Remembering planned activities, resuming tasks previously interrupted, recalling the names of colleagues, sustaining focused performance under the pressure of interruptions, ensuring that we don't miss important information…these are only a few examples of critical activities whose performance is guided by attentional processes. This chapter proposes that knowledge about attentional processes can help us design systems that support users in situations such as those described above. The first part of the chapter gives an overview of some of the essential theoretical findings about human attention. The second part analyses attentional breakdowns and how those theoretical findings may be applied in order to design systems that either help avoid attentional breakdowns or assist in recovering from them.

Introduction

Current information and communication technologies concentrate on providing services to users performing focused activities. However, focused activity is no longer the norm. Users are often interrupted, they switch between the contexts of different devices and tasks, maintain awareness about the activity of distant collaborators and manage very large quantities of information. All this results in high cognitive load that may hinder users' overall achievements.

In order to address interaction in a more realistic manner, we have been working on the development of systems that are capable of supporting the processes that govern human cognitive resources allocation: attentional processes.