The document discusses design implications based on cognitive psychology principles for user interface design, focusing on aspects such as memory, attention, cognition, and affordance. It emphasizes that understanding user memory types and cognitive processes leads to more effective interfaces that improve usability and user experiences. Additionally, it highlights the importance of design elements like metaphors, prototypes, and gestalt principles in enhancing user interaction with digital interfaces.

1. GROUP 9
DESIGN IMPLICATIONS
 THE MODEL HUMAN PROCESSOR
 COGNITION
 ATTENTION
 MEMORY
 PERCEPTION
 RECOGNITION
 INTERFACE METAPHORS
 AFFORDANCE
 GESTALT PRINCIPLES
 MENTAL MODELS
 PROTOTYPING
MEMBERS
MBAKA AGGREY
JOAN CHELENGAT
NIXON CHERUYOT
RONNIE ODHIAMBO
COLLINS OMWOYO

2. MEMORY
The Model Human Processor Analogy: “Processing and storage facilities in a
computer system with the perceptual, cognitive, memory and motor activities of a
computer user.” Memory refers to the ability to store and recall information over
time. It refers to the storage of information in the brain and subsequent recall of
this information at a later point in time. It is important to understand the impact of
the user's memory on the design of the user interface in order to develop
interfaces that are easy to use and understand. The design of an interface based
on the characteristics of the user's memory can result in better recall and retention
of the information contained in the interface. The use of virtual reality and touch-
sensitive screens has been shown to improve the user's memory recall of the
information presented in an interface.

3. Types of Memory
Sensory Memories: They originate from sensory organs and are stored for a
short period of time. In design, visual sensory memory (iconic memory), is the
raw information from optic nerves that is stored and processed without conscious
effort (Preattentive Processing).
Short Term Memories: These are sensory memories of interest to us and they can
be retained for longer if rehearsed. The capacity of short term memories can
be increased by chunking (grouping items to form larger items).
Long Term Memories: These are consciously transferred short term memories.
Informational visualizations are often not committed to long term memory.

4. Design Implications
• Short term memory defines screen design and usability guidelines such as
distinguishing visited links in browsers.
• To support recognition rather than recall; visual hierarchy is used to show
organization, the number of elements in each interface is reduced and larger
interface contexts are divided into smaller chunks (George A Miller’s Theory).
• Designers are supposed to enable self-generation through interfaces that
allow users to influence the customization because intentionally customized
interfaces are easier to recall (Jakob’s Law of Internet User Experiences).

5. Cognition
Cognition refers to the ability of the brain to understand and process
information. In the field of user interface design, it has been shown that a
good user interface is not only easy to use but also effective and
understandable. It is therefore important to consider the user's perspective to
develop effective and efficient user interfaces.
Cognition has two general modes:
• Experiential
• Reflective

6. Experiential Cognition
Patterns of information are perceived and assimilated. Appropriate responses are
generated without apparent effort. Essential to skilled thought and behavior since it
appears natural but might need training and experience.
Reflective Cognition
Involves thinking, comparing and decision making. Often leads to innovation and
creativity. Requires the ability of a user to store temporary results and make
inferences from stored knowledge.
Implicates design because designers have to provide a theoretical basis for
cognitive models of users. This will often characterize computer-mediated cognitive
tasks as well as how information is processed at the interface.

7. Attention
Attention refers to the ability of the brain to focus on specific items or events in
the environment. it is the cognitive process of selectively focusing on specific
information while disregarding other information in the environment. It is
taking possession by the mind in clear and vivid form, of one out of what may
seem several simultaneous possible trains of thought.
Factors that might affect attentional focus include:
• Movement and Change
• Color Shifts
• Size and Intensity
• Number of stimuli

8. Design Implications
Make information salient when it needs to be
Use techniques that make things stand out like color ordering, spacing,
underlining and animated visuals.
Adopt temporal cues on user interfaces such as progress bars.

9. Recognition
The major difference between Recognition & Recall is the number of cues
provided or given by the context that can help memory
retrieval. Recall has fewer cues than Recognition that’s why it is
difficult and error-prone.
In simple terms, the user’s should provided everything like visual cues, options,
actions, instructions available which helps to avoid the memory load or cognition
load and make the decisions error-prone.

10. Implications For Design
The traditional affordance cue for a link is blue, underlined text. But that’s no
longer always the case. Underlines can be omitted, and colors may be changed.
But users still need to know that certain text is a link that they can click on. UX
designers can communicate this by using a certain color for only links and
nothing else, and by not underlining things that aren’t links. Because of
patterning, users have come to expect that underlined text is a link, so don’t
confuse them.

11. INTERFACE METAPHORS
A metaphor is a mapping process from a familiar object to an unfamiliar object.
Roles
*Facilitates interface development
* Facilitates maintenance
* Facilitates user orientation
Interface metaphors evoke an initial mental model in users of the system’s structure
and operation.
Learning and retention of a system’s functionality is considerably facilitated by
meaningful and consistent metaphors.

12. Interface metaphors have several design implications, including:
They help users understand and navigate a digital interface more easily by
providing familiar and recognizable concepts.
They can make a digital interface feel more intuitive and less intimidating to
use as users can leverage their prior knowledge and understanding of
physical objects.
They can help create a consistent and predictable interface as users can
apply their understanding of the metaphor to similar interfaces in other
contexts.

13. IMPLICATIONS FOR DESIGN
Typewriter Metaphor: This metaphor is evoked easily and should be avoided.
Desktop Metaphor: The direct association of user activity, and it is slowly
disappearing.
Filing Cabinet Metaphor: Used in online documentations, Multi-tab Web
Configurations and Document Handling.
Building/City Metaphor: Used to depict virtual worlds

14. AFFORDANCE
The relationship between a person and a physical or digital object. UI affordances are perceivable
actionable possibilities. Users observe a UI and decide which actions are possible based on their
expectations and previous experiences. Categorized as:
i. Explicit: Visible appearances clearly indicate possible actions
ii. Hidden: Hidden by default and become apparent once right conditions are met (Hamburger).
iii.Negative: Obvious that UI element does not currently afford any capabilities (Grayed Content).
iv. False: Offer false suggestions to users but fail to accomplish functionality.

15. Implications for Design
Designers should follow design conventions by providing signifiers such as Home Icon>
Homepage. Designers should provide immediate user feedback through functional
animations
• They help us understand what actions are possible in an interface and how to perform
them.
• They reduce the need for explicit instructions or labels as visual cues themselves can
provide enough information for the user to understand how to interact with an element.
• They can help create a consistent and predictable interface as users can learn and apply
affordances from one interface to others.

16. Mental models
• They are what people have in their heads and what guides their use of things.
• Designers design a conceptual model into their system in order to make it
graspable and coherent to users.
• Mental models are vehicles for exploration and illustration.

17. Design Implications
• They help bridge the gap between the user's understanding of the real world
and their understanding of a digital interface making the interface feel more
intuitive and less intimidating to use.
• They can help create a consistent and predictable interface as users can
apply their mental models to similar interfaces in their contexts.
• They can help users to understand the purpose and behavior of an interface
as mental models provide a framework for understanding and interaction.

18. Prototyping
Prototyping is an experimental process where design teams implement ideas
into tangible forms from paper to digital. Teams build prototypes of varying
degrees of fidelity to capture design concepts and test on users. You can refine
and validate your designs with prototypes so your user interface can release
the right mix of needs.

19. Implications for Design
• Designers can have a tool to experiment with associated parts of the users’
needs and problems—therefore, you can get insights into less-obvious areas
of the users’ world (e.g., you notice them using it for additional purposes or
spot unforeseen accessibility issues such as challenges to mobile use).
• Prototyping improves time-to-market by minimizing the number of errors to
correct before user interface product releases of products.

20. GESTALT THEORY
• German term translated roughly as whole or form.
• These are concepts that make unity and variety possible in design. They are concerned with
the relationship between the parts of a composition and the whole.
• “This theory assert, in belief that no figure is ever perceived except in relation to a
background” Kurt Koffka
• The theory attempts to describe how people tend to organize visual elements into groups or
unified wholes when certain principles are applied.

21. GESTALT PRINCIPLES
1. Proximity
2. Similarity
3. Continuity
4. Closure
5. Symmetry
6. Figure/Ground
7. Common Fate

22. Proximity
• The relative distance between objects in a display affects our perception of
whether or not are organized into subgroups.
• Close arrangement of elements causes group association:
Close Proximity = Unity
Shapes don’t have to be regular or have the same size (Flame Logo)

23. Similarity
• Objects that look similar appear grouped
• When similarity occurs, an object can be emphasized if it is dissimilar to others <Anomaly>.
• There can be similarity of shape, color, alignment, size, value, tone or combinations of other possibilities.
 Breaking the pattern of similarity creates focal points
 The more commonality amongst elements the more the coherence (Beatles Album Cover A hard Days
Night)

24. Continuity
• Occurs when the eyes are compelled to move through one object and continue to other objects
preferring to see a single continuous figure.
• Users resolve ambiguity by adding in missing data in such a way that they perceive whole
objects.
• Perception of simplest paths (continuous forms) rather than complex paths (disconnected pieces).
 IBM Logo

25. Closure
• Technique uses human eyes’ tendency to see closed shapes.
• Users automatically try and close open figures so that they are seen as whole
objects rather than bits of line.
• When a viewer’s perception completes a shape, closure occurs.

26. Symmetry
• Viewers tend to parse complex images in a way that reduces complexity.
• Even when there are multiple interpretations, our brains pick the simplest one.
• Asymmetry forces us to focus on what is different
Pepsi Logo

27. Figure/Ground
• Our brains try and separate images into foreground and a background.
• Uses the idea of light and shade
• Could be used to introduce deliberate ambiguity as a visual trick.

28. Common Fate
• Similar to proximity and similarity but concerning moving objects since things that
move with similar patterns are seen as grouped.
Isomorphic Correspondence: Makes us think of something while looking at
something else.
When we encounter vague, ambiguous and difficult design messages, the Gestalt
principles can help us define the problem and identify the solution.

29. Conclusions
Recent advances in user interface design now consider the entire user experience
as part of the design activity. It is not enough to simply consider the user interface,
but the entire user experience is the important design issue.
The discussion on user interface design must include the entire user experience. The
user experience is a broad concept that applies to all aspects of a person’s
interaction with the system.
The user interface, which is the set of inputs and outputs that the user sees and
interacts with, must fit within this larger concept of the user experience. User
interface design must consider all aspects of the user characteristics as well as the
myriad devices that the user will interact with.

30. Useful Resources
• Human reactions to information processing according to the Model Human
Processor
• Card, Morgan and Newell on Design Tools for Effective User Interfaces
• George A Miller Theory on Types of Memory
• Cognition in Functional Systems and the Model Human Processor
• Jakob’s Law of Internet User Experiences
• Course Material Review: Jenny Preece Human Computer Interaction