When you start dating a new girl, gain her trust early. Making a good first impression leaves you more wiggle room for messing things up later on in the relationship, according to a new study from the University of California. The research suggests that your likelihood of regaining her trust is directly related to the experiences that led up to a critical moment—say, a big fight.

The study involved an online game where each subject received $8. The subjects could keep the money or give it to an anonymous partner. That "partner" was actually a computer that was programmed to sometimes betray the subject early in the game and sometimes later (either way, it was before the subject chose to give the money away or not). Researchers found that if the subject was betrayed early on, he or she would be more likely to keep the money, compared with when the partner committed betrayal much later.

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While this may all sound like psychological mumbo-jumbo, it's a pretty simple concept: Betraying somebody early in a relationship activates parts of the brain that deal with planning, learning, problem solving, and feelings of uncertainty. Quite a dangerous mix to mess with if you're hoping to ever be trusted again. 

While it's easier to regain trust in a long-term relationship, we wouldn't recommend firing lies at your steady girlfriend. Still, if you do mess up, here's how to master an artful apology.