This research explores the effect of emotional states on visual detection. Previous research has shown that emotional states characterized by an intolerance of uncertainty, such as anxiety, can affect performance on visual detection tasks. It is unclear, however, to what extent these effects are a result of increased perceptual ability, a decisional bias, or both. The present study used signal detection theory to determine whether uncertain emotional states affect perceptual discriminability and/or decisional bias. In 2 experiments, an anxious, angry, or calm emotional state was induced, and participants were asked to identify which of a series of noisy images contained an embedded target image. The target images were either faces or houses. Emotional state had no effect on decisional bias for either target, but the ability to detect a face was higher for anxious participants. No effect on discriminability was found for houses. These results suggest that emotional state can change perceptual discriminability, but that this change may be limited to certain stimulus classes.