Dr. Phil McGraw, American television personality and author known for relationship advice, spouted more of his wisdom on April 26 during a morning show interview where he explained a cheater can be identified through physical signs and genetic testing.
"Obviously a lot of this is learned, a lot of it's social. Probably 70 percent, something like that, but there are things in our makeup that make us at high-risk for this," said McGraw, a former psychologist.
McGraw was basing his discourse on a body of research that essentially shows that if a man has low oxytocin (a bonding hormone), high testerone (identified by a longer ring finger compared to index finger), and even the presence of a gene, allele 334, he runs the risk of being unfaithful.
Before you begin asking every guy you date to undergo brain scans, genetic tests and sizing up their pointers and ring fingers - it is important to understand that a longer ring finger is associated with greater uptake in testosterone in utero and oxytocin can also be a factor in parental bonds, often termed the "love hormone."
"How your brain is configured, how it's wired, can be a huge contributing factor," continued McGraw. "You find these people that have a history of cheating, you compare their brains to normal and you see it's dramatically different."
"The front of our brain is higher reasoning, and it's where we have the inhibition sensors, where we put the brakes on impulsive behavior. And if it's very low activity, then you get very high impulse. So what we're talking about here is: Who is at risk? And these folks are risk-takers. And you often see traumatic brain injury. That contributes to the likelihood to be cheater."
However, being wired to be unfaithful doesn't excuse the act and it is unclear if physicians will start screening potential mates before commitment ceremonies since the research is inconclusive that any of these traits definitively makes cheater.
To watch McGraw's full segment and see images of brain activity of a chronic cheater, go to: http://www.cbsnews.com/video/watch/?id=6433074n&tag=api
For more information on allele 334, see "Gene Associated with Social Behavior in Animals Has Similar Effects in Human Males":
Learn more about oxytocin: http://www.oxytocin.org and http://psychiatry.jwatch.org/cgi/content/citation/2010/412/3
Full study, "Photocopies yield lower digit ratios (2D:4D) than direct finger measurements": http://www.ncbi.nlm.nih.gov/pubmed/15971015