1. Comp 15 - Usability and Human Factors
Unit 3c - Cognition and Human Performance
This material was developed by Columbia University, funded by the Department of Health and Human Services, Office of the National Coordinator for Health Information Technology under Award Number 1U24OC

2. Mental Models
Reason about possible outcomes resulting from actions (e.g., clicking on this link)
Retrieve episodes from memory to understand a new situation (e.g., last time my hard disk failed)
Psychological construct for describing how individuals form internal models of systems
Representations of parts in a system
Understanding of how different parts of a system connect
Mental models can be used to characterize an individual‘s:
Component 15/Unit 3c
Health IT Workforce Curriculum Version 2.0/Spring 2011

3. Health IT Workforce Curriculum Version 2.0/Spring 2011
Mental Models (cont.)
Running of a model corresponds to a process of mental simulation which can be used to generate possible future states of a system from observed or hypothetical state
Use of a mental model engage temporal and spatial reasoning
Component 15/Unit 3c
Health IT Workforce Curriculum Version 2.0/Spring 2011

4. Mental Models (cont.) Predict/Anticipate and Explain
How people form internal models of systems
“If I click OK on a dialogue box button, what will happen next”?
Running a model a process of mental simulation to generate possible future states
“Why didn’t the program print”
Can be used to explain what happened
Component 15/Unit 3c
Health IT Workforce Curriculum Version 2.0/Spring 2011

5. Health IT Workforce Curriculum Version 2.0/Spring 2011
ATMs
1 image of ATM screen where you can select what you want to do.
1 image of ATM screen where you can enter amount of cash to withdraw or choose pre-set option for fast cash.
Component 15/Unit 3c
Health IT Workforce Curriculum Version 2.0/Spring 2011

6. Limitations of Conventional Information Processing & HCI
Limitations in application to real world contexts
Ways people adapt and make use of tools is poorly understood
People don’t fly solo (teams, collaborations)
Theories too low level, limited in scope
Limitations in application to real world contexts
Theories too low level, limited in scope
Ways people adapt and make use of tools is poorly understood
People don’t fly solo (teams, collaborations)
Component 15/Unit 3c
Health IT Workforce Curriculum Version 2.0/Spring 2011

7. Limitations of Conventional Information Processing & HCI
Narrow focus on the rational/cognitive processes of the solitary individual
Knowledge in the head as opposed to in the world
Distributed Cognition
External representations
Cognition as distributed in the social world
Narrow focus on the rational/cognitive processes of the solitary individual
Knowledge in the head as opposed to in the world
Distributed Cognition
External representations
Cognition as distributed in the social world
Component 15/Unit 3c
Health IT Workforce Curriculum Version 2.0/Spring 2011

8. Health IT Workforce Curriculum Version 2.0/Spring 2011
Insert Clip Art
Component 15/Unit 3c
Health IT Workforce Curriculum Version 2.0/Spring 2011

9. Health IT Workforce Curriculum Version 2.0/Spring 2011
To Sit or Not to Sit?
Chair Schema
Legs: 4
Surface affords sitting: Yes
Availability status: Empty
Awesome!
Image of man looking at chair and thinking about sitting or not sitting.
Component 15/Unit 3c
Health IT Workforce Curriculum Version 2.0/Spring 2011

10. Distributed Cognition
Intelligence as interwoven processing of internal and external information
Focus on the interplay between internal and external representations
Emphasis on real-world settings and ethnography
The role of artifacts in task completion
Organization of mind as an emergent property of interactions among internal and external resources
Component 15/Unit 3c
Health IT Workforce Curriculum Version 2.0/Spring 2011

11. Affordances Perceive the possibilities for action (physical property)
Gibson: World is directly perceived based upon abundant sensory information
Attributes of objects that allow people to know how to use them
Door handles, water faucets, elevator panels, post-it notes, menus, buttons, lists, hypertext, scroll bars
User needs to learn the meaning and function before knowing how to act
Coordination, sequencing, feedback
The way structures in the environment invite people to do something
Component 15/Unit 3c
Health IT Workforce Curriculum Version 2.0/Spring 2011

12. Distributed Cognition
Image of woman working at computer.
Distributed Cognition
Coordinating internal (user’s mind) and external (interface, environ) resources
Component 15/Unit 3c
Health IT Workforce Curriculum Version 2.0/Spring 2011

13. Nurse Case Manager Workflow
Image of woman working with 2 computer monitors.
Component 15/Unit 3c
Health IT Workforce Curriculum Version 2.0/Spring 2011