Ads that circumvent consumers' conscious awareness by depicting a fun, vague or sexy scene that seems to have nothing to do with the product are less likely to activate the part of your brain that inhibits impulse buying, a new study shows.

Advertisements are all around us, and they vary greatly in their attempts to attract consumers. Some ads highlight the product's features, while other ads' content seems to be completely unrelated to the product they're trying to sell. It's the latter type of ads that shoppers need to be most wary of, according to a new study.

Researchers at the University of California, Los Angeles, and George Washington University focused on two different types of advertisements. The first type of ad, called "logical persuasion," or LP, presents facts about the product, such as, "This car gets 42 miles to the gallon." The second type of ad is referred to as "nonrational influence" (NI) because it circumvents consumers' conscious awareness by depicting a fun, vague or sexy scene that seems to have nothing to do with the product.

In the study, researchers showed advertising images to 11 women and 13 men while recording the electrical activity in their brains using electroencephalography (EEG). Each participant viewed 24 ads that had appeared in magazines and newspapers.

The ads contained either LP or NI images. LP ads showed a table of facts and figures in a cigarette ad and suggestions about selecting food for dogs on the basis of their activity level in an ad for pet food. The NI advertisements included a liquor ad featuring an image of beading water and a cigarette ad showing a woman leapfrogging over a fire hydrant that is spraying water as a man grins behind her.

The researchers found that the brain regions involved in decision-making and emotional processing (including the orbitofrontal and anterior cingulate regions, the amygdala, and the hippocampus) experienced significantly higher activity levels when participants looked at the LP ads. These brain regions have been shown to help inhibit a person's response to certain stimuli, such as preventing an impulse purchase.

When participants viewed the NI advertisements, however, these regions of the brain did not show activity levels that were as high as what the individuals experienced when they viewed the LP ads.

"Watch your brain and watch your wallet," study researcher Ian Cook, a professor of psychiatry at the Semel Institute for Neuroscience and Human Behavior at UCLA, said in a statement. "These results suggest that the lower levels of brain activity from ads employing NI images could lead to less behavioral inhibition, which could translate to less restraint when it comes to buying products depicted in the NI advertisements."

The study is published in the current edition of the Journal of Neuroscience, Psychology, and Economics.

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