8A wealth of data from behavioral, neuroimaging, pharmacological, and genetic studies has served to highlight the centrality of attentional processes in our understanding of anxiety and depression. Aberrant deployment of attention, particularly in relation to emotional information, occupies a pivotal position in many of the contemporary models of these disorders in which it is considered a causally relevant, proximal illness process. This view suggests that interventions that modify the habitual deployment of attention to emotional information should impact upon illness expression. In the present article, we will review the evidence that emotional attention may be modified in both experimental and clinical settings. In doing so, we will highlight the data that demonstrate that this modification may be achieved by targeting at least two distinct control mechanisms. Finally, we will consider the implications of this work, particularly with regard to future research and treatment development.
What Evidence Links Abnormalities of Emotional Attention and the Emotional Disorders?Both depression and anxiety have been associated with biases in the processing of emotional information; patients with these disorders habitually interpret, attend to, and/or remember information in a more negative manner than do nonclinical control participants (Mathews & MacLeod, 2005). Cognitive theorists suggest that these habits of thought are causal factors in the etiology and maintenance of the disorders (Beck, 1976;Mathews & Mackintosh, 1998;Mathews & MacLeod, 2005;Mogg & Bradley, 1998;Williams, Watts, MacLeod, & Mathews, 1997). Anxiety has particularly been associated with a tendency to attend to threatening information-a phenomenon that has been termed negative attentional bias (see Figure 1 for a summary of the tasks commonly used to assess attentional bias; Fox, Russo, & Georgiou, 2005;MacLeod, Campbell, Rutherford, & Wilson, 2004;Mathews & MacLeod, 1985;Williams, Mathews, & MacLeod, 1996). Recent work, much of it discussed in the body of this article, has employed simple computer-based tasks in order to induce attentional biases in nonclinical populations (for reviews, see MacLeod, Koster, & Fox, 2009;Mathews & MacLeod, 2002). Critically for psychopathology, these studies provide direct support for a causal role of attention in anxiety by demonstrating that inducing a negative attentional bias can lead to symptoms of anxiety in nonclinical participants.In depression, the most consistent cognitive abnormalities were initially described in measures of memory (Gilboa-Schechtman, Erhard-Weiss, & Jeczemien, 2002;Mathews & MacLeod, 2005;Ridout, Astell, Reid, Glen, & O'Carroll, 2003;Williams et al., 1997); however, there has been increasing interest in the possibility that attentional biases may exist in this disorder as well. Specifically, depression has been shown to be associated with a tendency to attend to the spatial location of negative words (Bradley, Mogg, & Lee, 1997;Donaldson, Lam, & Mathews, 2007;Mogg, Bradley, & Williams, 19...