Emotional Perceptual Training as a Treatment for Social Anxiety: Behavioral and Neural Evidence.

"Participants viewed faces varying in their expression of anger and were asked to identify if the face was angry or neutral via button press. Participants were provided with feedback if their categorization of the face as neutral or angry was correct. Each participant was assigned 4 levels of angry faces based on their decision point of anger detection in faces. Faces were selected based on the closest existing anger morph to the category boundary; for example, a decision point of 40% anger was closest to the 38% anger face, and so the faces used would have been 17%, 31%, 45%, and 59% anger. For this example, responses of neutral to the 31% angry face would be marked as correct, whereas a similar response to the 45% angry face would be incorrect, as it was above their decision point."

Participants viewed faces varying in their expression of anger and were asked to identify if the face was male or female via button press.