How do perceptions influence individual behavior?

How our brain decides for us

Mona Blum reports from the CAS Mobile Business class with Daniel Muther.

On this morning in the second half of September, we learn to understand ourselves - or our brain - better: How do we perceive things? How do we make decisions? And how can we use this knowledge to create a good user experience? Let's go…

What does user experience (UX) have to do with psychology?

Very much! Because various psychological factors play a role in the interaction between a person and a machine. This is the goal of UX: To reduce the cognitive and physical stress on users to a minimum. Translated, this means that we have to think about it as little as possible, the operation of e.g. the app is as intuitive as possible and the physical load is low, a machine e.g. ergonomically designed.

The "human factors" always have to be taken into account - i.e. everything that could influence us psychologically, cognitively or socially. The human being and how he interacts with the machine should be at the center of all considerations:

How we perceive things

But what about perception? Do all people perceive things the same way? Not at all - as a few simple examples of optical illusions show us. Lovers or dolphins? That is the question…

Perception and experience

How we perceive something always depends on our individual experience and what we have been taught. Adults tend to see lovers in the bottle on the left, while children discover dolphins. However, once you have learned the other way of looking at the picture, it can no longer be imagined without it.

Perception and context

In addition, our perception is also dependent on the context: two circles of the same size are perceived as different sizes, depending on which circles they are surrounded by.

The secret of the two filters

One reason why we perceive things so subjectively are our two filters:

  1. Filter: sensory perception. How we perceive an external object is determined by our brain. This perception is not the same for all people.
  2. Filter: Rating. How we rate something depends to a large extent on our character - e.g. which values ​​we grew up with and which experiences we have had.

→ First conclusion: What we know so far:

  • We seldom see the “true” reality because our brain often plays something for us.
  • We cannot influence this.
  • Our brain therefore determines how we perceive the world.
And what do we do with this knowledge now?

Gestalt laws

All of these findings help us to design an application, an interface or a machine that is as easy to understand for users as possible - and that can be used in the same way by as many as possible. The Gestalt laws help us with this. If you observe these laws, you already ensure a good 50% of a good UX - for example with a website:

Law of conciseness

In a group of similar objects, we notice the fastest one that stands out from the others through a certain feature (example below: octagonal star).

Law of similair

Things that are similar are grouped by our perception, i.e. understood as belonging together. Conversely, things that turn in will be importanten Distinguish characteristics, perceived as separate or independent from one another.

Law of proximity

Visual elements that are close together are more easily perceived as belonging together. Things that are further away are more likely to be viewed as separate.

Law of unity

We learned individual elements that have similar characteristics
n, to be seen in a larger context and thus to summarize the individual elements in forms or groups. This “sense” is so pronounced with us that we even mentally assemble individual elements to form a circle, although elements are missing.

Law of continuity

We always assume that lines follow a path known to us. This is usually the easiest way. In our example we assume according to the law that points 1 and 4 are connected by a line and points 2 and 3. However, we consider it rather improbable that points 1 and 3 could also be connected by a line .

The gestalt laws help us to meet the basic requirements for a good visual representation. But there are other perceptual phenomena that need to be taken into account:

Inattention blindness

When we focus heavily on one detail, we often fail to notice other things going on around us - like the gorilla in this film. The reason is the selective processing capacity of our brain. We only see what is relevant to us at the moment. On a website, the customer could e.g. For example, you cannot see the shopping cart button because your attention is being absorbed by another object.

These points should also be considered when building a website:

  • Conformity with expectations: We are used to certain designs, e.g. B. Placement of the home button at the top left
  • Reading direction: From top left to bottom right and following the "F pattern"
  • Banner blindness: We learned to hide banner ads. Important information on a website should therefore not be placed in a banner.

Phenomenon: orientation reflex

The red button that is displayed in the PowerPoint presentation cannot be ignored. This phenomenon can be used to direct the user's gaze to a certain object.

In websites, this phenomenon is taken into account with "transitions": when you click on an object, it moves very subtly (e.g. a shopping cart opens, an object moves to the foreground or background). This gives the user orientation as to where they are on the website.

How we decide

We often feel that we ourselves are masters of our decisions. However, there are external factors that influence us:


Not only our perception depends on the context, but also our decisions. For example, subjects in a study who have to choose between two equivalent offers suddenly decide in favor of offer A just because a supposedly bad attribute was added to offer B (in our example: There is no coffee in Rome, so you choose that Journey to Paris). This made the decision easier or even relieved of the test persons.

Another example: when deciding between two Economist subscriptions, the majority of subscribers opted for the inexpensive online subscription instead of the more expensive combined offer for the online and print edition. After the introduction of a pure print subscription at the same price as the combined offer, the majority opted for the combined offer. This “deception effect” is also called the decoy effect.

Our decisions are therefore influenced by various external factors. This is used in web design with the persuasive design.

Persuasive design

With the help of basic psychological knowledge, one tries to influence users. The following principles are used:

Social proof

People like to be influenced by the behavior of others. For example, you are more likely to sit in a café that already has guests. The empty restaurant next to it is considered to be the less good option. The more unsure we are about a topic, the more we tend to listen to others.

For example, we like to be influenced by good customer reviews on a comparison portal. However, if, for example, a restaurant has not yet received any reviews, we assume that something is wrong with this restaurant.

=> Tip: If you activate this rating tool on your own website, you should make sure in advance that some ratings are already available.


The principle is based on reciprocity: The customer shows himself e.g. B. recognizable for a free sample by subscribing to a newsletter. However, this should not work equally well for all nations, since such a "sense of responsibility" depends heavily on the mentality.


With their opinion on a product or service, experts influence the opinion of consumers (e.g. bloggers, YouTube stars, testimonials from stars or doctors). This category also includes: bestseller lists, test winners at Kassensturz, Mark Zuckerberg as an important influencer in the technology sector, opinions of colleagues on social media.

Scarcity, Scarcity

Users fear that the product could soon be sold out. This forces you to make an early purchase. Example: travel booking website, display of low stocks in online shops, teleshopping.


Whoever says A must also say B: If you have committed yourself to something (e.g. a certain lifestyle, value system), you have to do it consistently (support NGOs when they speak to you on the street).


And finally this ...

Our take home messages:

  • Perception is individual: the world as we see it is not the world that others see.
  • Many internal and external factors influence our perception.
  • We do not decide autonomously.
  • Persuasive techniques can have a huge impact on us.