Cognitive Psychology

1. Definition

Cognitive psychology is the study of the mental mechanisms involved in perception, memory, attention, decision-making, etc.
It helps design interfaces that match the cognitive limitations and habits of users.

2. Why Is It Important in UX?

Users don’t process information like machines
The brain has limited memory, attention, and reasoning
Good design reduces mental friction and makes decision-making easier

3. Key Cognitive Processes Relevant to UX

Table : 3. Key Cognitive Processes Relevant to UX
🧠 Process	💡 UX Implication
Perception	Gestalt laws (grouping, contrast, closure)
Attention	Limited resource → avoid visually overloading the interface
Memory	Miller’s Law: users can retain 7 ± 2 items at most
Learning	Reinforce memory through repetition, clarity, and feedback
Decision-making	Influenced by number of choices, layout, and emotional context

4. Cognitive Load

It’s the mental effort a user needs to process information.

3 types to understand:

Intrinsic: related to content complexity
Extraneous: related to poor presentation
Germane: helpful for learning

💡 UX Goal: reduce extraneous load

5. Useful Cognitive Biases & Laws in UX

Table : 5. Useful Cognitive Biases & Laws in UX
🧠 UX Bias / Law	✨ Practical Application
Von Restorff Effect	A unique element grabs attention
Hick’s Law	Too many choices slow down decision-making
Miller’s Law	Limit visible info (7 ± 2 items)
Fitts’s Law	Bigger targets = easier to click
Zeigarnik Effect	Incomplete tasks hold attention
Principle of Least Effort	Users choose the simplest path

6. Applying It to UX Design

Simple, clear, readable interfaces
Tailored UX Writing to guide effortlessly
Cognitive accessibility: avoid distracting animations, simplify labels
Personas enriched with psycho-cognitive traits

Conclusion

Cognitive psychology gives designers the tools to anticipate user behavior. It allows you to:

Design more intuitive interfaces
Reduce user errors
Maximize engagement and satisfaction