By Emma Meyers
Lately, I’ve been making my way through Columbia alum Jonah Lehrer’s science-meets-art book Proust Was a Neuroscientist. In it, Lehrer lauds the many artists, writers, and composers who, through their art, tapped into the human brain in ways modern neuroscientists are only recently discovering. Despite whatever controversy now surrounds Lehrer’s name, the book is anchored on some fascinating ideas, and, while possibly a bit overstated, his claims really set me thinking.
Mostly, I was dismayed by Lehrer’s easy dismissal of the artist Claude Monet in a chapter focusing on Paul Cézanne, a painter whose style developed out of Monet’s Impressionist tradition. In this account, Cézanne takes advantage of the brain’s ability to visualize a scene as a whole – to integrate its disparate and sometimes abstract elements into a single coherent image – and relies on the juxtaposition of bold swaths of color to imply, rather than state outright, the image the viewer sees. Monet, his apparently-less-neuroscientifically-inclined predecessor, merely plays with light to create pretty but simple scenes.
But, in defense of my favorite painter on the Art Hum syllabus, Monet was also a neuroscientist.
The Impressionists’ goal was to depict the world not exactly as it was, but as we see it – our impressions as we move through it. While capturing these impressions involved more than just understanding how sunlight plays on water and grass – Monet brilliantly imbues his paintings with the motion of the breeze and the warmth of the sun – the visual experience is certainly at the forefront of his work. And the light and shadow, which Monet so expertly manipulates in his art, are critical components of how we distinguish objects in a scene. At their core, all of our visual perceptions are built upon the contrasts between light and shadow so that what we’re seeing is an object wholly created by light. Or, to use Monet’s words, “it is only the surrounding atmosphere which gives objects their real value.”
Like all sensory receptors in our bodies, the cells of our retinas have specific receptive fields, specific regions or patterns of stimuli (light, in the case of our eyes) that they respond to. When a stimulus falls in a neuron’s receptive field, it can either be excited (it fires more) or inhibited (it fires less).
Research in the 1950′s showed that the receptive fields of retinal cells are arranged in a concentric circular pattern of contrasting inhibition and excitation called “center-surrounds.” When light falls in the receptive field of the neurons in the center of the configuration, the cells are either excited or inhibited; when it hits the receptive fields of the outer “surround” cells, it will have the opposite effect. Because the inhibition and excitation of each center-surround unit can cancel each other out when it’s uniformly drenched in light, this arrangement means the bulk of the visual information that reaches our brain encodes edges – abutting contrasts in lightness or darkness (for a great explanation with visuals, watch this video of neuroscientist Margaret Livingstone). Our visual world, then, is constructed primarily of borderlines, the contours between light of different intensities; we can only understand what we’re looking at through higher level processing and integration of this crude light information.
Monet clearly expresses this total reliance on light in his art. Take, for instance, these three paintings from a series of the façade of the Rouen Cathedral:
All three of these paintings are of the same face of the building viewed from the same spot at different times of day. The church itself has very little mass – it is blurry and airy, no real detail. These paintings are, however, rich with the contours of light and shadow that define its façade. In the first two images, the recessed doorway and round window above it are defined not by line, but by the gradient of light to dark. In the third rose-tinted one, the columns at the base of the façade are not columns at all, but swaths of bright paint next to darker colors. Just as our retinas would abstract the edges from a scene like this, the gross lines between different levels of illumination, Monet recreates the scene in broad strokes and soft gradations. While obviously based on a simplified visual system – Monet, after all, was not actually a neuroscientist – these paintings manage to acknowledge how we see on the most fundamental level.
For more on the neuroscience of art, watch this awesome lecture by neuroscientist Margaret Livingstone. It’s long, but worth it.