Functional craniology and brain evolution: from paleontology to biomedicine

Abstract

Anatomical systems are organized through a network of structural and functional relationships among their elements. This network of relationships is the result of evolution, it represents the actual target of selection, and it generates the set of rules orienting and constraining the morphogenetic processes. Understanding the relationship among cranial and cerebral components is necessary to investigate the factors that have influenced and characterized our neuroanatomy, and possible drawbacks associated with the evolution of large brains. The study of the spatial relationships between skull and brain in the human genus has direct relevance in cranial surgery. Geometrical modeling can provide functional perspectives in evolution and brain physiology, like in simulations to investigate metabolic heat production and dissipation in the endocranial form. Analysis of the evolutionary constraints between facial and neural blocks can provide new information on visual impairment. The study of brain form variation in fossil humans can supply a different perspective for interpreting the processes behind neurodegeneration and Alzheimer’s disease. Following these examples, it is apparent that paleontology and biomedicine can exchange relevant information and contribute at the same time to the development of robust evolutionary hypotheses on brain evolution, while offering more comprehensive biological perspectives with regard to the interpretation of pathological processes.

Human Paleoneurology and the Evolution of the Parietal Cortex

“…In terms of spatial correspondence, the morphological changes associated with the precuneus at intra-and interspecific levels match the parietal bulging described in the endocranial evolution of modern humans [Bruner et al, 2014a].…”

“…Neanderthals and modern humans share a similar cranial capacity, but the latter shows a general enlargement of the parietal lobes (f -digital replica of skull and endocasts of the Neandertal Saccopastore 1, and shape deformation associated with modern human endocranial anatomy). Images after Bruner [2004Bruner [ , 2010Bruner [ , 2014 and Bruner et al [2004Bruner et al [ , 2014aBruner et al [ , 2015c.…”

“…If we consider only the parietal landmarks (below), PC1 (67%) separates again humans from apes because of the enlargement of the dorsal and anterior regions of the parietal lobe. In this example, endocasts from 1 representative individual of each species (adult males) were used, averaging 10 replicas and the 2 hemispheres, so as to limit uncertainty due to landmark localization (data after Pereira-Pedro and Bruner [2018] cranial heat exchange, and the bulging of the parietal region characteristic of modern humans can hence contribute to increase the heat load of the corresponding deeper cerebral areas [Bruner et al, 2012[Bruner et al, , 2014a. Ontogenetic analysis of the endocranial form suggested that modern human brain globularity is achieved early postnatally [Neubauer et al, 2009] et al, 2016].…”

Cortical surface area and cortical thickness in the precuneus of adult humans

“…Published by Elsevier Ltd. All rights reserved. modern human brain morphology may be associated with form changes in these medial parietal element (Bruner et al, 2014b).…”

Correlations Between Dental Malocclusions, Ocular Motility, and Convergence Disorders: A Crosssectional Study in Growing Subjects

“…This network of relationships generates the set of rules orienting and constraining the morphogenetic processes (1). Continuous afferent impulses from the eyes, labyrinths, muscles, and joints inform the individual about the position of the body (2).…”