Morphometric Methods in Sexual Dimorphism Research on the Central Nervous System

This chapter describes the analysis of thickness of cortical structures, the volume of different brain regions, and the cell and synapse counting within a given brain area and discusses the several currently employed morphometric methods.

Abstract

This chapter describes the analysis of thickness of cortical structures, the volume of different brain regions, and the cell and synapse counting within a given brain area. It also discusses the several currently employed morphometric methods. The analysis of thickness of a given brain region is important to deal with a large structure, such as the cerebral cortex, where an initial screening for detecting differences between two or more groups is desirable before proceeding to a more detailed analysis. When a cortical thickness analysis is performed involving groups with a chance that not all cortical areas will be equally affected, identical cortical regions must be compared. Relative (shrinkage-insensitive) parameters appeared to be profitable in demonstrating a sex dimorphism in the lateralization of the orbital prefrontal cortex both during development and in adulthood. For counting synapses and neurons, the numerical density per unit section area is noninformative. A better parameter is either the numerical density per unit volume or the total number in a particular brain region.