Subliminal images are out of sight, not out of mind

NEW YORK (Reuters Life!) - When it comes to subliminal images, out of sight is not out of mind.

Although the pictures or messages are invisible and people are not aware of having seen them, they grab the brain's attention on a subconscious level, researchers said.

The findings by scientists at University College London suggest that subliminal advertising, which uses images or message to influence consumers, leaves a mark on the brain.

"It is the first time that it is shown that the brain can pay attention to things that we never became aware of," said Dr Bahado Bahrami, the head of the team, said in an interview.

The researchers used a scanning technique called functional MRI to record activity in the brains of volunteers who were shown images and asked to perform tasks.

They discovered that the brain responds to faint images, even though the viewer was not consciously aware of having seen it.

"What is interesting here is that your brain does log things that you aren't even aware of and can't ever become aware of," Bahrami explained.

"These findings point to the sort of impact that subliminal advertising may have on the brain."

But Bahrami said the study does not reveal whether or not it affects a person's decision to buy a product.

The scientists asked volunteers to wear red and blue filtered glasses and presented a faint image of everyday objects to one eye and a strong continuous flashing image to the other. The stronger image completely suppressed the fainter one.

The volunteers were also asked to perform simple and more difficult mental tasks at the same time.

During the easier tasks the brains in the volunteers picked up the subliminal stimulus but in the harder tasks the scans did not record any brain activity because the brain blocked out the subliminal image.

"What we have shown is that we can get reliable responses from the visual cortex (of the brain) that correspond to the faint images although the subjects don't see them," said Bahrami.

"Those responses are reduced when the subjects are busy doing something difficult, which means that they are filtered out and the subjects don't pay attention to them," he added.