杏吧原创

THIS year, University College London made the world鈥檚 first professor of neuroaesthetics. In recent decades, he has used brain imaging techniques to pioneer the modern study of visual perception, as Nobel laureate Eric Kandel writes on the jacket of , and his earlier books include an impressive written (in French) with the painter Balthus. His new book aims to bring these two areas of expertise together by applying the neuroscience of creativity to artists, writers and composers such as Michelangelo, Dante and Wagner, and so it arouses high expectations. Unfortunately, the result is disappointing.

Consider his treatment of C茅zanne, a painter celebrated for subtle colouring of natural scenes. Near the beginning of the book, Zeki quotes C茅zanne as saying: 鈥淐olour has a logic and the artist must always obey that logic, never the logic of the brain.鈥� Zeki disagrees: 鈥淭here is, in fact, no logic to colour except the logic of the brain.鈥� Yet much later, in an admiring chapter on C茅zanne, he remarks: 鈥淭hough knowing nothing about the visual brain [C茅zanne] was nevertheless remarkably insightful into its workings.鈥� How, then, does C茅zanne鈥檚 understanding of visual perception differ from Zeki鈥檚? If C茅zanne was wrong, why were his insights fruitful? The book never resolves this apparent contradiction.

Zeki subscribes to the argument that colours do not exist independently of the way that our brains perceive them. For example, the brain preserves our perception of colours regardless of lighting conditions, by cleverly keeping constant the ratio of red, green and blue light reflected from an object and from its surroundings. 鈥淎 green surface, for example, remains green whether viewed at dawn, at dusk, or at noon on a cloudy or sunny day,鈥� Zeki writes. Leaves on trees do not appear to change colour with changes in weather. Indeed, he claims 鈥渢here are no colours but constant colours鈥�.

Surely, the truth is more complex. A leaf certainly looks green to us whether in bright sun or shadow 鈥� but it is not the same green. The apples in C茅zanne鈥檚 iconic 1873 painting Green Apples (below) contain at least half a dozen identifiable shades of green carefully contrived by the artist. Moreover, the greens change appearance under natural and artificial light. Anyone who has tried to choose a paint colour from a house decorator鈥檚 colour chart knows how sensitive the brain鈥檚 perception of colour is to light and shadow. What looked right on the chart often looks wrong on the wall.

Zeki鈥檚 theory of perception, unless I have misunderstood him, is that reality derives from the brain creating synthetic concepts, such as 鈥済reen鈥�, 鈥渂eauty鈥� and 鈥渓ove鈥�, from sensory data. He thus stands in opposition, he says, to the idealist theory of the ancient Greek thinker Plato, who banished artists from his model republic on the grounds that art can gain only partial access to reality through observation and thought.

The 鈥渟plendour and the misery鈥� of his title (borrowed from the novelist Balzac) refer to the brain鈥檚 effortless ability to generate concepts, set against the failure of daily experience to live up to these concepts. Creativity is the product of this conflict, writes Zeki, and a great creator is energised by the desire for a perfect match between art and life. 鈥淚t is this great insufficiency that drives him on,鈥� the painter Lucian Freud once wrote. The creator鈥檚 inevitable frustration is why Michelangelo, C茅zanne and others left so many of their works unfinished, according to Zeki.

鈥淎 great creator desires a perfect match between art and life鈥�

The last third of the book tackles concepts of love. Zeki has published much on neural correlates of love and includes several brain scans from his journal articles. They display particular sites in the brain that are activated when a subject views pictures of a loved partner; they also show that romantic love and maternal love activate different sites, though with considerable areas of overlap. Intriguing as they are, however, the scans cannot make the case for an inherited brain concept of 鈥渦nity-in-love鈥� found throughout the world鈥檚 literature and art, as Zeki maintains. To write of Act 1 of Wagner鈥檚 Tristan and Isolde that 鈥渢his love potion is perhaps best understood metaphorically, as a concept unleashed in the protagonists鈥� brains鈥� sounds more ridiculous than sublime to my ears, and hardly scientific.

For all Zeki鈥檚 evident scientific expertise and love of the arts, he does not really succeed in using each to illuminate the other.