Researchers have found the first physiological evidence that invisible subliminal images do attract the brain's attention on a subconscious level. The wider implications is that techniques such as subliminal advertising, now banned in the UK but still legal in the USA, certainly do leave their mark on the brain.
Using fMRI the study looked at whether an image you aren't aware of, but one which reaches the retina -- has an impact on brain activity in the primary visual cortex, part of the occipital lobe.
Subjects were found to respond to the object even when they were not consciously aware of having seen the object.
What's interesting here is that your brain does log things that you aren't even aware of and can't ever become aware of. It shows there is a brain response in the primary visual cortex to subliminal images that attract our attention -- without us having the impression of having seen anything. These findings point to the sort of impact that subliminal advertising may have on the brain. What our study doesn't address is whether this would then influence you to go out and buy a product. It's likely that subliminal advertising may affect our decisions "
