Philip Barnard

Interacting cognitive subsystems: A systemic approach to cognitive-affective interaction and change

Abstract Interacting Cognitive Subsytems (ICS) is a comprehensive systemic model of the organisation and function of the resources underlying human cognition. in this paper we use ICS to provide a conceptual framework for understanding normal and dysfunctional cognitive-affective relationships, and their modification. ICS proposes nine interacting cognitive subsystems, each specialised for handling a specific type of information. We describe the operations of ICS and its account of emotion development and production. ICS emphasises the importance, as part of the total cognitive configuration producing emotion, of a schematic synthetic level of processing that integrates both propositional meaning and direct sensory contributions. Processing at this level corresponds, subjectively, to holisitc “sense” or “feeling” rather than to thoughts or images. We illustrate this emphasis by comparison of ICS with the model underlying cognitive therapy. By applying ICS to the maintenance of depression, we illustrate th...

Consistency and compatibility in human-computer dialogue

To tackle problems of human-computer interaction the traditional scope of humanmachine studies needs extending to include the complex cognitive skills of understanding, communication and problem solving. This extension requires a fusion of the conceptual and empirical tools of human factors with those of cognitive psychology. A methodological approach to this fusion is outlined as a background for three studies of structured human-.computer dialogue. The studies involved a task in which secret messages were decoded in a number of discrete steps corresponding to computer commands. Each “command” required two numeric arguments. The study investigated underlying variables using questionnaire techniques in addition to user performance in an interactive version of the task. Three factors concerning the order of arguments in a command string were investigated: the consistent positioning of a recurrent argument, the relationship between argument entry order and their order in natural language, and the relationship between argument entry order and the position of argument values on a VDU. In Study I software specialists were asked to design command structures for the task and to give reasons for their choices. In Study II naive subjects were asked to choose between telegrams in which alternative argument orders were expressed in terms of alternative word orders. In the interactive version of the task, used in Study III, positionally consistent systems were most readily learned, but this depended on having the recurrent argument in the first position. With positionally inconsistent systems there were reliable effects due to the position of the direct object of individual command verbs.

Systems, interactions, and macrotheory

A significant proportion of early HCI research was guided by one very clear vision: that the existing theory base in psychology and cognitive science could be developed to yield engineering tools for use in the interdisciplinary context of HCI design. While interface technologies and heuristic methods for behavioral evaluation have rapidly advanced in both capability and breadth of application, progress toward deeper theory has been modest, and some now believe it to be unnecessary. A case is presented for developing new forms of theory, based around generic “systems of interactors.” An overlapping, layered structure of macro- and microtheories could then serve an explanatory role, and could also bind together contributions from the different disciplines. Novel routes to formalizing and applying such theories provide a host of interesting and tractable problems for future basic research in HCI.

Design practice and interface usability: Evidence from interviews with designers

Research into human-computer interaction (HCI) is mainly conducted by engineering psychologists, cognitive psychologists and computer scientists. The principal consumers of applied HCI research, on the other hand, are human factors practitioners and system designers and developers. The HCI researcher who believes his or her findings to be of practical relevance has therefore to consider the interface between researcher and practitioner as well as that between system and user: the products of HCI research must not only be relevant but also “user-friendly” to the practitioner. This problem is not merely one of communication between different professional communities, as the optimal route for the translation of research findings into terms that will be of practical use in the design process is itself a matter of considerable uncertainty and debate. Thus there are many instances in the research literature where apparently contradictory recommendations can all too easily be drawn from findings based on sound but, by its very nature, limited experimentation (e.g., compare the findings of Landauer et al., in press, Ledgard et al., 1980, and Scapin, 1981, on naming text-editing operations).n One of the prerequisites for tackling both the communication problem and the translation problem is an understanding of relevant aspects of decision-making in design which influence the usability of the end-user interface. This is so for three reasons. First, an appreciation of the nature of design practice will at least help identify those areas where research input might have the greatest impact and allow researchers to direct their efforts towards them. Second, it may identify possible modifications to existing design practice which would allow research input to be used more effectively. Finally, it would be somewhat surprising if current design practice were not to furnish researchers with any insights into the underlying processes of users. The experience and skills of the practitioner should be a valuable source of information for the HCI researcher. For these reasons, we have been documenting some of the relationships between design practice and the usability of systems for use by non-experts. While there is considerable literature on programming behaviour (e.g. Mayer, 1981), reports of design behaviour are rare, other than occasional descriptions by practitioners of the interface design of their own products (e.g., Botterill, 1982; Smith et al., 1982). This paper focusses on the influence of the individual designers decision-making. Evidence is taken from interviews with experienced system designers concerning design issues influencing the nature of the user interface which had arisen with systems they had recently worked on. For two of the systems usability investigations had been performed (see Lewis & Mack, 1982 and Hammond et al., 1983).

Using Interaction Framework to guide the design of interactive systems

Understanding the properties of interactions is essential to the design of effective interactive systems involving two or more agents, and to the evaluation of existing systems. This understanding can inform the design of multi-agent systems by helping the designer identify properties that a system should conform to. In addition, a focus on the properties of interactions can lead to a better understanding of the space of possibilities, by recognizing features of multi-agent systems which are often simply incidental outcomes of design, not explicitly considered in the design specification. We present an Interaction Framework, in which abstract interactional requirements and properties can be expressed in a way which is not biased towards the perspective of any one agent to the interaction. These can be used to derive requirements on the design of computer systems, to highlight those aspects of users which influence the properties of the interaction, and hence to guide the design of the interactive system.

Learning and remembering interactive commands in a text-editing task

Abstract Users of interactive computer systems often experience difficulty in learning and remembering the command vocabulary needed to communicate with the system. This study investigates how task and vocabulary differences affect initial learning and subsequent memory for commands used in a simple editing task. Systems with semantically specific terms were learned no more quickly than systems with semantically general terms, but the nature of the command vocabulary induced different learning strategies. Users of the specific vocabulary made less use of help (provided in the form of a command menu and definitions of operations) than did usersof the general command vocabulary. However, users ofthe specific vocabulary appeared to take more time actively considering options before deciding to consult HELP. These strategy differences were reflected in users memory for the commands and the task operations 2 weeks later. In addition, the learning strategies adopted were dependent on users predispositions as ...

Using Structural Descriptions of Interfaces to Automate the Modelling of User Cognition

One approach to user modelling (Barnard et al., 1988) involves building approximate descriptions of the cognitive activity underlying task performance in human-computer interactions. This approach does not aim to simulate exactly what is going on in the users head, but to capture the salient features of their cognitive processing. The technique requires several sets of production rules. One set maps from a real-world description of an interface design to an internal theoretical description. Other rules elaborate the theoretical description, while further rules map from the theoretical description to properties of user behaviour. This paper is concerned primarily with the first type of rule, for mapping from interface descriptions to theoretical description of cognitive activity. Here we show how structural descriptions of interface designs can be used to model user tasks, visual interface objects and screen layouts. Included in our treatment are some indications of how properties of cognitive activity and their behavioural consequences can be inferred from such structural descriptions. An expert system implementation of the modelling technique has been developed, and its structure is described, together with some examples of its use in the evaluation of HCI design scenarios.

Dialogue Design: Characteristics of User Knowledge

Publisher Summary This chapter discusses some of the characteristics of the knowledge and understanding that users call upon in learning to use interactive systems. To learn to use a complex interactive system, people have to acquire a good deal of new knowledge. They must attempt to organize and to structure their knowledge so that it conforms to the requirements of the system. The chapter reviews findings from observational studies of novices learning to use computer systems. The results illustrate the complexity and diversity of human learning; users call upon many sources of information and represent their knowledge in many ways. Both general and specific hypotheses concerning the nature of user knowledge are drawn. The chapter explains some of these hypotheses by reference to a number of experimental studies of interface dialogue. Taken as a whole, the results suggest that analyses of the ease of use of a system must take into account not only the nature of the interface dialogue itself but also the detailed cognitive context in which a particular exchange occurs. The cognitive context of an interaction includes the general cognitive demands imposed by the system, information extracted from the wider task environment, the specific question or problem motivating the exchange, and the cognitive strategies mobilized in the course of learning and use.

Learning and remembering interactive commands

There is a rich and expanding folklore concerning the consequences of inappropriate naming of computer commands. The problems are particularly acute for occasional users of interactive systems who may be unfamiliar with the jargon of computing. While “naming” has long been of interest to philosophers, linguists and psychologists [2], there is little systematic research on the psychological processes involved in the understanding and acquisition of the vocabularies of interactive computer systems.n Since the names for interactive commands tend to be drawn from the wider vocabulary of natural language, occasional users are faced with the task of understanding, learning and remembering new meanings for the words.

On defining requirements for interaction

Requirements that involve the usability of systems can be properties of interactions rather than systems alone. This proposition is demonstrated by means of four examples. The authors suggest that a notation like CSP (communicating sequential processes) may be used to provide a framework for considering different modeling approaches. Interaction requirements that relate to multiwindowed systems, walk up and use systems, and dynamic systems such as power stations are considered. It is shown how models provide different representations to which advice from the different disciplines of human computer interaction may be applied.<<ETX>>