Conference Agenda

Oxytocin (OXT) is an allostatic hormone and has been hypothesized to modulate sensitivity to social information that confirms or contradicts a child’s existing expectations about the availability of parental support. Research suggests that OXT levels in anticipation of stress moderate the association between parenting and changes in attachment, such that higher OXT levels are linked to a stronger association between these constructs. In the current study, we analyzed whether OXT measured in anticipation of a stressful task modulates the extent to which attachment is linked to children’s subjective and physiological stress responses to praise and critical comments which they believed came from their parents. The experiment consisted of a block of praise comments followed by a block of critical comments. Before and after each block, we assessed children’s subjective emotional states, and during the task we measured their physiological stress responses. Subjective responses were measured using a Visual Analogue Scale (VAS), while physiological responses were measured via heart rate variability (HRV). We collected salivary OXT from 100 children before the start of the praise/criticism task. In addition, children’s level of secure attachment was measured with the Middle Childhood Attachment Script Assessment (MCASA). We hypothesized that the association between attachment and changes in subjective and physiological stress responses to praise or criticism would be stronger in children with high baseline OXT. We expected a high level of secure attachment to be linked with stronger reactions to praise, and a lower level of secure attachment to be linked with stronger reactions to criticism. Data have been collected, and analyses are planned.

Epistemic trust, or trust in communicated knowledge, enables humans to use social information to guide decision-making. The level of trust humans place in information depends on informant identity, as people are more likely to trust smart or in-group informants. Although the neurohormone oxytocin has been extensively studied in affiliative behavior, its influence on epistemic trust has received less attention. Rodent models may help advance this research, as social transmission of food preference (STFP) may be functionally related to elements of human epistemic trust. During STFP, rodents learn about food safety by interacting with a conspecific, and, similar to humans, adjust their ‘trust’ in social information based on cues such as informant familiarity. We combined effect sizes from five human studies (N = 414) and three rodent studies (N = 330), revealing no significant overall effect of oxytocin administration on epistemic trust in humans (g = 0.25, 95 % CI: –0.25 to 0.75, p = .23) or STFP acquisition in rodents (g = –0.02, 95 % CI: –0.60 to 0.56, p = .84), with substantial heterogeneity across samples. Narrative syntheses suggest that oxytocin can enhance or reduce trust in social information depending on who provides it and who receives it. These findings support the allostatic model, which proposes that oxytocin modulates information processing and learning to help organisms remain optimally adapted to their environment. For instance, in humans, oxytocin decreased trust in advice when participants already performed well on a task, but increased it when they performed poorly, suggesting that oxytocin adaptively adjusts thresholds to trust information. This study advances epistemic trust as a framework to test predictions of the allostatic model of oxytocin, and validates the STFP paradigm as translational tool to probe underlying neural mechanisms. Given that oxytocin has been considered a standalone or adjunctive psychiatric treatment, clearer insights into its effects may explain inconsistent clinical outcomes.

Social interactions are an inherent cornerstone of human behavior. One neurobiological system suggested to underlie and facilitate pro-social functioning is the oxytocinergic system. In the human brain, oxytocin is synthesized in the hypothalamus, where it acts as a key neuromodulator mediating a broad range of affiliative behaviors, including interpersonal bonding, social attunement, and attachment. These effects are thought to arise, at least in part, from oxytocin’s role in modulating social salience and regulating central and autonomic nervous system function, thereby shaping (social) stress and anxiety responses. In light of these purported functions, the oxytocinergic system has emerged as a compelling therapeutic target for neurodevelopmental conditions characterized by difficulties in social functioning and stress regulation, most notably autism spectrum disorder. This talk will provide an overview of oxytocin research in autism, with a particular focus on recent mechanistic and clinical studies investigating the effects of (chronic) intranasal oxytocin administration in human trials. Integrated treatment–mechanistic insights from pharmaco-neuroimaging, (epi-)genetic approaches, and measurements of endogenous oxytocin levels will be discussed. In addition, emerging microbiological research on oxytocin’s role in gut dysbiosis and its bidirectional interactions with microbiome composition will be reviewed. Finally, directions for advancing oxytocin-based therapeutic approaches will be outlined, emphasizing the importance of attaining a detailed understanding of the absorption pathways and neural mechanisms that shape oxytocin’s behavioral outcomes. To this end, a conceptual framework will be presented that integrates current insights into the modulatory influence of contextual factors on endogenous oxytocinergic signaling, and delineates how endogenous release dynamics may interact with exogenously administered oxytocin across distinct spatial and temporal scales. This integrative perspective aims to account for interindividual variability in treatment response and to guide more precise, mechanism-informed clinical applications of oxytocin in autism.

Discussant