The moment when Dorothy passes out in monochrome Kansas and awakes in Technicolor Oz may have been more significant than you’d ever imagined. A new study reveals that children exposed to black-and-white film and TV are more likely to dream in greyscale throughout their life.

Opinions have been divided on the colour of dreams for almost a century. Studies from 1915 through to the 1950s suggested that the vast majority of dreams are in black and white. But the tides turned in the 60s, and later results suggested that up to 83% of dreams contain some colour.

Since this period also marked the transition between black-and-white film and TV and widespread Technicolor, an obvious explanation was that the media had been priming the subjects’ dreams, but differences between the studies prevented the researchers from drawing any firm conclusions.

Whereas the later studies asked subjects to complete dream diaries as soon as they awoke, the earlier research used questionnaires completed in the middle of the day, so the subjects may have simply forgotten colour elements to their dreams and assumed they were greyscale.


Different generations

To lay the debate to rest, Eva Murzyn from the University of Dundee, UK, has incorporated both methods into one study.

She first asked 60 subjects – half of whom were under 25 and half of whom were over 55 – to answer a questionnaire on the colour of their dreams and their childhood exposure to film and TV. The subjects then recorded different aspects of their dreams in a diary every morning.

Murzyn found there was no significant difference between results drawn from the questionnaires and the dream diaries – suggesting that the previous studies were comparable.

She then analysed her own data to find out whether an early exposure to black-and-white TV could still have a lasting effect on her subjects dreams, 40 years later.

Imprinted minds

Only 4.4% of the under-25s’ dreams were black and white. The over-55s who’d had access to colour TV and film during their childhood also reported a very low proportion of just 7.3%.

But the over-55s who had only had access to black-and-white media reported dreaming in black and white roughly a quarter of the time.

“There could be a critical period in our childhood when watching films has a big impact on the way dreams are formed,” she says.

Even though they would have spent only a few hours a day watching TV or films, their attention and emotional engagement would have been heightened during this time, leaving a deeper imprint on their mind.

However, Murzyn concedes it’s still impossible to verify whether the dreams are actually in black-and-white, or whether media exposure somehow alters the way the mind reconstructs the dreams once we wake.

Journal reference: Consciousness and Cognition (DOI: 10.1016/j.concog.2008.09.002)

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