Scarlet letters were popular in Hawthorne’s day, but these days spotting cheaters is not as easy. That’s not to say you have to fly blind in your relationship. There are signs of a cheater hidden in personality types, according to a study on sexual behavior. Men who are risk-takers, have performance anxiety or who are easily sexually aroused are most likely to cheat.

And when it comes to women? Infidelity increases when they’re dissatisfied with their relationship or feel that they don’t have enough sexual chemistry. Ultimately, there is no foolproof way to spotting a cheater—but a little science can help.

MORE: What Makes Us Cheat?