Top-down and bottom-up factors in threat-related perception and attention in anxiety.

Anxiety is characterized by the anticipation of aversive future events. The importance of prestimulus anticipatory factors, such as goals and expectations, is well-established in both visual perception and attention. Nevertheless, the prioritized perception of threatening stimuli in anxiety has been attributed to the automatic processing of these stimuli and the role of prestimulus factors has been neglected. The present review will focus on the role of top-down processes that occur before stimulus onset in the perceptual and attentional prioritization of threatening stimuli in anxiety. We will review both the cognitive and neuroscience literature, showing how top-down factors, and interactions between top-down and bottom-up factors may contribute to biased perception of threatening stimuli in normal function and anxiety. The shift in focus from stimulus-driven to endogenous factors and interactions between top-down and bottom-up factors in the prioritization of threat-related stimuli represents an important conceptual advance. In addition, it may yield important clues into the development and maintenance of anxiety, as well as inform novel treatments for anxiety.