Oxytocin: Parallel Processing in the Social Brain?

Abstract

Early studies attempting to disentangle the network complexity of the brain exploited the accessibility of sensory receptive fields to reveal circuits made up of synapses connected both in series and in parallel. More recently, extension of this organisational principle beyond the sensory systems has been made possible by the advent of modern molecular, viral and optogenetic approaches. Here, evidence supporting parallel processing of social behaviours mediated by oxytocin is reviewed. Understanding oxytocinergic signalling from this perspective has significant implications for the design of oxytocin‐based therapeutic interventions aimed at disorders such as autism, where disrupted social function is a core clinical feature. Moreover, identification of opportunities for novel technology development will require a better appreciation of the complexity of the circuit‐level organisation of the social brain.

Role of oxytocin in the control of stress and food intake

“…1,2 Hypothalamic parvocellular oxytocin-synthesising neurones project their axons to various brain regions, including the spinal cord, dorsal vagal complex, nucleus tractus solitarius, rostral ventral medulla, ventral tegmental area and hypothalamus. 1,2 Hypothalamic parvocellular oxytocin-synthesising neurones project their axons to various brain regions, including the spinal cord, dorsal vagal complex, nucleus tractus solitarius, rostral ventral medulla, ventral tegmental area and hypothalamus.…”

“…Oxytocin, a nonapeptide, is mainly synthesised in magnocellular paraventricular and supraoptic neurones of the hypothalamus, in parvocellular paraventricular neurones and, in part, in neurones of the bed nucleus of the stria terminalis in mammals. 1,2 Hypothalamic parvocellular oxytocin-synthesising neurones project their axons to various brain regions, including the spinal cord, dorsal vagal complex, nucleus tractus solitarius, rostral ventral medulla, ventral tegmental area and hypothalamus. Magnocellular oxytocin neurones, which mainly project their axon terminals to the neurohypophysis, also extend their axon collaterals to some brain regions, including the amygdala, lateral septum and nucleus of the horizontal limb of the diagonal band.…”

Regulation of stress‐induced gastric ulcers via central oxytocin and a potential mechanism through the VTA‐NAc dopamine pathway

“…Despite their identification more than 30 years ago, the functional relevance of PVN producing OT neurons is only now being fully elucidated. Recent studies have implicated these neurons in wide‐ranging physiological processes, including the regulation of food intake, gastric reflexes, respiration, and cardiovascular health . The PVN sends projections to wide‐ranging brain regions, including the VTA .…”

“…Recent studies have implicated these neurons in wide-ranging physiological processes, including the regulation of food intake, gastric reflexes, respiration, and cardiovascular health. 47 The PVN sends projections to wide-ranging brain regions, including the VTA. 2,3 We show here, in agreement with a previous study, that dopaminergic VTA neurons express OTRs.…”

A SNP, Gene, and Polygenic Risk Score Approach of Oxytocin‐Vasopressin Genes in Adolescents’ Loneliness

“…Genes in this pathway influence levels of oxytocin and arginine vasopressin in the brain. These proteins have been shown to modulate the limbic system both in mammals and humans (e.g., amygdala activation and coupling of amygdala to brainstem regions; Bale, Davis, Auger, Dorsa, & McCarthy, 2001;Domes et al, 2007;Huber, Veinante, & Stoop, 2005;Kirsch et al, 2005), explaining their influence on various social and emotional behaviors related to social inclusion (Insel, 2010), bonding and attachment (Gordon, Zagoory-Sharon, Leckman, & Feldman, 2010), and behaviors that comprise social skill deficits (Dolen, 2015). The oxytocin-vasopressin (OT-AVP) neural pathway is a promising avenue for investigation with regard to loneliness, as one should be able to bond with others to establish or maintain close relationships, and having social skill deficits would definitely impede such bonding (Eronen & Nurmi, 1999;Inderbitzen-Pisaruk, Clark, & Solano, 1992;Jones, Hobbs, & Hockenbury, 1982;Jones, Sansone, & Helm, 1983;Segrin, 1999;Segrin & Flora, 2000;Spitzberg & Hurt, 1987).…”