Design Psychology
Key question
How do we design responsibly?
Those who understand how people perceive and make decisions can either help them or take advantage of them. Responsible design therefore asks about the purpose first: who benefits from this decision?
This module covers dark patterns, legal frameworks, inclusion, and the methods you use to test assumptions. It concludes with the final project.
Learning objective: You recognise manipulative design, justify ethical decisions, and test your solutions using appropriate methods.
First ask who benefits from a design.
8.1 / Dark Patterns
Some design works against the users.
The term dark patterns (Harry Brignull, 2010) refers to design patterns that nudge people into making decisions that are not in their best interest. Today, they are also known as deceptive patterns.
Typical examples: hidden costs that only appear right at the end; a subscription that can be started with a single click, but cancelled only through numerous steps; confirmshaming, such as opt-out copy like 'No, I don't like discounts'; pre-ticked boxes; manufactured scarcity ('Only 2 rooms left!'); and persistent nagging.
A simple test: would users make the same decision if they had all the information clearly, completely, and without pressure in front of them? If not, the design is likely manipulative. Dark patterns also harm the provider in the long run: they cost trust and can lead to legal consequences.
If you have to hide the design, something is wrong.
Many dark patterns are now legally problematic as well. In the EU, consent must be freely given and unambiguous: pre-ticked boxes are not sufficient, and refusing consent should be as easy as giving it. In Switzerland, the revised Data Protection Act (in force since 2023) requires the same where consent is necessary, and the Unfair Competition Act (UWG) prohibits misleading claims such as fabricated scarcity.
8.2 / Lead or mislead
The difference lies in intention, openness, and choice.
Legitimate guidance helps people achieve their own goals: it is transparent, allows genuine freedom of choice, and serves the user's best interests. Deception and exploitation obscure intent, make alternatives difficult, or take advantage of vulnerabilities.
Four test questions help make the distinction:
QUESTION 1
Recognisable?
Is the intent clear to users?
QUESTION 2
Can be rejected?
Can the option be easily declined or undone?
QUESTION 3
Helpful?
Does the design also benefit the individual themselves?
QUESTION 4
Presentable?
Would you disclose the design, for example in a press release?
Creators carry responsibility. They can challenge requirements, suggest alternatives, and say no when in doubt. Good arguments include trust, customer retention, and applicable law.
Leadership is open, deception hides.
8.3 / Inclusion
Design for all starts at the margins.
Accessibility means that as many people as possible can perceive, operate, and understand content. The WCAG summarises this into four principles:
01
Perceptible
Sufficient contrast, alternative text for images, subtitles for videos.
02
Operable
Everything accessible by keyboard, plenty of time, large click targets.
03
Understandable
Clear language, predictable behaviour, helpful error messages.
04
Robust
Clean code that also works with assistive technologies such as screen readers.
Inclusive design goes beyond permanent impairments. Carrying a child leaves you temporarily one-handed; reading in the sun causes a situational drop in contrast. What helps people with disabilities often helps everyone.
Accessibility is not an afterthought to be tackled at the end, but belongs from the very start to the concept, colour scheme and structure.
What is necessary for a few helps many.
8.4 / Methods
Each method answers different questions.
Choose the method based on what you want to know:
SHOWS: OPINIONS
Survey & Interview
Expectations and reasons. Surveys reach many people, while interviews delve deeper. They show what people say, not necessarily what they do.
SHOWS: BEHAVIOUR
Usability test
People complete typical tasks, and you observe where they hesitate or struggle. Just a few people uncover a lot of issues.
SHOWS: WHAT WORKS
A/B test
Compares two variants across many real users based on a key metric. Shows what performs better, but not why.
SHOWS: GAZE PLOT
Eye tracking
Shows where the gaze is directed, but not whether something was understood or why.
Good research combines methods: first understand (interviews, observation), then compare (testing), whilst openly acknowledging limitations and uncertainty.
Those who only know one method only see part of the picture.
Final project
Redesign with a psychological rationale
Task: Choose an existing design and improve it without guessing. Justify every change using concepts from the course and verify them wherever possible.
STEP 1
Selection
Choose an existing design (website, app, packaging, or poster) that interests you and that you are allowed to document.
STEP 2
Analysis
Analyse it using at least four lenses from the analysis toolkit. Document the observation, concept, effect and evidence for each.
STEP 3
Draft
Revise the design. Document every change following the template: I changed X because principle Y suggests that Z.
STEP 4
Review
Test your solution using at least one simple method, for example five short test interviews. Record what was confirmed and what was not.
STEP 5
Reflection
Where could your solution influence users, and is that justifiable? Apply the test questions from 8.2 to this end.
Assessment criteria: understanding of the concepts, quality of reasoning, design quality, methodological rigour, and reflection.
Without justification, a change is merely a matter of taste.
Analysis toolkit
Every concept in the course is an analytical tool.
For the analysis in the final project, you will use the concepts from this course as tools. Document each observation in four steps:
STEP 1
Observation
What exactly do you see? Describe neutrally, without judging.
STEP 2
Concept
Which principle from the course explains the observation?
STEP 3
Effect
What impact does this have on users: What do they understand, feel, or do?
STEP 4
Receipt
How can this assumption be tested, perhaps with a blink test or a trial conversation?
These eight lenses organise the tools according to the four levels from Module 01. Each card leads to the section where you will learn about the tool:
PERCEIVE / MODULE 02
Grouping
Which elements are perceived as a group? Do visual groupings match content-related ones? Tool: Gestalt principles.
PERCEIVE / MODULE 03
Attention & Hierarchy
What is the first thing you notice in the squint test? Does the visual hierarchy match the users' task?
PERCEIVE / MODULE 04
Colour & Legibility
Is the contrast sufficient? Does colour alone convey information? Are the font size and line length legible?
THINKING / MODULE 05
Cognitive load
Where does unnecessary cognitive load arise? Is information grouped meaningfully? Do signifiers align with the mental model?
THINKING / MODULE 05
Heuristics
Which of the ten heuristics are violated, and how severe is each problem?
FEEL / MODULE 06
Impression & Brand
What first impression and tone of voice are created? Do they suit the content and target audience?
ACT / MODULE 07
Decision
Which defaults, anchors or phrasing guide the choice? How easy is the desired action?
ETHICS / MODULE 08
Lead or deceive
Is the intention clear, can it be refused, does it benefit the individual? Is the design accessible?
First observe, then identify, then justify.