However, nowadays researchers are looking for better ways to spot liars.

One of the most promising areas of research is cognitive loading.

The idea is that lying requires more cognitive effort than telling the truth.

You have to constantly monitor yourself and make sure your story doesn't contradict itself.

Therefore, if you increase the cognitive load on a person by just the right amount,

you 'll get to a point where the liar can't handle the extra stress, while the truth teller can.

For example, one experiment tried to do this by getting participants

to tell their stories backwards.

This led to a 20 % improvement in lie detection accuracy.

Another experiment did this by asking unexpected questions

and got accuracy rates up to 80 %.

However, this area of research is still young.

We should be careful not to herald these as the new psychological tricks,

until more research comes out.

Otherwise, don't rely too heavily on body language the next time you 're trying to spot a liar.