“Visual Insights: What Art Can Tell Us About the Brain”
Professor Margaret Livingstone, Tuesday 22 October 2013.
For the second Frank Davis memorial lecture of 2013, the Courtauld community and guests were given a privileged glimpse into the workings of our own visual processing by Margaret Livingstone of Harvard Medical School. Applying developments in neurobiology to a study of pictorial reception, Professor Livingstone’s research in recent years has explored the evidence that artists also spend a lot of time trying to figure out how we see. Along with plentiful information on the finely tuned operation of neurons within the visual pathway, it was the interactive experience – facilitated by red-green cinema specs – which cemented for the audience the evidence of how the brain processes retinal responses to pictures, faces, and pictures of faces.
Those who had turned up to hear the big neurological reveal on the secret of the Mona Lisa’s smile were not to be disappointed, but first we needed the basic picture. Through diagrams illustrating the opposing actions of ganglion cells on the retina, which can both fire or repress signals depending on the area receiving light, Professor Livingstone demonstrated the dominant principles of luminance and contrast at the base line of vision. This evidence helps to access the employment of light and shadow throughout the history of art, from the uniform brilliance of haloes in a Duccio altarpiece to Impressionist experiments with movement created by subtle variants in light value. Such effects were further explained by a diagram of the primate brain showing the division of two distinct functions: the ‘what system’ which has developed to recognise objects, colour and faces; and the ‘where system’ which takes the more general role of detecting spatial relations of depth, distance, figure/ground, and movement. These separate functions are behind the puzzling effects of optical illusions and those red-green patterns familiar from optical examinations; and, as illustrated with works by Monet and Mondrian, are expertly manipulated by visual artists. Correspondingly, we were shown how it could be the difference in acuity between central and peripheral vision which is behind the enigmatic smile of the Mona Lisa.
Returning to the visual peculiarities of artists themselves, the lecture concluded with an intriguing insight into the properties of stereovision and the likelihood of ocular misalignment or of dyslexia as a contributing factor in the artist’s particular facility in translating volumes into flat pictures. A graph based on Rembrandt’s depictions of his own eyes in a series of painted and etched self-portraits provided a convincing argument in favour of the research, as of Professor Livingstone’s parting comment; namely, that ‘if you can make a graph of the unlikeliest thing, you can get published’. The background to this science and its application to artistic vision are explained in Margaret Livingstone’s book, Vision and Art (2002), available in the Courtauld Library.