What People Bring with Them

Background

This chapter looks at:

• How memory works: Describes a basic model of human memory and considers some of the factors about how people process information in memory.

• How human vision works: Describes the basics of how the human eye works, eye movement during reading, visual acuity, and contrast effects.

• Cognitive resources and how they are allocated to tasks: Describes cognitive load, theories of how people allocate cognitive resources, and how allocation affects comprehension.

• Prior knowledge: The knowledge a person brings to a situation strongly influences how they interpret the information and comprehend the situation.

• Information biases: A bias is a systematic deviation from the expected path. Describes the various types of bias and how they affect comprehension.

• Mental models: Describes mental model theory, how people develop and use mental models, and design factors which influence mental model activation.

• Attention: Describes the types of human attention and how they affect understanding a situation.

Introduction

The research of cognitive psychology into how people process and interact with information plays a vital part in understanding how the human element of HII operates or, in cases of poor design, does not operate. Gulliksen & Lantz, (2003) pointed out that explicitly missing from much discussion of communicating information are the human issues. The issues that are the focus of cognitive psychology research. Of course, a major hindrance to crossing over is the framing of the psychology research itself and the need for it to be translated and integrated into something meaningful for an audience focused on HII—a non-trivial task. Wickens and Hollands (2000) were able to perform that translation for engineering psychology and human factors, but their scope was too broad for HII and technical communication, with a significant portion of their research discussing plant control and aviation design issues of concern for industrial engineering and ergonomics.

In document design, Mirel, Feinberg, & Allmendinger (1991) found the “active learning needs are inseparable from task type and complexity” (p. 82). Research on poorly designed interfaces and documents shows people getting frustrated with the basics and failing to conceptualize the appropriate principles for properly interacting with the system.

The poorly designed document fails to provide or support the necessary HII of the people interacting with the information. In complex tasks, the interactions operate along multiple dimensions and, during the interaction, changes occur along each of those multiple dimensions, but designers often fail to consider all dimensions. As a result, design failures occur because of problems in an unanalyzed dimension, often the dimension of the person’s cognitive processes (Rasmussen, Pejtersen, & Goodstein, 1994). A dimension that often goes unanalyzed because design teams concentrate on tasks as a program concept, rather than a real-world action performed by a person. In other words, they define them as a computer task rather than an HII task. Design teams need to understand how the people think about information, the system and the decisions made with the system. They need to understand people’s cognitive processes and what factors influence the mental processing of information. An understanding which must be viewed “in terms of the behavior-shaping goals and constraints that define the boundaries of a space within which actors are free to improvise guided by their local and subjective performance criteria” (Rasmussen, Pejtersen, & Goodstein, p. 23).