Quantitative evaluation of the functional activity in multilayered brain structures using histological sections

Abstract

Subject of study. We develop an algorithm and software to estimate optical density as a correlate of neural activity in multilayered brain structures. Aim of study. We develop a method and program algorithm for quantitative evaluation of the optical density in the layers of neural structures from images of histological brain preparations that correlates with the functional activity of the cells. Method. Optical density was measured locally in successive areas of a layer or several layers of the neural structure, which are curvilinear-shaped in the brain slices. An expert researcher selects the trajectory of optical density measurement in the digitized image of the slice in an interactive mode. The results of density measurements were plotted in an orthogonal coordinate system. Capabilities enabling automated curve smoothing, extremum seeking, and calculation of distances between extrema were developed. Results. An algorithm for implementing the developed program is presented. The successive stages of operation are illustrated through the evaluation of the optical density in the visual cortex layer from an image of a brain slice as an example. In addition, the evaluation results of the optical density in layers of a lateral geniculate body are presented. Practical significance. The developed method and program algorithm are required for reconstructing the functional activity of the curved layers of different brain structures to investigate and simulate the organization patterns of the neural networks of the human brain.