Figure 15: Mediation, mental concentration 1854 - 1856

"Figure 15: Mediation, mental concentration" is a photographic print by Guillaume Benjamin Amand Duchenne from his 1862 book *Mécanisme de la Physionomie Humaine*, or *The Mechanism of Human Facial Expression*. Duchenne, a French neurologist, used electrical stimulation to isolate and photograph different facial muscles and their effects on expression. This particular image depicts a man with a focused and contemplative expression, demonstrating Duchenne's interest in understanding the physiological basis of emotion. The image is part of a series of studies that revolutionized the understanding of facial expressions and influenced artists and scientists alike. The print, now housed at the Metropolitan Museum of Art, remains a powerful testament to Duchenne's pioneering work in the field of human expression.