Guillaume-Benjamin-Amand Duchenne (de Boulogne) (September 17, 1806, in Boulogne-sur-Mer – September 15, 1875, in Paris) was a French neurologist who revived Luigi Galvani's research and greatly advanced the science of electrophysiology. The era of modern neurology developed from Duchenne's understanding of neural pathways and his diagnostic innovations including deep tissue biopsy, nerve conduction tests (NCS), and clinical photography. This extraordinary range of activities (mostly in the Salpêtrière) was achieved against the background of a troubled personal life and a generally indifferent medical and scientific establishment.

Neurology did not exist in France before Duchenne and although many medical historians regard Jean-Martin Charcot as the father of the discipline, Charcot owed much to Duchenne, often acknowledging him as "mon maître en neurologie" (my master in neurology).McHenry, p. 282: "His interest in neurology, which was slow in evolving, was largely inspired by Duchenne, whom Charcot called his "master in neurology." The American neurologist Joseph Collins (1866–1950) wrote that Duchenne found neurology "a sprawling infant of unknown parentage which he succored to a lusty youth." His greatest contributions were made in the myopathies that came to immortalize his name, Duchenne muscular dystrophy, Duchenne-Aran spinal muscular atrophy, Duchenne-Erb paralysis, Duchenne's disease (Tabes dorsalis), and Duchenne's paralysis (progressive bulbar palsy). He was the first clinician to practise muscle biopsy, with an invention he called "l'emporte-pièce" (Duchenne's trocar).This device was described by Gowers as 'Duchenne's histological harpoon,' and by others as a 'miniature harpoon' - metonymy that alluded to his parentage by the sea. In 1855, he formalized the diagnostic principles of electrophysiology and introduced electrotherapy in a textbook titled De l'electrisation localisée et de son application à la physiologie, à la pathologie et à la thérapeutique. A companion atlas to this work, the Album de photographies pathologiques, was the first neurology text illustrated by photographs. Duchenne's monograph, the Mécanisme de la physionomie humaine – also illustrated prominently by his photographs – was the first study on the physiology of emotion and was highly influential on Darwin's work on human evolution and emotional expression.

Biography

Guillaume-Benjamin Duchenne descended from a long line of mariners who had settled in the Boulogne-sur-Mer region of France. In opposition to his father's wishes that he become a sailor, and driven by a fascination with science, Duchenne enrolled at the University of Douai where he received his Baccalauréat at the age of 19. He then trained under a number of distinguished Paris physicians including René-Théophile-Hyacinthe Laënnec (1781–1826) and Baron Guillaume Dupuytren (1777–1835) before returning to Boulogne and setting up in practice there. Duchenne married a local woman, and, following the birth of their son, his wife died. This resulted in a lengthy period of personal difficulties for Duchenne with his family and in a prolonged estrangement from his son (who later followed Duchenne into medical practice) and they were only reunited towards the end of his life.

In 1835, Duchenne began experimenting with therapeutic "électropuncture" (a technique recently invented by François Magendie and Jean-Baptiste Sarlandière by which electric shock was administered beneath the skin with sharp electrodes to stimulate the muscles). After a brief second marriage, Duchenne returned to Paris in 1842 in order to continue his medical research. Here, he did not achieve a senior hospital appointment, but supported himself with a small private medical practice, while daily visiting a number of teaching hospitals, including the Salpêtrière psychiatric centre. He developed a non-invasive technique of muscle stimulation that used faradic shock on the surface of the skin, which he called "électrisation localisée" and he published these experiments in his work, On Localized Electrization and its Application to Pathology and Therapy, first published in 1855. A pictorial supplement to the second edition, Album of Pathological Photographs (Album de Photographies Pathologiques) was published in 1862. A few months later, the first edition of his now much-discussed work, The Mechanism of Human Physiognomy,Mécanisme de la Physiognomie Humaine, Ist Edition 1862-3; 2nd Edition, published Paris, J.B. Baillière, 1876 was published. Were it not for this small, but remarkable, work, his next publication, the result of nearly 20 years of study, Duchenne's Physiology of Movements,Physiologie des mouvements démontrée à l'aide de l'expérimentation électrique et de l'observation clinique, et applicable à l'étude des paralysies et des déformation, published in 1867 his most important contribution to medical science, might well have gone unnoticed.

Despite his unorthodox procedures, and his often uneasy relations with the senior medical staff with whom he worked, Duchenne's single-mindedness obtained him an international standing as a neurologist and researcher. He is counted as one of the developers of electro-physiology and electro-therapeutics, and he also showed that smiles resulting from true happiness not only utilize the muscles of the mouth but also those of the eyes: such "genuine" smiles are known as Duchenne smiles in his honor. He is also credited with the discovery of Duchenne muscular dystrophy. Duchenne died in 1875, after several years of illness. He was never elected to the French Academy of Sciences nor did he belong to a French university.

The Mechanism of Human Facial Expression

Influenced by the fashionable beliefs of physiognomy of the 19th century, Duchenne wanted to determine how the muscles in the human face produce facial expressions which he believed to be directly linked to the soul of man. He is known, in particular, for the way he triggered muscular contractions with electrical probes, recording the resulting distorted and often grotesque expressions with the recently invented camera. He published his findings in 1862, together with extraordinary photographs of the induced expressions, in the book Mecanisme de la physionomie Humaine (The Mechanism of Human Facial Expression, also known as The Mechanism of Human Physiognomy).

Duchenne believed that the human face was a kind of map, the features of which could be codified into universal taxonomies of mental states; he was convinced that the expressions of the human face were a gateway to the soul of man. Unlike Lavater and other physiognomists of the era, Duchenne was skeptical of the face's ability to express moral character; rather he was convinced that it was through a reading of the expressions alone (known as pathognomy) which could reveal an "accurate rendering of the soul's emotions".Duchenne, Mecanisme, part 3, 130-1, trans. Sobieszek. He believed that he could observe and capture an "idealized naturalism" in a similar (and even improved) way to that observed in Greek art. It is these notions that he sought conclusively and scientifically to chart by his experiments and photography and it led to the publishing of The Mechanism of Human Physiognomy in 1862The publication history of Duchenne's Mécanisme is complex and to a degree uncertain.

It was published over the course of 1862 and possibly into 1863. (also entitled, The Electro-Physiological Analysis of the Expression of the Passions, Applicable to the Practice of the Plastic Arts. in French: Mécanisme de la physionomie humaine, ou Analyse électro-physiologique de l'expression des passions applicable à la pratique des arts plastiques), now generally rendered as The Mechanism of Human Facial Expression. The work compromises a volume of text divided into three parts: General Considerations, A Scientific Section, and An Aesthetic Section.

These sections were accompanied by an atlas of photographic plates. Believing that he was investigating a God-given language of facial signs, Duchenne writes:

In the face our creator was not concerned with mechanical necessity. He was able in his wisdom or – please pardon this manner of speaking – in pursuing a divine fantasy … to put any particular muscles into action, one alone or several muscles together, when He wished the characteristic signs of the emotions, even the most fleeting, to be written briefly on man's face. Once this language of facial expression was created, it sufficed for Him to give all human beings the instinctive faculty of always expressing their sentiments by contracting the same muscles. This rendered the language universal and immutable.Duchenne, Mecanisme, part I, 31; Cuthbertson trans., 19.

Duchenne defines the fundamental expressive gestures of the human face and associates each with a specific facial muscle or muscle group. He identifies thirteen primary emotions the expression of which is controlled by one or two muscles. He also isolates the precise contractions that result in each expression and separates them into two categories: partial and combined. To stimulate the facial muscles and capture these "idealized" expressions of his patients, Duchenne applied faradic shock through electrified metal probes pressed upon the surface of the various muscles of the face.

Duchenne was convinced that the truth of his pathognomic experiments could only be effectively rendered by photography, the subject's expressions being too fleeting to be drawn or painted. "Only photography," he writes, "as truthful as a mirror, could attain such desirable perfection."Duchenne, Mecanisme, part I, 65; Cuthbertson trans., 36. He worked with a talented, young photographer, Adrien Tournachon, (the brother of Felix Nadar), and also taught himself the art in order to document his experiments.Although Tournachon contributed some of the negatives for the scientific section, most of the photographs in this section, and all eleven plates corresponding to the aesthetic section, were made by Duchenne. From an art-historical point of view, the Mechanism of Human Physiognomy was the first publication on the expression of human emotions to be illustrated with actual photographs. Photography had only recently been invented, and there was a widespread belief that this was a medium that could capture the truth of any situation in a way that other mediums were unable to do.

Duchenne used six living models in the scientific section, all but one of whom were his patients. His primary model, however, was an "old toothless man, with a thin face, whose features, without being absolutely ugly, approached ordinary triviality."Duchenne, Mechanism, part 2, 6; Cuthbertson trans., 42 Through his experiments, Duchenne sought to capture the very "conditions that aesthetically constitute beauty."Duchenne, Mecanisme, part 2, 8; Cuthbertson trans., 43. He reiterated this in the aesthetic section of the book where he spoke of his desire to portray the "conditions of beauty: beauty of form associated with the exactness of the facial expression, pose and gesture."Duchenne, Mecanisme, part 3, 133; Cuthbertson trans., 102 Duchenne referred to these facial expressions as the "gymnastics of the soul". He replied to criticisms of his use of the old man by arguing that "every face could become spiritually beautiful through the accurate rendering of his or her emotions", and furthermore said that because the patient was suffering from an anesthetic condition of the face, he could experiment upon the muscles of his face without causing him pain.

Aesthetics and the narrative setting