Review of Visual Attention and Cortical Circuits: J. Braun, K. Christof & J. Davis; MIT Press, 2001; ISBN 0-262-02493-4

Attention and consciousness. These are perhaps benefited from proper divisions of papers into chapthe holy grails of our scientific quest into the mind. ters with section prefaces. Without this, it can often Whereas the latter is so difficult to even define, the be difficult to find a direct relevance amongst the former is somewhat more comprehensible, if not at different articles. least definable. Attention can be considered as the What are some of the major advances in attention process that causes one to better process some research? First, it should be noted that attention important or relevant information at cost of reduced involves the interaction of multiple brain areas. This processing of irrelevant information, as measured by is to be expected of a function that serves to affect accuracy and/or reaction time. Within this formulaalmost all types of behaviour. Through a processtion, at least two types of processes require further analysis, one can decompose attention (or tasks investigation: (1) how attention improves processing involving attentional manipulation) into several subof relevant information, and if it truly does this, and components. For example, Corbetta and Shulman (2) what happens to the processing of unattended (Chapter 1) make a distinction about expectation stimuli. What is attention good for? Where does it signals and attentional modulation. Using event-reoccur? What initiates it, carries it, and terminates it lated fMRI, the researchers show that advanced when it is no longer needed? Finally, how does the information about a visual event can increase activabrain carry out this formidable process? The papers tion in relevant brain areas while reducing activation presented in Visual Attention and Cortical Circuits in irrelevant pathways. This augmentation of relevant attempt to shed light on these important questions. and suppression of irrelevant pathways then interacts The primary goal of the book is to bring together with the incoming visual information to affect perthe many approaches used in attention research, from ception and thus behaviour. This is consistent with a imaging studies, electrophysiological recordings, to number of prominent models of attention, including behavioural experiments and computational modelthe Guided Search Model (Wolfe et al., 1989) and ing. This goal is achieved through the fourteen the biased competition model of Desimone and chapters of the book. Although the Overview chapter Duncan (1995). Such models typically posit the makes an attempt at giving the reader some organizaexistence of a top-down biasing mechanism that tional guidance of the book, the book would have enhances the feature maps that code for the expected