A unique case of naturally occurring mummification of human brain tissue

Abstract

When skulls and bones were exhumed from a mass grave in Bulgaria and subjected to medicolegal examination they were found to originate from 39 humans aged 36-60 years old who had been buried approximately 45-50 years ago. Solid structures which strongly resembled shrunken human brain tissue were found inside 2 intact skulls. Among other bones 5 similar structures were found one of which was an almost entirely preserved human brain, and the others were fragments from different regions of the human brain. Samples of these structures were immersed in 15% aqueous glycerol solution to soften and were examined by light and electron microscopy. Samples of this material and of fresh human brain were subjected to elementary atomic spectral analysis. These complex studies indicated the samples to be naturally mummified human brain tissue and that this process had occurred due to specific conditions within the cranial cavities after burial.

Human mummified brain from a medieval tomb with lime‐soil mixture barrier of the Joseon Dynasty, Korea

“…Similar findings were also reported in work on the brains of Inca mummies (Previgliano et al, 2003) where both the white matter and the grey matter were clearly discernible. In a cross-sectioned examination on a mummified brain by Radanov et al (1992), they also reported 'a distinguishable, non-uniformly outlined, thin outer band, greyishblack in color, suggestive of the cortex; and below a zone of whitish-grey color resembling the white substance of the brain'. Since we also found compartmentalised regions of grey and white matter in the cross-sections of the mummified brain that we studied, it can be said that the current case shares a common morphological pattern with those of previously reported cases of mummified brains.…”

“…However, a contradictory view on the preservation of mummified brains has also been suggested. As an answer to the question of why brains have been preserved as mummified tissue even after all other tissues have disappeared, leaving only skeletal remains (Radanov et al, 1992), Hess et al (1998) speculated that myelin sheaths and collagen fibres show remarkable resistance to tissue disintegration. According to Figure 4.…”

“…Such examples include 8000-year-old human brain tissue from the Windover archaeological site (Doran et al, 1986); a 7000-year-old human brain excavated from Little Salt Spring in southwestern Florida (Pääbo et al, 1988); brains of Inca mummies (Previgliano et al, 2003); naturally mummified Chilean brains from 1000 BC to 1500 AD (Gerszten & Martinez, 1995); mummified brains from burials approximately 45-50 years ago (Radanov et al, 1992); a naturally mummified brain from the Bushveld, South Africa (Eklektos et al, 2006); brains from the Augustinian Friary at the Magistrates' Court of Hull (O'Connor, 1999); a case of an ancient Egyptian brain tumour (Ask-Upmark, 1960); meningioma in an age-old brain (Campillo, 1991); brains preserved in medieval skulls (Tkocz et al, 1979); and the famous Tyrolean Ice Man (Hess et al, 1998). However, a contradictory view on the preservation of mummified brains has also been suggested.…”

Mummies

“…This may result in an excellent morphological preservation showing gyri and sulci and main brain parts (hemispheres, hindbrain, medulla oblongata with the pons, etc.) (Padanov et al, 1992). The brain may in other circumstances liquefy postmortem, so that only a hardened ''rim'' along the inside of the skull remains.…”

“…Adipocerous change is not uncommonly found in the brain, since brain tissue is also high in fat content. Thus well-preserved brains may be found even if all other soft tissue has decomposed (Tkocz et al, 1979;Radanov et al, 1992). Adipocire was previously thought to be a process of saponification of organic fatty acids in the presence of lime or calcium carbonate (Micozzi, 1991).…”