Cognition at all levels

The cognitive revolution in psychology has come a long way since the early work of Noam Chomsky, George Miller and Donald Broadbent. In the 1970s it brought us cognitive science, and more recently cognitive neuroscience has begun to emerge as an identifiable discipline in its own right.

Mark Ashcraft's Fundamentals of Cognition is the most traditional of the books under review. It provides a standard introduction to cognitive psychology for undergraduates. Unfortunately traditional is a synonym for dated. There are few citations to work from the present decade. While much of the groundwork of cognitive psychology was laid 30 or more years ago (and reference to such work is essential), the failure to reference recent work raises two problems. First, and from a student's perspective, the text fails to convey a sense of excitement. All the main questions appear to have been dealt with decades ago and the field appears fallow.

Perhaps more seriously from a teacher's perspective, there are some startling omissions. To take just one example, the most recent reference to the work of Chomsky is from 1968. Ashcraft fails to present important developments in the psychology of language, such as the theory of universal grammar and the debate over nativism. Omissions of similar import occur throughout the text.

Cognition: Exploring the Science of the Mind by Daniel Reisberg is a text with a similar, but more modern, agenda. Reisberg presents a comprehensive coverage of perception, attention, memory, knowledge, language, reasoning and problem solving. The breadth of coverage is greater than that of Ashcraft and the citations are to significantly more recent work. However, the level is also more advanced and it is perhaps unfair to attempt a direct comparison of the two. The advanced level of Reisberg's text is reflected by the inclusion of relatively few pedagogical aids, such as boxed text, section summaries and demonstration experiments. But the book is readable and would serve well as an accompaniment to an advanced undergraduate course in cognitive psychology.

This generally positive appraisal of Reisberg's work is tempered by the fact that there are already a number of very adequate, up-to-date, cognitive psychology texts on the market. Reisberg's text has just two distinguishing features: the integration of neuro-psychological issues into relevant chapters and the inclusion of a necessarily speculative chapter on consciousness. These features may make the book attractive for a new course, but they do not constitute a reason for lecturers in existing courses to switch to it.

Michael Dawson's Understanding Cognitive Science is an altogether different book. Cognitive science, as distinct from cognitive psychology, is notoriously difficult to define. While most cognitive scientists know cognitive science when they see it, the boundaries of the field are unclear and few can verbalise just what constitutes it.

Dawson tackles this issue head on, arguing that cognitive science is defined by its methods, rather than its subject matter and that the defining method is, following David Marr, the description of mental processes at three levels: the computational level, the algorithmic level and the implementational level.

This is not a novel hypothesis, but Dawson's use of the tri-level hypothesis to drive a cognitive science text is admirable. It stands in stark contrast to most other cognitive science texts that focus, incorrectly in Dawson's view, on aspects of cognitive competence at the expense of the methods by which such aspects are investigated.

Dawson's book is very readable and will suit advanced-level undergraduates or postgraduate cognitive science students with a speciality in one of the contributing disciplines. The book goes beyond being merely a text, however. Dawson appears to have a secondary objective: to change the way cognitive scientists think about their discipline. In particular, he argues convincingly that the tri-level hypothesis can be applied to both connectionist and classical cognitive science, and as such, that the tri-level hypothesis bridges the principal chasm that stands to divide cognitive science. This is a book which I recommend not just as a text, but as essential reading for practising cognitive scientists.

The most recent chapter in the cognitive revolution is that of cognitive neuroscience - the attempt to integrate neurological knowledge and methods with cognitive psychological knowledge and methods in our understanding of the brain, the mind, and the relation between the two. This is a new and rapidly developing field, and, in producing Cognitive Neuroscience: The Biology of the Mind , Michael Gazzaniga, Richard Ivry and George Mangun have something of a world exclusive. The book is unique in providing in a single volume an introduction to neuroanatomy, neurophysiology and neuropsychology. The organisation is primarily determined by the traditional facets of cognition - perception, attention, memory, language, motor control and executive functions - but chapters are also devoted to issues more normally associated with neurology, such as cerebral lateralisation and specialisation, and development and plasticity.

Highlights of this offering include clear yet detailed text, coupled with engaging writing, case studies, interviews with leading figures in the field and the inclusion of a multitude of colour illustrations. All of these add to the text's readability. Indeed, it sets a high standard for future cognitive neuroscience texts. It is therefore an ideal primary text for any undergraduate course in cognitive neuroscience.

Its suitability for postgraduate courses is less clear. It provides valuable background material and pointers to the literature, but postgraduates will need to spend more time pursuing the suggested readings given in each chapter. Perhaps though, this is how postgraduates should use all textbooks.

Richard Cooper is lecturer in psychology, Birkbeck College, University of London.