1. CEN3722 Human Computer Interaction Attention and Memory
Dr. Ron Eaglin

2. Objectives Understand the implications of attention for design
Focus and divided attention
Automating processing
Chunking
Limitations of human memory

3. Attention Design should help users find information they need
Structure interface – easy to navigate
Correct amount of information
Use groupings
Use correct ordering

4. Attention
Focused Attention – Attend to one item at the exclusion of competing stimuli
Divided Attention – Attend to more than one stimuli at a time
These affect the how well we interact with a system

5. Attention Users will be distracted Suspended activities Cognitive Aids
Users forget where they left off
Forget if task was completed
Cognitive Aids
Reminders of status of activity – status bar
Reminder of completion of activity – reminder of completion

6. Attention
Use Spatial Cues
Use Temporal Cues

7. Spatial Cues Name Address Phone # Jane Done 423 J St. 555-1234
Example A:
Example B:
Name Address Phone #
Jane Done J St
Yu Chen Smith St
Kay McBride Jones St
John Smith A St
Jane Done
423 J St.
Yu Chen
874 Smith St.
Kay McBride
848 Jones St.
John Smith
123 A St.

8. Temporal Cues Complete Homework 1 Overdue Complete Homework 2
Task
Deadline
Complete Homework 1
Overdue
Complete Homework 2
Due Friday
Complete Homework 3
Due Next Friday
Take Quiz 1
Due in 2 Weeks

9. Attention
Flashing or Movement
Warning !!
Audio Warnings

10. Attention-Urgent Simple message Requires user response
Information Needing Immediate Attention
Requires user response

11. Attention – Informational
Status information – status bar at top or bottom of screen.
Use consistency in area of the screen where status is displayed.

12. Attention – Help and Assistance
Available upon request – but easy to find and consistent

13. Automatic Processing Overlearned Activities
Activities that have become automated
Listening
Reading
Walking
We do not consciously think about these activities

14. Automatic Processing
More practice leads to improved performance – we become skilled and eventually performance is automatic
Characteristics
Fast
Demands minimal attention
Does not interfere with other activities
Unavailable to consciousness

15. Experiment – Say Colors Out Loud
Which one does it take more focus to
State colors?
Automatic processes (reading) conflict
with process of perceiving color.
Stroop Effect

16. Multi-Store Memory Model
Input or stimuli
Sensory store
Loss from sensory store
Select and actively process
Working Memory
Loss from short-term memory store
Long-term Memory
Decay, interference,
loss of strength in
long-term memory store

17. Working Memory
Most people can hold 7 “chunks” of information in working memory
Chunk = number, item, word
Magical Number 7 + or – 2
Chunks depend on person, experience, context
Chunking means meaningfullness

18. Memorize – (3 sconds)

19. Memorize (3 Seconds)
3002
2002
1002
0002

20. Chunking Same number – different chunking
(16 bits vs. 4 bits vs. 1 bit (pattern)

21. Memorize
you
welcome we
today
kindly
sir
thank
how
fine
are

22. Memorize
Welcome, how are you today?
Fine, we thank you kindly!

23. Memorization – Different number of chunks
you
welcome we
today
kindly
sir
thank
how
fine
are

24. Recognition vs. Recall Make things visible, making recognition easier
We can recognize material far more easily than we can recall it from memory
Obvious implications for interface design:
Make things visible, making recognition easier
Compare: menus vs. command line
Recognition: knowledge in the world
Recall: knowledge in the head

25. Familiarity – Words and meaning
He has a predilection towards autonomous artistic creation
He likes to create things on his own

26. UI Design
Items that need to be remembered at the interface should be as meaningful as possible
Problems with command line interfaces
e.g., command names and icons should be selected according to meaningfulness
cp vs. copy
rm vs. remove
cat, grep, lint, mv, pr, lpr (huh?)

27. UI Design

28. Summary Design interfaces to help users find information/perform tasks
Use cues (grouping, color, sound, icons, familiar words)
Understand focused vs. divided attention
Understand automatic processing
Understand limitations of human memory
Understand Chunking
Recognition vs. recall