To lift your mood, just think blue

Are you aware of the colours surrounding you right now? Take a moment to notice, because they’re having an effect on your mood.

Francis Adams and Charles Osgood at the University of Illinois looked at 89 studies across 23 cultures and found almost universal reactions when individuals were shown different colours. Black and grey suggested passivity and negativity; red was seen as strong and associated with increased activity; and blue generated positive feelings and a sense of calm.

Personal history and your own culture exert an influence – for example, in the West, white is associated with cleanliness and purity, whereas in some Eastern cultures it connotes mourning.

The colour spectrum (excluding black and white) is divided into two main groups. “Warm” colours – reds, yellows and orange – are associated with excitement and increased energy, and when the shade is intense, with anger, hostility and even the desire to dominate. “Cool” colours – blues, greens and purples, particularly paler variations – make us feel soothed, calm and more relaxed.

Psychologists have long been interested in the differential effects of warm and cool colours. Andrew Elliot at the University of Rochester measured the strength of participants’ hand grip when exposed to red, grey or blue. Exposure to red increased the force and velocity of motor output. In another experiment, he assigned undergraduates a number written in red, green or black ink just before asking them to complete a written test. Those who’d been given a red number scored 20 per cent lower than those with numbers written in green or black ink.

Ravi Mehta and Rui Zhu at the University of British Columbia exposed participants to red or blue lighting and measured their performance on different cognitive tasks.

Participants excelled on creative tasks under the blue condition, and scored more highly on detailed tasks when in red lighting.

Keith Jacobs and James Suess at Loyola University in New Orleans put undergraduates in rooms with red, yellow, green or blue light for 15 minutes and assessed their anxiety levels at five-minute intervals. Those exposed to red and yellow had significantly higher levels of anxiety.

Even the colour of the pills we take can influence the expectations we have about how they’ll affect us. Anton de Craen at the University of Amsterdam amalgamated the results of 12 studies assessing 49 different medications. Overall, participants assumed red, yellow and orange pills would energise them, whereas blue, green and white pills were seen as tranquillising.

Colour also affects spending. Joseph Bellizzi and Robert Hite at Arizona and Kansas state universities created simulated shopping environments in predominantly red or blue colours. Participants were more inclined to make more purchases in the blue environments.

Is this what they call blue-sky thinking?