But a new analysis of Einstein's brain by Canadian scientists, reported in the current Lancet, reveals that it has some distinctive physical characteristics after all. A portion of the brain that governs mathematical ability and spatial reasoning--two key ingredients to the sort of thinking Einstein did best--was significantly larger than average and may also have had more interconnections among its cells, which could have allowed them to work together more effectively. While the case is far from proven, says Dr. Francine Benes, director of the Structural Neuroscience Laboratory at McLean Hospital in Belmont, Mass., "it's a fascinating discovery."
The curious tale of how the brain got to McMaster University, in Hamilton, Ont., is equally fascinating. When Einstein died of a ruptured abdominal aneurysm in 1955, at the age of 76, the pathologist who did the autopsy at Princeton Hospital, Dr. Thomas Harvey, removed the brain, pickled it in formaldehyde--and kept it. Harvey had no credentials in neuroscience, and his unauthorized appropriation of Einstein's brain appalled and outraged many scientists. Possession was evidently a point in his favor, though. At the pathologist's request, the family agreed he could keep the organ for scientific study. But over the next four decades Harvey, who now lives in Lawrence, Kans., doled out little in the way of either published findings or bits of brain for others to examine. For a while, according to several reports, he stored the thing behind a cooler in his office.
Finally, in 1996, Harvey gave much of his data and a significant fraction of the tissue itself to Dr. Sandra Witelson, a neuroscientist who maintains a "brain bank" at McMaster for comparative studies of brain structure and function. These normal, undiseased brains, willed to science by people whose intelligence had been carefully measured before death, gave Witelson a solid set of benchmarks against which to measure the seat of Einstein's brilliant thoughts. To make the comparison as valid as possible, Witelson and her team compared Einstein's tissues with those of men close to his age.
What they found was that while the overall size of Einstein's brain was about average, a region called the inferior parietal lobe was about 15% wider than normal. "Visuospatial cognition, mathematical thought and imagery of movement," write Witelson and her co-authors, "are strongly dependent on this region." And as it happens, Einstein's impressive insights tended to come from visual images he conjured up intuitively, then translated into the language of mathematics (the theory of special relativity, for example, was triggered by his musings on what it would be like to ride through space on a beam of light).
Not only was Einstein's inferior parietal region unusually bulky, the scientists found, but a feature called the Sylvian fissure was much smaller than average. Without this groove that normally slices through the tissue, the brain cells were packed close together, permitting more interconnections--which in principle can permit more cross-referencing of information and ideas, leading to great leaps of insight.
That's the idea, anyway. But while it's quite plausible according to current neurological theory, that doesn't necessarily make it true. We know Einstein was a genius, and we now know that his brain was physically different from the average. But none of this proves a cause-and-effect relationship. "What you really need," says McLean's Benes, "is to look at the brains of a number of mathematical geniuses to see if the same abnormalities are present."
Even if they are, it's possible that the bulked-up brains are a result of strenuous mental exercise, not an inherent feature that makes genius possible. Bottom line: we still don't know whether Einstein was born with an extraordinary mind or whether he earned it, one brilliant idea at a time.