Cognitive neuroscience is today perhaps the forefront area of cognitive science. Its expansion owes much to the increased availability of non-invasive methods of recording brain activity such as fMRI (functional magnetic resonance imaging), as well as to developments in more traditional microelectrode recording and lesion techniques. These technologies have allowed researchers to answer increasingly precise questions about brain function and advanced our understanding of the complex neural events that underlie cognitive activity.
The Physiology of Cognitive Processes is a collected volume of papers emanating from a 2001 Royal Society discussion meeting and describes some of the developments in this area. It is not a book to provide a comprehensive coverage of cognitive neuroscience. Instead, contributions are selective and focused on the more recent developments. Furthermore, much of the content is written with a specialist readership in mind. These facts alone make the book a poor point of entry for those new to neuroscience. However, for those with some background understanding of the area, what the book offers is a collection of state of the art research and opinion in the field, much of which is authored by international leaders in cognitive neuroscience.
The book contains a short introduction by the editors followed by 13 authored chapters, two of which provide technical accounts of particular relevance to the functioning of the visual cortex. The first of these two technical accounts presents a review of recent developments in the understanding of neural coding in the visual cortex (Oram et al., chapter 3). The second account reviews the principles and applications of fMRI (Logothetis, chapter 4); this account focuses on the blood flow changes that fMRI measures and how it relates to the underlying neural response that is of most interest.
The remaining 11 chapters describe recent developments on various aspects of cognitive function, and in doing so present something of the range of methods and techniques available to cognitive neuroscience. Much of the book is focused on the brain events underlying basic perceptual functions such as colour vision, vibrotactile discrimination and production of visual saccades. However, some chapters are dedicated to higher cognitive abilities such as familiarity judgements, episodic memory and cognitive control.
Maunsell and Cook's chapter on attention (chapter 7) is a particular highlight of the book. The authors discuss recent work they have conducted looking at the neural changes that occur when attention is directed to a stimulus, and how these changes relate to actual behavioural performance. While attention seems to amplify the neural response produced by a stimulus, the extent of this amplification depends heavily on the particular cortical region. In a motion-detection task, attention produced the greatest modulations in the higher regions of the visual cortex: the ventral intraparietal (VIP) and medial superior temporal (MST) areas. Correspondingly, the lowest modulations were found in the lower region of V1. Perhaps surprisingly, behavioural performance was most highly associated with neural responses in an intermediate visual region, the middle ventral intraparietal area (MT), and not the regions in which attentional modulations were most evident. The authors conclude that while neurons in the higher visual regions were those most affected by attention, they are also sensitive to several forms of visual and extra-retinal information, making them a less reliable basis for detecting simple visual events like motion onset. The authors suggest that the effect of