Art lovers looking at a painting they think is fake have an entirely different response from those who think it is genuine, say researchers.
Brain scans revealed how much the enjoyment of art is influenced by the information given to the viewer.
The pleasure revealed in brain activity depended on the viewer believing that a Rembrandt painting was authentic.
Professor Martin Kemp of Oxford University says it shows "the way we view art is not rational".
The pretension-puncturing experiment suggests that the appreciation of art is strongly linked to the accompanying information - rather than an objective judgement.
The pleasure taken from a masterpiece is shaped by the viewer being told by others that this is an authentic work.
Faking itThe study scanned the brains of people as they viewed images of Rembrandt portraits - some authentic and others which were imitations and fakes.
Rembrandt was chosen as a good example because recent scholarship has been trying to identify imitations and copies of the Dutch painter's work.
“Start QuoteEven when we cannot distinguish between two works, the knowledge that one was painted by a renowned artist makes us respond to it very differently”
Martin KempProfessor of the History of Art, Oxford UniversityThe experiment in neuroscience and aesthetics compared how the brains reacted to paintings which people thought were authentic with their responses to paintings they were told were fakes.
This found that the responses to viewing an authentic old master were deeply pleasurable, likened to tasting good food or winning a bet.
This warm glow of aesthetic pleasure was absent when the viewers looked at an image they had been told was fake. Instead the brain activity was associated with strategy and planning, as though the subject was trying to work out why this was not an authentic painting.
The study showed the strength of suggestibility in such artistic responses. The beauty was not just in the eye of the holder, but also it seems the copyright holder.
By Sean Coughlan BBC News education correspondent
Brain scans revealed how much the enjoyment of art is influenced by the information given to the viewer.
The pleasure revealed in brain activity depended on the viewer believing that a Rembrandt painting was authentic.
Professor Martin Kemp of Oxford University says it shows "the way we view art is not rational".
The pretension-puncturing experiment suggests that the appreciation of art is strongly linked to the accompanying information - rather than an objective judgement.
The pleasure taken from a masterpiece is shaped by the viewer being told by others that this is an authentic work.
Faking itThe study scanned the brains of people as they viewed images of Rembrandt portraits - some authentic and others which were imitations and fakes.
Rembrandt was chosen as a good example because recent scholarship has been trying to identify imitations and copies of the Dutch painter's work.
“Start QuoteEven when we cannot distinguish between two works, the knowledge that one was painted by a renowned artist makes us respond to it very differently”
Martin KempProfessor of the History of Art, Oxford UniversityThe experiment in neuroscience and aesthetics compared how the brains reacted to paintings which people thought were authentic with their responses to paintings they were told were fakes.
This found that the responses to viewing an authentic old master were deeply pleasurable, likened to tasting good food or winning a bet.
This warm glow of aesthetic pleasure was absent when the viewers looked at an image they had been told was fake. Instead the brain activity was associated with strategy and planning, as though the subject was trying to work out why this was not an authentic painting.
The study showed the strength of suggestibility in such artistic responses. The beauty was not just in the eye of the holder, but also it seems the copyright holder.
By Sean Coughlan BBC News education correspondent