The Expression of the Emotions in Man and Animals a greater role for the higher cortical centres in the regulation of the emotional response, and touches on the theme of gender differences in emotional expression, anticipating the approach of sociologist Norbert Elias in "The Civilizing Process". In 1905, Sir Arthur Mitchell, a psychiatrist who had served as William A.F. Browne's deputy in the Scottish Lunacy Commission, published "About Dreaming, Laughing and Blushing", bridging some of Darwin's concerns with those of psychoanalysis. Freud's early publications on the symptoms of hysteria (with his influential concept of unconscious emotional conflict) acknowledged debts to Darwin's work on emotional expressionand Darwin's impact on psychoanalysis
The Expression of the Emotions in Man and Animals with engravings of the Darwin family's domestic pets by the zoological illustrator T. W. Wood as well as work by the artists Briton Rivière, Joseph Wolf and A.D. May. It also included portraits by the Swedish photographer Oscar Rejlander (1813–1875), anatomical diagrams by Sir Charles Bell (1774–1842) and Friedrich Henle (1809–1885), as well as illustrational quotations from the "Mécanisme de la physionomie humaine" (1862) by the French neurologist Duchenne de Boulogne (1806–1875). As a result of his domestic psychology experiments, Darwin reduced the number of commonly observed emotions from Duchenne's calculation of more than sixty facial expressions, to just six