The summer of 1967 saw what may have been the first ever international symposium devoted explicitly to problems of Attention, when Sanders (1967) arranged a meeting at the Institute for Perception at Soesterberg in the Netherlands. This meeting put the seal of respectability on the prodigal who had been reintroduced to polite psychological society in 1958 by Broadbent, in his book Perception and Communication. Despite an auspicious beginning, research on attention had fallen into disrepute during the out-and-out Behaviourist period.
Since Broadbentâs book work on attention has begun to pour from an ever increasing number of laboratories. It seems a suitable occasion, ten years later, to summarise what we now know, and it is to that task that this monograph is dedicated. It attempts to survey the behavioural research in vision and hearing which throws light on how we share and divert attention, to make some general methodological recommendations, to review current theories, and to provide a guide to the relevant physiological work. As far as possible, work on memory has been omitted. A bibliography of the major work to the spring of 1968 is included.
The early years of modern experimental psychology were marked by a considerable amount of research on attention. The laboratories of Wundt, Titchener, and Helmholtz carried out experiments in the field. For Wundt it was attention which turned perception into apperception, and so played a central role in the account of sensation and perception. Titchener was concerned both with particular researches into such problems as âprior entryâ as a function of attention, and also the more general role of attention in the determination of âsensory clearnessâ in introspective reports. Indeed in his book The Psychology of Feeling and Attention (1903) there is a lengthy systematic listing of those factors which catch the attention and a discussion of their role in perception. These factors include intensity, extension (in space), duration, âcertain qualitative characteristicsâ (by which he seems to have in mind emotionally toned stimuli, for he elsewhere describes them as â⊠intimate, worrying, wicked things âŠâ), repetition, suddenness, movement, novelty, association with ideas already present, accommodation of sense organs and the cessation of the stimulus. As we shall see later, there is surprisingly little that modern work would wish to add to such a list, although the actual definition of the various qualities would be given with rather more precision, and the conceptual framework of the list would differ markedly. In particular, interest would centre on differing probabilities of response categories, rather than on introspective judgments of âsensory clearnessâ. Not surprisingly the all-embracing work of William James likewise had a section on attention, although it compares rather poorly in this case with the experimental precision of Titchener. Attention, for James, was
the taking possession by the mind, in clear and vivid form, of one out of what seem simultaneously possible objects or trains of thought.
Focalisation, concentration of consciousness are of its essence. It implies
withdrawal from some things in order to deal effectively with others, and is a condition which has a real opposite in the confused, dazed, scatterbrained state which in French is called âdistractionâ and âZerstreutheitâ in German.
There was also a considerable body of experimental work devoted to the so-called âspan of attentionâ or âspan of apprehensionâ, by such men as Hamilton and Jevons, work concerned with the question of how many things could be held in the mind simultaneously or could be taken in at a glance. This field of study has had a surprising renaissance in the last five years, and the recent publication by Bakan (1967) of extracts from the original sources now makes them readily available.
It is all the more odd, therefore, to see the way in which research on attention disappeared virtually completely from about 1920 onwards, except for references to span of apprehension experiments, some work of the Gestalt school, and the unfruitful definitions of McDougall (1928),
Attention is merely conation or striving considered from the point of view of its effect upon the cognitive processes.
Otherwise, not until the 1950âs were references to the phenomena again made explicitly by name. One of the first was Broadbentâs paper (1954) Therole of auditory localisation in attention and memory span, and the seal of respectability was finally put upon the field by his book already referred to above. As several authors have remarked, the reason for the disappearance of a field of research as important as it is entertaining (a combination comparatively rare in research topics) was probably due to the methods and conceptual framework within which the early workers investigated it.
It fell into bad odour because of the inability of introspective psychologists to agree with one another, or to provide objective evidence to back their assertions. (Broadbent, 1958, p. 109)
Even the definition adopted by Hebb as late as 1949 would not have caused transports of delight in a Watsonian Behaviourist,
When an experimental result makes it necessary to refer to âsetâ or âattentionâ the reference means, precisely, that the activity that controls the form, speed, strength, or duration of the response is not immediately preceding excitation of the receptor cells alone.
though Hebb himself had described the early work, with some justification, as treating of,
⊠various properties of mind, undefinable and impossible to understand. (op cit.)
It was probably due to the inability of the introspectionist methodology to come to terms with the attack of Behaviourism that attention so nearly disappeared from the scene for a quarter of a century. It is certainly true, when you must depend upon instructions which are impossible to obey, such as âpay attention as strongly you canâ, together with a request for judgments about the relative clarity of sensations and perceptions, that experiments become extremely difficult to control or interpret. Anyone will know this who has tried to repeat even the most straightforward of Titchenerâs experiments, such as the demonstration of âprior entryâ. Furthermore, this approach ruled out the use of animals completely, and therefore further removed attention from the notice of the rapidly growing Behaviourist school. It is interesting to see that this barrier has been the last of all to be overcome, and that only within the last four or five years has the concept of attention appeared once again in the experimental systematic study of animal behaviour.
Berlyne (1960) stated the position well:
The problems of stimulus selection are mostly ones that are just beginning to be taken seriously by behaviour theory. There are good reasons why they had to be neglected in favour of problems of response selection for a long time, but a concerted attack on them will be necessary before behaviour theory is equipped for complex and realistic forms of behaviour, especially in human beings. In the guise of questions about awareness, some of the aspects of stimulus selection figured prominently in the writings of the early, introspective experimental psychologists, but they were shelved when the behaviourist revolution took place, largely because the principal preoccupations of the psychologists of that period masked them. Some aspects of stimulus selection have continued to interest the psychology of perception, which has been dealing with questions of prime importance for behaviour theory but has often been carried on in a language that harks back to the days when psychologists were mainly occupied with conscious experience and consequently does not always dovetail neatly into the terminology favoured by behaviour theorists. During the last ten years, however, efforts to merge the study of perceptual phenomena with behaviour theory have been rapidly increasing and some topics, like exploration and curiosity, that psychologists have never really done much about are being eagerly taken up.
The renaissance of interest in attention seems to be connected with three developments. Firstly, the use of operational definition couched in stimulus-response language has become accepted to a degree which allows us to undercut the difficulties of the appeal to introspection, and to put the âobjectsâ of attention and the process itself on a more âexternalâ or âpublicâ footing, with all the advantages in research which that invariably brings. Secondly, towards the end of the Second World War a number of important problems arose for which answers were required from applied psychologists, and which were, whatever they were called at the time, clearly to do with attention. Communications systems in ships, planes and airtraffic control centres all produced situatio...