Sensitive Periods, Vasotocin-Family Peptides, and the Evolution and Development of Social Behavior.

Nicole M Baran

doi:10.3389/fendo.2017.00189

Abstract

Nonapeptides, by modulating the activity of neural circuits in specific social contexts, provide an important mechanism underlying the evolution of diverse behavioral phenotypes across vertebrate taxa. Vasotocin-family nonapeptides, in particular, have been found to be involved in behavioral plasticity and diversity in social behavior, including seasonal variation, sexual dimorphism, and species differences. Although nonapeptides have been the focus of a great deal of research over the last several decades, the vast majority of this work has focused on adults. However, behavioral diversity may also be explained by the ways in which these peptides shape neural circuits and influence social processes during development. In this review, I synthesize comparative work on vasotocin-family peptides during development and classic work on early forms of social learning in developmental psychobiology. I also summarize recent work demonstrating that early life manipulations of the nonapeptide system alter attachment, affiliation, and vocal learning in zebra finches. I thus hypothesize that vasotocin-family peptides are involved in the evolution of social behaviors through their influence on learning during sensitive periods in social development.

Highlights

Both extrinsic and intrinsic experience broadly shape the functional organization of the brain
Nonapeptide treatment altered neural activity and the expression of V1aR in the bed nucleus of the stria terminalis (BSTm) and medial amygdala (MeA) [163]. These findings suggest that AVT-injected males may have had more experience attending to social cues or a stronger association between affiliative interactions and reward compared to both Manning Compound (MC) and Control males, resulting in different approaches to reproduction
It will likely prove impossible to disentangle the direct effects of nonapeptides on the brain during development from their indirect effects resulting from how they alter the trajectory of learning from early social experiences. This conceptual challenge is at the heart of the nature “versus” nurture debate [4]. These results provide support for the idea that the actions of nonapeptides in development may play an important role in the evolution of novel social behavior

Summary

Introduction

Both extrinsic and intrinsic experience broadly shape the functional organization of the brain. The nonapeptides, which provide an evolvable mechanism for modulating the activity of whole neural circuits in specific social contexts, may play an important role in the evolution and development of social phenotypes across vertebrate taxa. The production of AVT/AVP, in from the extra-hypothalamic cell groups, is often sexually dimorphic (usually male greater than female), organized by sex steroids during development, and sensitive to changes in gonadal state [81,82,83,84,85,86,87,88].

Results

Conclusion