Colour and memory: explained simply

Colour helps memory in some specific ways. People recognise photographs of natural scenes better in colour than in black and white, and they find a coloured target faster in a crowded display. Memory also bends colour: we remember a banana as yellower than it was. The common belief that highlighting or colour-coding notes improves learning has much weaker support.

Photograph of hands holding strawberries, edited to remove red. — Photo: cmglee, Photo courtesy of USDA Natural Resources Conservation Service., CC BY-SA 4.0, via Wikimedia Commons

Where colour helps

In experiments, people shown a set of photographs and tested later recognise them a few per cent more accurately when the pictures are in colour, provided the colours are natural. Falsely coloured scenes lose the advantage. Colour helps the visual system separate objects from their background and gives memory an extra feature to store. It also guides attention. An item that differs in colour from everything around it is found almost at once, however many other items there are. Signs, maps and control panels rely on this.

Memory colours

Familiar things have a colour we expect: grass is green, a ripe banana yellow, a post box in India or Britain red. These are called memory colours. Experiments show they tug at perception. Asked to adjust a picture of a banana until it looks grey, people tend to push it slightly towards blue, as if cancelling a yellow that is no longer there. People also remember colours as more saturated than they were. Photographers and film makers know that grass, sky and skin must match the remembered version, not the measured one.

Colour in study

A 2013 review of colour and memory, written by researchers in Malaysia, found many studies reporting benefits for attention and recall, and noted how inconsistent their methods were. A large review of study techniques published the same year by American psychologists rated highlighting as of low usefulness: marking text in colour feels productive but does little unless it goes with harder work such as self-testing. Colour-coding can help organise material, for example one colour per topic. It works by making structure visible, and too many colours undo the benefit.

Sources and further reading

About this page

Original text by the Rang desk, written with AI assistance and checked against the sources above. Meanings of colour vary from place to place and person to person. If we have something wrong, tell us.