Less than eight hours after his death, Einstein's brain was removed by Thomas Harvey, a Princeton pathologist. Decades later, UC Berkeley scientist Marian Diamond examined samples of Einstein's brain tissue.
While his brain didn't have a lot of extra neurons, Diamond found that it did have an abnormally higher concentration of glial cells (astrocytes and oligodendrocytes) in areas controlling imagery and complex thinking.
What's more, his corpus callosum, (which allows the hemispheres of the brain to communicate with one another) had much thicker connections between the halves of his prefrontal cortex (abstract thinking and decision making), parietal lobe (sense and motor function) and visual cortex.
Scientists believe these stronger connections were partially responsible for his amazing intelligence.