Three-dimensional digital imaging techniques show a subtle but significant aging-related increase in facial asymmetry, especially in the lower two-thirds of the face, according to the new research by ASPS Member Surgeon Helena O. Using a technique called 3D photogrammetry, Dr. Taylor and colleagues performed detailed scans of the facial surface in volunteers, who ranged in age from four months to 88 years. The researchers then calculated the "root mean square deviation" RMSD to quantify the degree of asymmetry between the two sides of each face. This digital imaging approach enabled the investigators to distinguish very subtle levels of asymmetry -- within a fraction of a millimeter. Facial asymmetry was analyzed in terms of age, and between the upper, middle, and lower thirds of the face.
The ability to recognize facial expressions of emotions has been argued to play an important role in social communication. Recently, there has been a growing interest in the investigation of age-related changes in the ability for facial expression recognition. A majority of the aging-related studies on facial expression recognition utilized photographs of prototypical facial expressions of basic emotions as test stimuli, reporting differential age-related changes in the ability to recognize different emotions.