figure 8.18 Einstein’s brain After his death, the brain of the great physicist Albert Einstein was removed and analyzed to see whether there were any biological clues to his exceptional genius. Researchers found that Einstein lacked one of the grooves (the Sylvian fissure) that is normally found in the human brain (Witelson, Kigar, & Harvey, 1999). The researchers speculated that the absence of this groove may have enabled Einstein to develop an exceptionally dense network of interconnections among brain cells. This unique network of interconnections may have fueled his unique mental power.