Perceptual Neuroscience
Full Title: Perceptual Neuroscience: The Cerebral Cortex
Author / Editor: Vernon B. Mountcastle
Publisher: Harvard University Press, 1998
Review © Metapsychology Vol. 4, No. 35
Reviewer: Anthony Dickinson, Ph.D.
Posted: 9/1/2000
In his attempt to bring together the breadth of knowledge required for the determination of how brain cortical operations underlay perceptual experience, Mountcastle succeeds in providing a scholarly yet accessible volume of relevant material. It does not, however, include a systematic overview of our understanding of the cortex throughout the evolution of the neurosciences. Reading the book from cover to cover in chapter order may prove difficult for those lacking familiarity with the basic principles of neuroscience (c.f.: Kandel & Schwartz; John G. Nicholls et al, for example), the general reader finding this to be a tome of high lexical density which requires an extensive neuropharmacological vocabulary. I would have organized the chapters somewhat differently, and/or cross-referenced chapters for content to help guide the more naive reader. Mountcastle provides no direct answer to the question of what the intrinsic function of the cortex is, but promotes its exploration from a dynamic systems stance, with a view to determining how “a distributed system highlights the dynamic neural representation of one, rather than another, sensory event”.
Prior to presenting the detailed microstructure of the cerebral cortical tissues, Mountcastle provides an extensive introduction to comparative brain morphology (perhaps unnecessarily long for this volume). Although a very appropriate context to have set in the light of the ontogenetic developmental chapters to come, much of the material contained in chapter 2 is better covered elsewhere (e.g., Pearce, 1987; Dunbar, 1998).
Chapter 6 finally introduces the reader to their first taste of the neural substrate dynamics core to this monograph’s principal thesis. Using the hippocampus as an example of a region known in particular for its neural plasticity, the creation and maintenance of memorial processes (as thought to be effected through LTP and LTD mechanisms) are presented as correlating true causal relationships between identifiable synaptic changes over tine. A fine review is offered here (concise in historical, cytoarchitectonic and neurochemical details) together with a candidate cellular basis for the complex operations of the cortical tissues thought to be involved in learning, memory consolidation, the modulation of novel motor patterns – and – ‘perception itself’?
After some 300 pages, I find myself immensely satisfied and now better informed concerning some of the ‘where’ and ‘what’ questions of perception and the structure of cortical tissues, but the ‘how’ questions and the nature of the intrinsic operations of the neocortex remain unanswered.
An excellent review of EEG history and the account of its physiological basis go no further. What does follow, however, are proposals for finer resolution, and thus enhanced cortical microcircuit functional correlates of cognitive activity, revolving around issues of synchronicity, rhythmicity and coherence, but no clear picture is offered as to how such a distributed neocortical system might generate the more ‘holistic’ central representations of component stimulus features. A surprising omission from his volume was any mention of the recent work involved with multi-electrode arrays (of which Mountcastle is such a staunch advocate in vivo) that grow nerve networks in electrodynamic culture media. Surely as valuable a contribution is to be made from this work as from those cited in the earlier molecular biology sections of his story as presented here. Whether the field will require a technological and/or paradigm-shift prior to solving the binding problem in perceptual neuroscience awaits future developments.
As a compendium of the ‘what’ and ‘where’ of the mammalian, human cortex, this volume is essential reading – a potential review text for post-graduate teaching, and a good example of difficult material being successfully collated. I would have preferred a more coherent continuity between chapters (or better cross referencing between them – how was the author’s original layout, I wonder?) so facilitating the navigation of newcomers through this scholarly tour of a single brain region and its geomorphological terrain. For the neuroscience cognoscenti, this is a book of the kind many of us say that we were going to write, but never did. I am pleased that this text was written. More than simply a review, it nonetheless condenses a literature otherwise requiring the space of several boxes in the office. It is valuable reference volume for research, teaching and laboratory shelves alike.
Dr. A. R. Dickinson, Dept. of Anatomy & Neurobiology, Washington University School of Medicine
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