The formulation of paints and the way they are deposited on a support are at the origin of the effects perceived by our eyes and then our brains. By combining the physico-chemical considerations developed in previous lectures with those arising from research in the field of neurobiology, we are now seeing the emergence of a new interdisciplinary approach to works of art. The aim of this lecture is to describe some of the issues involved.
The question of physiological color perception cannot be dissociated from the analysis of transparency effects generated by the addition of certain compounds (the abundant binder in Leonardo da Vinci's glazes or, in some of Rembrandt's paintings, the addition of wheat flour) or neighborhood effects such as those described in 1839 by Michel Eugène Chevreul in his Loi du contraste simultané des couleurs : a color is influenced by its neighbors. What's more, certain illnesses can profoundly alter perception. Some artists have suffered from vision problems that have altered the way they create their works. As soon as Claude Monet suffered from cataracts, his works darkened and some colors disappeared. The multiple versions of Les Nymphéas between 1910 and 1923 bear witness to this phenomenon. In 1900, before the onset of his cataract, the forms are clear, with multiple details and varied colors. Subsequently, his paintings take on tints that become more accentuated in reds and yellows. Details fade. Realizing in 1915 that his perception of colors was distorted, the artist explained that reds appeared "muddy" to him.
Today, work in the neurosciences is also beginning to clarify the neural bases of aesthetic pleasure, leading to studies that aim to better understand how we can appreciate a fake work and its copy differently, or what the brain activity of subjects is as they judge the beauty (affective and aesthetic judgment) and luminosity (perceptual judgment) of paintings presented simultaneously.
