Relying too heavily on Google can lead you into this common mental trap, says decision-making expert

We've all Googled a question and taken the top link as fact, without digging any more into the credibility of the source.

Relying too heavily on the search engine, though, can feed a common mental trap known as availability bias, says Cynthia Borja, a project leader at The Decision Lab, a think tank where researchers study how people make decisions.

Availability bias is the tendency to think easily accessible information is the most factual information.

But Google's algorithm sometimes shows users unreliable or even misleading news sources. The first result you see isn't necessarily the most accurate one.

"If you are not applying a really critical lens and making sure that you're checking more than one source, all you're doing is getting information that is biased from one perspective," Borja says.

How to avoid availability bias

To curb your availability bias, Borja recommends consulting multiple sources of different types.

"I never find a single page and go for that solution," Borja says. "I find something on a university page then I try to find one from a nonprofit on the same thing."

Say you're searching for tips on how to build muscle fast and come across a study. Be sure to compare its findings with another source and look into who funded the research. Even if you're reading a reputable publication, you should check that the sources they are citing are also legitimate.

You can learn to spot misinformation by practicing something called "lateral reading," Google executive Beth Goldberg told CNBC Make It.

This is where you try to verify information you read online by opening new tabs to consult additional sources and evaluate the credibility of the author, organization, and website that published the information.

″[It's] looking up the funder, looking up the name of the website and where it's from, and really digging in and getting other sources to verify what's in the first tab that you're on," says Goldberg.

And, if you have the time, seek sources outside the internet.

"Books still have value and libraries still exist," Borja says. "There are still ways to find information that maybe doesn't fall prey to the algorithm you have in Google."

Google is a useful tool, but you want it to help inform your thought process, not override it.

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