Friday, November 16, 2012

Albert Einstein's extraordinary brain

The most striking feature of Albert Einstein's brain is that the sylvian fissure ends abruptly as it progresses posteriorly, running straight into the postcentral sulcus. This means he didn't have a parietal operculum: the brain region responsible for higher-order somatosensory processing. As a result, his inferior parietal lobule, responsible for abstract spatial reasoning, was proportionally enlarged.

To see this for yourself, look at figure 1c below. The sylvian fissure is the horizontal groove running from the front (right) of the brain towards the back. Notice how, about a third of the way back, it turns up sharply. The resulting vertical groove is the postcentral sulcus, often an entirely separate structure.


Compare that to a more typical brain, where the sylvian fissure is much longer (but, in this case, still contiguous with the postcentral sulcus:



I don't see why this would matter, or if it even stands up to familywise error correction, but Einstein also had a low neuron:glia ratio in his left angular gyrus, part of the temporoparietal junction, an area involved in understanding other people's mental states.