Both anxiety and depression have been linked with attention and executive deficits, yet the nature of these deficits and their clinical implications remain unclear. Chapter 1 reviews existing theories and findings from these literatures, along with key limitations of the existing research. Chapter 2 examines relations between worry, Generalized Anxiety Disorder (GAD), and working memory capacity (WMC). Results revealed that reduced WMC was associated with symptoms of GAD and elevated levels of worry, both cross-sectionally and prospectively. In contrast, WMC was not associated with depression. These findings suggest that reduced WMC may play a role in the etiology of excessive worry. Chapter 3 examines executive deficits associated with current and past symptoms of Major Depressive Disorder (MDD). Results revealed that current (MDD) symptoms were associated with deficits in inhibition – nevertheless, these deficits were not unique to depression, but were also associated with measures of state mood and current GAD symptoms, suggesting that they may simply be a by-product of general distress. In contrast, set-shifting deficits were uniquely associated with past MDD symptoms, suggesting that these deficits may reflect an ongoing vulnerability to depression. Chapter 4 examines individual differences in inattentional blindness (IB). Across two independent samples, results revealed that attention and executive abilities (e.g., multiple object tracking skills, WMC) did not predict whether participants noticed the unexpected stimulus, but levels of anxiety and depression did. Specifically, results revealed a significant three-way interaction between worry, anxious arousal, and anhedonic depression predicting IB. Chapter 5 discusses a number of important directions for future research on attention and executive deficits associated with dimensions of anxiety and depression
