BRAIN A JOURNAL OF NEUROLOGY LETTER TO THE EDITOR A rare anatomical variation newly identifies the brains of C.F. Gauss and C.H. Fuchs in a collection at the University of Go ¨ ttingen Renate Schweizer, 1 Axel Wittmann 2 and Jens Frahm 1 1 Biomedizinische NMR Forschung GmbH am Max-Planck-Institut fu ¨ r biophysikalische Chemie, Go ¨ ttingen, Germany 2 Institut fu ¨ r Astrophysik, Universita ¨t Go ¨ ttingen, Germany (retired) Correspondence to: Renate Schweizer, Biomedizinische NMR Forschungs GmbH am Max-Planck-Institut fu ¨ r biophysikalische Chemie, Go ¨ ttingen, Germany, Am Fassberg 11, 37070 Go ¨ ttingen, Germany E-mail: rschwei@gwdg.de Sir, Recently, Falk et al. (2013) analysed original photographs of the brain of Albert Einstein in an article published in Brain. The authors state that ‘... we also hope that our identifications will be useful for workers inter- ested in comparing Einstein’s brain with preserved brains from other gifted individuals, such as the German mathematician Carl Friedrich Gauss (1777–1855) ...’. Since 1855 the brain of Carl Friedrich Gauss has been kept as part of a small collection of preserved (elite) brains at the University of Go ¨ ttingen, currently (since 1995) in the Institute of Ethics and History of Medicine. Shortly after Gauss’s death in 1855, his brain was dissected—with authorization and under the restriction to be only used for scientific studies—by a group of experts led by Rudolf Wagner, a friend of Gauss and physiologist at the University of Go ¨ ttingen. Wagner published two scientific studies, in which he described a variety of brains using different metrics, such as total brain weight or volume (Wagner, 1860, 1862). In the 1860 work he specifically focused on the convolutions of the cortex of ‘intelligent men’ considering this a novel and promising approach to assess differences between individual brains, rather than the somewhat crude measures of brain weight and volume. The descriptions of both studies are complemented by a set of copper engravings (Wagner, 1860) and lithographs (Wagner, 1862) made by H. Loedel, depicting the studied brains with great precision and naturalistic accuracy. In 1998, in parallel with a necessary renewal of the fixative used to preserve the brain in a glass jar labelled ‘C.F. G__ss’, structural MRI was conducted by our group for documentary reasons. A detailed account of the procedures as well as an MRI reconstruc- tion of the cortical surface was reported (Haenicke et al., 1999; Wittmann et al., 1999). In a letter to Science, Frewer and Hanefeld (2000) referred to these MRI results in relation to find- ings from the brain of Albert Einstein, stating that the Gauss brain does not share the lack of the parietal operculum. Recent high-resolution functional MRI studies of the primary somatosensory cortex in our laboratory (Schweizer et al., 2008) have brought the rare condition of a divided central sulcus to our attention (Alkadhi and Kollias, 2004). It is caused by an elevated pli de passage fronto-parietal moyen (Broca, 1888), which nor- mally represents a deep convolution in the fundus of the central sulcus connecting the pre- and postcentral gyrus. In some rare cases this deep convolution extends to the surface of the brain, presenting itself as a connective structure between the two gyri. This infrequent anatomical variation of a divided central sulcus can clearly be seen in the MRI surface reconstruction of the left hemi- sphere of the brain in our earlier publications (Haenicke et al., 1999; Wittmann et al., 1999). The historical first description of ‘bridges connecting the two cen- tral convolutions’ was indeed made by Rudolph Wagner (1862). Although these bridges are virtually identical to the divided central sulcus seen in our MRI surface reconstructions of the believed-to-be Gauss brain, Wagner’s description was unambiguously assigned to the brain of the famous physician Conrad Heinrich Fuchs (1803– 1855), who died in the same year as Gauss (Wagner, 1862). Subsequent inquiries at the University of Go ¨ ttingen revealed a glass jar labelled ‘C.H. F__s’ similar to the glass jar in which the doi:10.1093/brain/awt296 Brain 2014: 137; 1–2 | e269 Advance Access publication October 26, 2013 ß The Author (2013). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com