Neuroscience Experiments from the 19th Century: Capturing the Human Facial Expression, 1862
Guillaume-Benjamin-Amand Duchenne de Boulogne was curious to determine how the muscles in the human face generate facial expressions that he believed to be directly associated to the soul of man.
Inspired by the fashionable theories of physiognomy of the 19th century, Duchenne conducted experiments involving how to trigger the facial muscles using electrical probes, then recording the distorted and often grotesque expressions caused by this with the contemporary camera. By 1862, he published his findings together with extraordinary photos of the induced expressions, in the book entitled Mecanisme de la physionomie Humaine (The Mechanism of Human Facial Expression, also called as The Mechanism of Human Physiognomy).
Duchenne considered the human face as a kind of map, of which the features could be coded into universal taxonomies of mental states. He also believed that the expressions of the person's face was a gateway to his soul.
"The face of an old man... photographed in stillness."
"The grimace generated is similar to a tic of the face."
"A study of m. frontalis during maximum contraction."
"A photo showing the expressive lines of m. frontalis within a young girl."
"A study of the contraction and the expression generated by the superior portion of m. orbicularis oculi"
"The expression of severity."
"On the right, electrization of m. procerus: severity, aggression. On the left: attention."
"Profound suffering, along with resignation."
"Maximum pain to the point of exhaustion, the head of Christ and memory of love or ecstatic gaze."
"Expression of a painful attention and an attentive gaze."
"Expression proportionally pained."
"Scornful laughter versus scornful disgust."
"The attention captivated by an object that engages lascivious ideas and desires."
"Pain and despair."
"A proposition of this same weeping."
"Expression of mild weeping, pity and feeble false laughter."
"Voluntary withdrawal of the lower lip."
"Expression of Whimpering and false laughter."
"Voluntary lowering of the lower jaw."
"Expression of astonishment, stupefaction, amazement."
"Expression of terror."
"Scene of coquetry."
"Lady Macbeth with a strong expression of cruelty."
“This expression must be that of the damned.”
"Painful weeping and forward looking."
"Nun saying her prayers."
"Lady Macbeth, moderate expression of cruelty."
"Lady Macbeth, ferocious cruelty."
"Faradisation of the frontal muscle."
Contradictory to Lavater and other physiognomists of that period, Duchenne was skeptical of the face's potential to express moral character. He was more convinced that it was reading of the expressions alone (known as pathognomy) that could actually reveal an "accurate rendering of the soul's emotions". He also believed that he could study and capture an "idealized naturalism" in the same (and even improved) way to that observed in Greek art. It is due to these notions that he desired conclusively and scientifically to chart his experiments and photography which led to the publication of his book The Mechanism of Human Physiognomy in 1862, now generally known as The Mechanism of Human Facial Expression.