Are you bad at spotting a lie?

New research by Dr. Leanne ten Brinke, a forensic psychologist at the Haas School of Business at the University of California, Berkeley, and her collaborators, suggests that our instincts for judging liars are actually fairly strong — but our conscious minds sometimes fail us.

Luckily, there are signs we can look for when trying to detect a lie.

Dr. Lillian Glass, a behavioral analyst and body language expert who has worked with the FBI on unmasking signals of deception, says when trying to figure out if someone is lying, you first need to understand how the person normally acts. Then you'll want to pay careful attention to their facial expressions, body language, and speech patterns, she writes in her book "The Body Language of Liars."

1. They change their head position quickly.

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If you see someone suddenly make a head movement when you ask them a direct question, they may be lying to you about something.

"The head will be retracted or jerked back, bowed down, or cocked or tilted to the side," writes Glass. This will often happen right before the person is expected to respond to a question.

2. Their breathing changes.

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When someone is lying to you, they may begin to breathe heavily, Glass says. "It's a reflex action."

When their breathing changes, their shoulders will rise and their voice may get shallow, she adds. “In essence, they are out of breath because their heart rate and blood flow change. You body experiences these types of changes when you’re nervous and feeling tense — when you lie.”

3. They stand very still.

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