Adverts 'can implant false memories'

This has been demonstrated by psychologists who managed to fool volunteers into believing they had shaken hands with Bugs Bunny at Disney World in Florida. No such Disney character exists.

It was done by showing the guinea pigs a concocted advert in which Disney World visitors are seen to greet the cartoon character - the volunteers became convinced they must have done the same as a child.

Professor Elizabeth Loftus at the University of Washington in Seattle, US, said of the research: "We found that autobiographically-focused advertising can make events (even impossible ones) seem more likely to have happened to them as children."

Professor Loftus talked about her team's work at the British Association's Festival of Science in Glasgow.

She said people ought to be aware of the extent to which advertising messages could influence their thinking.

She quoted the case of a root beer manufacturer which discovered its adult customers had memories of drinking the product from bottles. These had to be false memories, she said, because the root beer had only been sold in bottles in the last 10 years.

Prior to that, it was only available from soda fountains. Professor Loftus said slogans on the bottle such as "original", "old fashioned" and "since 1924" had clearly conjured up images of times gone by.