Evolutionary Formation and Functional Significance of the Core–Belt Pattern of Neural Organization of Rostral Auditory Centers in Vertebrates

Abstract

We survey the literature data on rostral auditory centers in amniotes with a focus on their core–belt neural organization, as related to lemniscal (core) and extralemniscal or non-lemniscal (belt) pathways. Our immunohistochemical results on the distribution of the calcium-binding proteins, parvalbumin (PV) and calbindin (CB), in the pigeon mesencephalic (MLD) and thalamic (Ov) auditory centers clearly demonstrate the presence of this cytoarchitectonic pattern of neural organization in birds. We analyze its functional significance for the optimal integration of the results of perceptual auditory information processing and its affective assessment due to neural connections between the belt regions of auditory centers and limbic centers. In the latter, specifically in the amygdala, there are audiomotor and audiovegetative relays responsible for the choice and implementation of behavioral types most adequate to each given context. A comparative analysis of different characteristics of auditory centers across a broad range of vertebrates allows hypothesizing about the origin, conservation and transformation of the core and belt regions of auditory centers during evolution.