Practice and incentive motivation in recognition of inverted faces

In each of three experiments, participants received successive daily practice sessions on the task of recognizing inverted faces. In all practice sessions, an initial study series of 25 inverted faces was followed immediately by a test series of 17 pairs of inverted faces. Each test pair comprised a face from the study series and a new face. Completely new sets of faces were used in each session. Recognition of inverted faces did not improve across sessions in Exp. 1 but did improve in Exps. 2 and 3. Unlike Exp. 1, Exps. 2 and 3 employed an explicit incentive for improved performance. These results show that sufficiently motivated participants can become quite proficient at recognizing inverted faces. Implications of the results for the role of expertise at recognition in producing the inversion effect are discussed.