Sorting Out a 150-Year-Old Brain-in-Jar Mix-Up

via Gaetan Lee/Flickr

We’ve all been there: You’ve got a bunch of human brains in jars, and you’re taking them out and looking at them and measuring them and working hard and whoops!—Which brain goes in which jar?

It’s a dilemma as old as the practice of putting brains in jars, and it’s troubling because how are you ever going to sort out whose brain is whose? Renate Schweizer, a neuroscientist at the Max Planck Institute for Biophysical Chemistry in Göttingen, Germany, just sorted out a 150-year-old brain-in-jar mix-up, and has once again properly labeled the brain of the famous mathematician Carl Freidrich Gauss.

Johann Carl Friedrich Gauss died in 1855 in Göttingen, leaving behind a legacy as one of the all-time greatest mathematicians for his contributions to number theory, geometry, probability theory, geodesy, planetary astronomy, the theory of functions, and potential theory. There’s not only “Gauss’s Law” which pertains to electric fields, but also Gauss’s law for magnetism and for gravity. He’s such a heavyweight that Wikipedia has a whole page just devoted to things named after him.

In addition to this legacy, when he died, Gauss left behind his beautiful brain. The anatomist Rudolf Wagner—who was both friends with Gauss and on the leading edge of the anthropological measuring people craze—examined and stored Gauss’s famous brain, reporting that, at 1,492 grams, it was slightly larger than average, but otherwise pretty anatomically normal.

The same year, 1855, the medical scholar and founder of the University of Göttingen’s anatomical pathology collection, Conrad Heinrich Fuchs, died. Wagner gave Fuchs’s brain the same treatment, preparing brain slices and publishing his findings and drawings of Fuchs’s brain in between 1860 and 1862.

Flash forward to the present. Renate Schweizer was researching the part of brain around the “central fissure.” She suspected that Gauss had a rare, visible division in the central fissure of his brain, and found it in MRI scans taken in 1998, of the brain labeled as Gauss’s. A divided central fissure is very rare, found in less than one-percent of the population.

However, when she looked back at Wagner’s drawings of Gauss’s brain, Schweizer didn’t find the divided central fissure. Instead the MRI images were a perfect match for Wagner’s drawings of Fuchs’s brain.

Wagner’s drawings of Fuchs’s brain on the left, and Gauss’s brain on the right, with an MRI of Gauss’s brain in the middle, via Jens Frahm and Sabine Hofer / Biomedizinische NMR Forschungs GmbH 2013

She went to the Institute of Ethics and History of Medicine, and discovered the brain that Wagner attributed to Fuchs was in the jar labeled Gauss, and vice versa. “My theory, according to the information currently available, is that the brains were probably put into the wrong jars relatively soon after Wagner’s examinations, at the time when the surface of the cerebral cortex was being measured again,” Schweizer said in the university press release.

At any rate, the brains are now in their properly labeled jars. Both brains of both men are fairly normal, much to the disappointment of phrenology-fans everywhere, no doubt, although Gauss’s did show signs of high-blood pressure.