Structural diverseness of neurons between brain areas and between cases

TL;DR

This study uses nanotomography to analyze neuron structures in different brain areas and individuals, revealing structural diversity linked to brain function and disease, with variations observed across cases and regions.

Contribution

It provides the first detailed nanometer-scale geometric comparison of neurons across brain areas and individuals, highlighting structural diversity and its potential functional implications.

Findings

Neuron structures differ between brain areas.

Structural dissimilarity varies between individuals.

Schizophrenia cases show geometric differences in neurons.

Abstract

The cerebral cortex is composed of multiple cortical areas that exert a wide variety of brain functions. Although human brain neurons are genetically and areally mosaic, the three-dimensional structural differences between neurons in different brain areas or between the neurons of different individuals have not been delineated. Here, we report a nanometer-scale geometric analysis of brain tissues of the superior temporal gyrus of 4 schizophrenia and 4 control cases by using synchrotron radiation nanotomography. The results of the analysis and a comparison with results for the anterior cingulate cortex indicated that 1) neuron structures are dissimilar between brain areas and that 2) the dissimilarity varies from case to case. The structural diverseness was mainly observed in terms of the neurite curvature that inversely correlates with the diameters of the neurites and spines. The analysis also revealed the geometric differences between the neurons of the schizophrenia and control cases, suggesting that neuron structure is associated with brain function. The area dependency of the neuron structure and its diverseness between individuals should represent the individuality of brain functions.