Systems and methods for synthesizing an image of the face by a head-mounted display (HMD), such as an augmented reality device, are disclosed. The HMD may be able to observe only a portion of the face with an inward-facing imaging system, e.g., the periocular region. The systems and methods described herein can generate a mapping of a conformation of the portion of the face that is not imaged based at least partly on a conformation of the portion of the face that is imaged. The HMD can receive an image of a portion of the face and use the mapping to determine a conformation of the portion of the face that is not observed. The HMD can combine the observed and unobserved portions to synthesize a full face image.