April 8, 2018 - No Comments!

What does green Coca Cola teach us about the Stroop Effect?

If I said ‘Coca-Cola’ what colour immediately comes to mind?

The highly iconic Coca-Cola red.

In 2013 Coca-Cola introduced their new Coca-Cola Life range, a brand using only green. This gives an interesting opportunity to observe a globally recognised brand and colour association and turn it on its head.
In effect, creating the Stroop Effect on a mass scale.

Ever seen a red blue yellow blue Stroop test?

The confusion between the written colour and the perceived colour is named The Stroop Effect. It is due to the brain’s ‘speed of processing’. Meaning that words are processed quicker than perceptual processing like colour. The same can be applied to emotional responses, the Emotional Stroop Effect and Spatial and Numerical.

What are the main effects of the Stroop Effect?

Latency of reaction

Keller’s study into the ‘Food Stroop Effect’ found something alarming. The higher a person’s BMI, the longer it took to recognise a food when the label and food didn’t match1. For example, when Haribo's logo was stamped on a broccoli, it took people longer to recognise it wasn't from the brand and it was in fact, a healthy food. Not only does this highlight the huge cognitive bias’ of established brands on our preferences and buying habits2, but that changing them literally takes people longer to process them. Disruptors in the marketing world can help brands by making their products more salient, on the other hand, the disassociation may be off-putting by disrupting a consumers trust of the brand or product.

Power play

By slowing down people’s responses to marketing words, it increases their impact. In these cases, applying the Stroop Effect to ‘power words’ in campaigns can increase their impact. Mr Muscle’s hero parody advertising campaign shows the Perceptual Stroop Effect at its best. Overlaying Muscle over a slight man introduces a disruptor than strengthens the brand.

Mr Muscle 'Loves the jobs you hate campaign"

Dissolution of brand

Up until this point, Coca-Cola was always red, their entire brand narrative has red stamped all over it. From cans, lorries and digital media. To introduce a green only product has the potential to dilute the strong narrative, and weaken the dominance of their main brand colour.

Without pulling up the Coca-Cola sales reports, it’s difficult to conclude whether their red-green shift paid off. Manipulating people’s latency of reactions and cognitive bias’ can work is implemented correctly.




  1. Keller, K. Kuilema, L. Lee, N. Yoon, J. Mascaro, B. Combes, A. Deutsch, B. Sorte, K. Halford, J. The impact of food branding on children’s eating behavior and obesity. 2012 
  2. Black, K. Parks, S. A brand loyalty model involving cognitive, affective, and conative brand loyalty and customer satisfaction 2003 

Image credit: Mike Mozart, under Creative CC license

Published by: Dura in Design psychology

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