Cognitive Frameworks for HCI
The aim of this article is to introduce two cognitive frameworks: human information processing, which has formed the basis of much understanding in HCI, and an alternative cognitive framework, known as distributed cognition.
The notion of information processing has played a fundamental role in HCI by providing a theoretical basis for cognitive models of users. However, there are a number of problems with the information processing approach and several researchers have begun to reconceptualize the cognitive aspects of HCI, from other perspectives, with the aim of developing an alternative approach that overcomes these problems. One alternative is distributed cognition, in which the central concern is to re-embody cognitive processes in a real-world context. Instead of conceptualizing an individual's cognitive tasks when interacting with an individual computer, the distributed cognition approach attempts to characterize the computer-mediated, cognitive activities of a group of people working together in a given setting.
A cognitive perspective
The dominant framework that has characterized HCI has been cognitive. In general, cognition refers to the process by which we become acquainted with things or, in other words, how we gain knowledge. These include understanding, remembering, reasoning, attending, being aware, acquiring skills, and creating new ideas. The main objective in HCI has been to understand and represent how humans interact with computers in terms of how knowledge is transmitted between the two. The theoretical grounding for this approach stems from cognitive psychology: it is to explain how human beings achieve the goals they set. Such goal-oriented activity is comprised of performing cognitive tasks that involve processing information.
Human information processing
During the late 1970s, the main paradigm in cognitive psychology was to characterize humans as information processors; everything that is sensed (sight, hearing, touch, smell, and taste) was considered to be information which the mind processes. The basic idea was that information enters and exits the human mind through a series of ordered processing stages. Stage 1 encodes information from the environment into some form of internal representation. In stage 2, the internal representation of the stimulus is compared with memorized representations that are stored in the brain. Stage 3 is concerned with deciding on a response to the encoded stimulus. When an appropriate match is made the process passes on to stage 4, which deals with the organization of the response and the necessary action. The model assumes that information is unidirectional and sequential and that each of the stages takes a certain amount of time, generally thought to depend on the complexity of the operation performed.
Extending the human information processing model
Two main extensions of the basic information processing model are the inclusion of the processes of attention and memory. The below image shows the relationship between the different processes. In the extended model, cognition is viewed in terms of:
How information is perceived by the perceptual processors
How that information is attended
How that information is processed and stored in memory
Extended stages of the information processing model (adapted from Barber 1988)
Broadening the cognitive framework
It is becoming increasingly recognized that a cognitive perspective of the individual user performing various tasks at the interface is an inadequate conceptual framework for HCI. Specifically, the traditional cognitive approach has neglected the importance of how people work in real work when using computer systems. Moreover, there has been a lack of consideration of other aspects of behavior besides how users process information at the interface - namely, how people interact with each other, and other objects besides computer systems, in the environment they are in. Another important concern is the emergence of alternative and interdisciplinary frameworks that are intended to inform the design of real systems for real people to carry out real work activities in real organizational settings.
The goal of this theoretical framework is to provide an explanation that goes beyond the individual, to conceptualizing cognitive activities as embodied and situated within the work context in which they occur. Primarily, this involves describing cognition as it is distributed across individuals and the setting in which it takes place. The people, computer systems, and other technology (sometimes referred to as cognitive artifacts by psychologists) and their relations to each other in the environmental setting in which they are situated are referred to as functional systems.
One of the main goals of distributed cognition approach is to analyze how the different components of the functional system are coordinated. This involves analyzing how information is propagated through the functional system in terms of technological, cognitive, social, and organizational aspects. To achieve this the analysis focuses on the way information moves and transforms between different representational states of the objects (media) in the functional system and the consequences of these for subsequent actions. A main concern of the distributed cognition approach, therefore, is to map out how the various representational states of the functional system are coordinated across time, location and objects.
In many settings, the coordination of distributed cognitive activities is able to be maintained. However, there are also many situations when this coordination breaks down. The term breakdowns are used to describe the various incidents, problems, inefficiencies, and accidents that arise in the work setting. Often the breakdowns are very subtle, and their causes are analyzed in terms of the interactions between the multiple components of the functional system.