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the brain processes


Visual processing begins in the retina where light is transformed into nerve signals which are sent to the visual cortex at the back of the brain. Information then travels to other parts of the brain where specific functions (facial recognition, spatial processing, emotional response, etc.) are performed. The motor cortex then plans and controls movements which the hand implements.
Brain imaging was first developed for clinical studies of brain damage. The fMRI (functional magnetic resonance imaging) technique uses a powerful magnetic field to detect increased blood flow in specific areas of the brain while the subject is performing a particular task. Could an artist at work be observed in this way? The question had never been addressed before. 
While lying inside the scanner, Humphrey drew from photographs in small sketchbooks. He had 30 seconds  or 1 minute to copy each portrait photograph or abstract design. By comparing the brain activity when copying the designs to that when drawing portraits, the processes exclusive to drawing a face could be seen. Non-artists were also submitted to the same routine. 

 
The images of increased blood flow measured along near horizontal slices were mapped onto an image of the brain. 

John: You don't usually draw that way!

Humphrey: Not in as cramped conditions, but I'm used to drawing in unusual conditions and quite quickly... With the 30 seconds drawings I was really on the spot ­ I had to catch the thing on the wing ­ and that's where I had a bit of practice.
 
Test 1: Areas of brain activation (red & yellow) during the drawing of faces. The lowest brain slice (at about eye-level) is top left, the highest is bottom right. Abstract designs were geometric figures. Test 2: Middle scanned slice. Abstract designs were Korean letters. More tests are required to understand differences with previous scan. 

 
Humphrey Ocean Humphrey showed no activation in the visual cortex, but in more frontal regions, suggesting that he was relying on an abstracted representation of each photograph. He was 'thinking' the portraits.
Non-artist In contrast, the non-artists showed most activation in the posterior region of the visual cortex, indicating that they were 'slavishly copying' the photograph. 
Comparison of Humphrey and a non-artist for the same task. Abstract designs were geometric figures. With these exploratory results, we now know that central questions about the production of art can be addressed.

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