Albert Einstein wasn't only a genius her was a very odd human being. His brain shows peculiar differences from the norm; it had many more folds than the average person. This gave the brain a greater surface area. It is like using a larger computer to do calculations.
Upon his father's death in 1955, Thomas Einstein gave the pathologist permission to preserve the brain of Albert Einstein. It was photographed then dissected into 2,000 ultra-thin slices. The slices and slides of them were later distributed to researchers.
The brain had more neurons and glia cells, well outside of the normal range; pariental lobes were unusual in the pattern of ridges and grooves. Einstein only had a brain of average size. The area controlling the tongue and face was larger, as was the region that involves attention and planning. Overall, Einstein's brain was complex. Many people think in words. He said his thinking was like a physical activity.
If selection based on "healthy" genes had been practised Einstein would never have been born. The same could be said for other great people. Sir Winston Churchill, for example, led an odd life. He would drink whisky in the evening right into the early hours and seldom got out of bed before midday.