A User Experience – actually every experience we have – is a construct of our mind, our cognition. It has more to do with our inner than with the outer world or what we commonly call «reality».
This may sound rather unusual to some people. But that is only because many of us rarely think about the processes of perception and processing that are constantly going on inside of us. Very few people think about what happens in our brains when we meet a new person, read something, or use a website.
The Constructed Reality
First, we should be aware that not all of the information that our senses receive is processed. It is estimated that we receive about 11 million bits of information per second through our senses, but we can only process about 40 bits of information per second*1. So a lot of information is initially “filtered out”. Our brain makes this selection very quickly, without our awareness – this is called «preattentive processing».
The remaining pieces of information that are selected for further processing are also not “consciously” available to us. They are first heavily adapted before they are transported into our consciousness, enriched with prior knowledge and hypothetical assumptions.
What we think we perceive objectively is the product of highly complex processing operations of our brain.
Similar to how an application like ChatGPT presents us with a pretty simple user interface while highly complex processes are running in the background, human consciousness provides us with a «user-centered» reality that represents only a tiny fraction of the information that surrounds us and is only a small reflection of what our brain actually processes and stores.
In addition, our cognitive processing has some peculiarities due to the way our brains are structured. This is partly because our brains have to be extremely flexible, because apparently no one knew exactly what skills humans would eventually need. Our ability to read is a good example of this – it is a very recent invention in evolutionary history. However, our brain is so flexible that it can not only learn to read, but also to do other, completely unfamiliar things. It can even restructure itself to perform repetitive tasks faster, more efficiently, and most importantly, more intuitively. This amazing ability is called «Neuroplasticity».
For example, in the case of blind people, areas of the brain that are actually responsible for processing visual stimuli are freed up and used for other abilities. Thus, blind people have a more sensitive sense of touch and hearing than seeing people. They can also process spoken language much more quickly. Anyone who has seen a blind person use a screen reader knows what I am talking about.
Selective perception and cognitive biases
Due to our limited processing capacity in the face of information overload, our brains are forced to perform many processes as simply and efficiently as possible. It prefers familiar solutions, simplifies complex structures and facts, and likes to take shortcuts when solving problems*2. This leads, however, to difficulties in certain situations. In many cases, so-called biases occur, i.e. deviations between the objectively expected result and the result of our subjective processing.
Some of these biases are so pervasive that our normative expectations have adapted to these misinterpretations. There are hundreds of examples of this in perceptual and cognitive science that have been demonstrated in numerous studies.
I would like to give just two examples here. For those who are interested in this topic, I have an interesting link at the end of this post.
1. Optical Center
The «Optical Center effect» describes a bias in the way we judge objects. When asked to determine the exact vertical center of an object, almost all of us tend to define it about two to three percent higher than it actually is geometrically or mathematically. We have become so accustomed to this bias that positioning slightly above the geometric center seems more harmonious and natural to us than the exact geometric center, and we prefer it.
Sometimes unconsciously, but also consciously, we use the optical center in design or interior decoration. For example, pictures in a frame or text on a book page are usually vertically positioned higher than their geometric center. The center lines of our letters are all at the optical center. If they were in the geometric center, they would feel “out of place” – in other words, they would appear disharmonic to us.
The causes of this bias are not fully explored scientifically. It is probably a combination of our brain’s drive for efficiency and early childhood conditioning.
Striving for Efficiency
As mentioned above, our brain’s striving for efficiency is mainly based on the limitation of our cognitive abilities. For this reason, the optimal solution to many problems is too time-consuming and resource-intensive. To solve these problems, our cognition falls back on simplifying decision strategies (so-called heuristics) or already existing solutions and results in order to arrive as quickly as possible at a good, but not necessarily exact or optimal solution. This is also the case when judging the center of an object.
Conditioning
Conditioning is based on the fact that, from an early age, our brains have a lot to do with interpreting meta-information conveyed to us through facial expressions. In our interpersonal communication, it is extremely important to recognize the mood of the person with whom we are interacting on an ad hoc basis. Facial expressions occur almost exclusively in the lower part of the face – that is, we focus on the mouth, nose, and eyes – while the upper part of the head (forehead, hair) is perceived only peripherally. It is filtered out and tends to receive less attention. This leads to an overemphasis and overvaluation of the lower half of the face.
We tend to undervalue the upper part of the head, especially the hair, because facial expressions mainly occur in the lower half of the head.
The overemphasis or exaggeration of the lower part of the face is so ubiquitous that when you ask people (who are not professional illustrators, artists or photographers) to draw a face, they usually place the eyes much too high*3. Anatomically correct, the eyes are almost exactly in the middle of the head.
The illustration shows a drawing by an adult who was asked to draw himself. More than 95% of people who have not received any drawing training position the eyes much too high on the head.
As already mentioned, interpreting faces is so important to us that the principle of exaggerating the lower half of the face is also transferred to other areas on a quasi-universal basis. The technical term for this is «Selective Availability». It describes the fact that our brain makes certain results, concepts and approaches that we have frequently and successfully applied more readily available. As an implication, these patterns or information are applied more oftenin our cognitive processes than we sometimes like – even in tasks or problem solving that have absolutely nothing to do with the original task. This is also the direction of our second example:
2. Anchoring effect
The «Anchoring effect» describes the tendency of people to be strongly influenced in their judgments or decisions by the context or by a piece of information that is immediately available – the so-called anchor – even if this anchor has nothing to do with the actual question.
In a study by Tversky and Kahneman*4, subjects were asked to spin a wheel of fortune. The wheel gave them a number between 0 and 100. The subjects were then asked to estimate what percentage of the members of the United Nations were African countries. The results were astonishing because the anchors obtained from spinning the wheel significantly influenced the estimates. The average of all estimates was 45%. However, the mean of the estimates of people who had previously spun a number of 10 or less on the wheel of chance was only 25%.
In the famous «Anchoring Experiment», Tversky and Kahneman showed how subjects are unconsciously influenced by a seemingly random number when they have to answer an estimation question.
How does this bias arise?
The so-called anchoring task (spinning the wheel of chance and getting a random number) activates memory content that matches the anchor number and makes it available in easily retrievable areas of our memory for subsequent tasks. The information in these areas is then used preferentially, even in tasks that have nothing to do with the original task.
Practical Significance
What we experience and believe we know is a product of our cognition and, unfortunately, of deliberately employed deception.
The mere fact that we are informed more frequently or more emotionally about certain issues or claims through the ubiquitous media means that we weight and evaluate them differently than issues about which we are rarely informed. This can lead us to grossly overestimate certain risks simply because the media reports on them more frequently.
For example, the vast majority of people rate the risk of being attacked by a shark as significantly higher than the risk of being killed by a falling coconut*5. However, the probability is exactly the opposite. But we tend to be more aware of shark accidents, and shark attacks are probably more frequently reported in the media than beachgoers killed by falling coconuts.
Anchors can also play a critical role in negotiation situations. For example, the subjective perception of loss or gain depends heavily on the initial offer, which can significantly influence the negotiation process. Sellers and online shops like to offer products at a high price and then reduce the price significantly, giving the impression that the price is now extremely low.
Even experts are not completely immune to the anchoring effect. Studies*6 show that judges, experts and juries have been massively manipulated by it in the past. In this context, there are other methods that are sometimes consciously or unconsciously used to influence us in one direction or another, such as
These principles do not necessarily have to be used to our disadvantage. When applied correctly, they can even make a decisive contribution to high usability and exceptional User Experience.
A UX/UI designer who knows that our short-term memory is limited or that they can overwhelm a user if they provide them with too many options (see Hick’s Law) can significantly improve usability, if not the entire user experience, through the application of cognitive principles. It is therefore very important to know the cognitive principles necessary for this.
That’s why I’ve spent the last few months putting together the most comprehensive overview possible of the cognitive principles that play a major role in a good user experience, and I’m pleased to present it here:
cognitive-ux.com
The website currently includes the 72 most important cognitive principles that can play a role in a User Experience. There is a search function, a filter option and the possibility to create a favorites list. Every week, I will introduce a law or principle in more detail on my LinkedIn page, accompanied by concrete examples of how it can be applied.
References:
*1: Tor Nørretranders (1998): The User Illusion: Cutting Consciousness Down to Size. The ratio of 10 million to 40 bit/s was determined by Tor Nørretranders Because the methods of data collection (e.g. the summing up of the modalities of perception and the conversion into “bit/s”) are subject to numerous assumptions, the values are to be considered as guidelines. However, studies show that conscious perception encompasses only a fraction of the stimuli received by the brain.
*2: Herbert A. Simon (1956): Rational choice and the structure of the environment. In: Psychological Review, pp. 129–138; doi:10.1037/h0042769. Herbert A. Simon explains that people are limited in their cognitive performance by various factors when processing information. These factors include insufficient information, limited time, limited attention and limited cognitive resources. People therefore do not always choose the most optimal solution, but rather the first acceptable solution in view of these limited resources.
*3: Betty Edwards (1979): Drawing on the Right Side of the Brain. Los Angeles: J. P. Tarcher. This standard work on drawing explains how beginners distort certain facial proportions when drawing a portrait. Among other things, Edwards cites the frequent placement of the eyes too far up as a typical pattern that results from our mental conception of a face.
*4: Tversky, A. & Kahneman, D. (1974): Judgment under Uncertainty: Heuristics and Biases. Science, 185(4157), 1124–1131, https://www.science.org/doi/10.1126/science.185.4157.1124
*5: The fact that we overestimate the risk of a shark attack is due to the so-called Availability Heuristic. Drastic and media-effective dangers (such as shark attacks) imprint themselves better on our memory than more everyday dangers.
*6: Englich, B., Mussweiler, T., & Strack, F. (2006): Playing Dice With Criminal Sentences: The Influence of Irrelevant Anchors on Experts. Personality and Social Psychology Bulletin, 32(2), 188–200, https://doi.org/10.1177/0146167205282152
Further information:
Alessandra Rodrigues Eismann (2023): Cognitive Bias in UX Research, https://www.centigrade.de/de/blog/cognitive-bias-im-ux-research-ein-survival-guide/
Charlotte Ruhl, Harvard University (2023): Cognitive Bias: How We Are Wired to Misjudge, https://www.simplypsychology.org/cognitive-bias.html