which helps induce labor and promote lactation – has garnered many other names in the media, from the “cuddle chemical” to the “morality molecule.”
The “pro-social” effects of oxytocin on humans has become the subject of innumerable studies of varied reliability that have investigated impacts on trust, generosity, and empathy. But it’s clear that this hormone, which is released into the bloodstream by the pituitary gland, impacts social bonding.
As oxytocin flows through the blood, it communicates with cells by specifically interacting with the oxytocin receptor – a protein on the surface of cells that catches this hormone as it passes by.
Numerous studies link , a SNP in the oxytocin receptor gene called OXTR, to emotional and social processes.Studies have suggested that people with certain genetic variants in OXTR are more sensitive to stress and have reduced social skills compared to others. A recent study published by Shimon Saphire-Bernstein at UCLA provided evidence that people who carry the A version of are less optimistic and have lower self-esteem. In addition, brain scans have suggested that those with these genetic variants are less responsive to social cues than others as well.
Although not proven, there is also some evidence that people who carry the A version of are at increased risk for autism, a disorder characterized by impaired social interaction and communication. Oxytocin is currently being used experimentally to treat children with autism (read more about this here and here).
A new study conducted by Aleksander Kogan at the University of Toronto suggests that people one of these variants are readily perceived by others as being less prosocial than others.
A prosocial behavior is any voluntary behavior intended to benefit another person, for instance showing empathy. Kogan and colleagues recruited “observers” to view “subjects” listening to their romantic partners talk about going through a tough time. After only 20 seconds of watching, observers determined how pro-social the subject was.
People with these variants individuals were judged to be less pro-social and displayed fewer nonverbal cues – head nods and smiles – compared to others.
The study suggested that the association between and prosociality was stronger for men, but also true for women.
Even though these findings resonate with numerous studies linking to prosocial behavior and empathy, they should be considered as preliminary since the study was carried out with a limited number of participants – 23 to be exact and all of European ethnicity. Some geneticists have suggested that this sample size is simply too small to provide meaningful information, but it can also be argued that a very large sample wasn’t necessary because only a single, well-studied SNP was investigated.
Says Kogan,
“Our study benefits from over a dozen studies that have reported findings very consistent with ours using much larger samples from the same general population – Caucasians in the United States.” He also adds, “We are now attempting much larger replication studies.”