As (in)conspicuous as possible

Some colours have a special meaning. So does the colour red. Red is vital for animals and humans. That's what scientists say. Research results show that red can enhance the effect of external stimuli, both in a pleasant and repulsive way. They show that red increases the attractiveness of women and men, but also intensifies the effect of negative stimuli. Depending on the context, red can serve as an appetite signal or as a warning signal, e.g. in the animal and plant world for defence or inedibility.

But does colour also influence our memory? Evolutionary considerations and recent research in psychology suggest that the colour red also functions as a signal for the meaning of an object. However, there is no scientific evidence that this signalling function of the colour red also influences human memory, the ability to remember, that it is memorised.

Is red better remembered? This was previously assumed because red as a signal colour increases attention. Scientists believe that attention is one of the most important prerequisites for retaining features in the representation of objects. If I look at something attentively, I can also remember it better.

And another question: What is the object retention of a colour? Are objects and their properties, such as colour, perceived as an inseparable unit? Does red increase the information content of objects? A better subsequent memory of the objects would be a sure indication of this.

For us brand designers, the question is: How does the memorability of signs and objects change due to their colour? Are red logos easier to remember than blue logos? Memorability and recall value are important criteria for the quality of a brand design.

The aim of this study was to investigate whether the colour red also influences human memory. If red serves as a signal for the importance of an object, then the subsequent memory of an object could also be improved if the object is coloured red.

Based on the hypothesis that words or objects coloured red or orange are easier to remember, a team from the Institute of Psychology at the University of Regensburg, led by Prof. Dr Christof Kuhbandner, investigated the influence of object colour on subsequent memory.

In several experiments, test subjects were shown objects in the primary colours red, green, blue and yellow. The researchers then analysed how well the participants were able to remember the various objects and their colours. During the experiments, they varied the type of objects (words or pictures), the complexity of the objects (one object or several objects) and the type of learning (conscious or unconscious learning).

The colours red, blue, yellow and green were chosen because they represent psychological primary colours and belong to the limited number of primary colours that can be clearly identified in different cultures.

As it turned out after four individual studies, the swing in favour of red was not significant enough. Whether red, orange, green, yellow or blue - the colour had no influence on whether the test subjects remembered the word or object at all. However, as the reader may have guessed, the reverse was true. Although the colour had no measurable influence on the general memory of the mere presence of certain objects, it did influence the memory of the colour of the objects themselves. On average, the test subjects were better able to remember the colour of an object when it was presented in red or orange. It was now clear to the scientists that objects and their properties, such as colour, are not always treated as an indivisible construct. The experiments also showed that the colour influenced the subjects' subjective judgement of their own colour memories. For red objects in particular, the subjects made reliable judgements about the accuracy of their colour memories, while they were rather unreliable for green objects.