Salivary Oxytocin Research Clings Strongly to Early Theories, Despite New Frameworks Attributing Versatile Roles to the Neuropeptide

Salivary oxytocin is a widely used peripheral measure for investigating neuroendocrine correlates of social, stress-related, and adaptive physiological processes. While theoretical interpretations of oxytocin have evolved substantially beyond early prosocial accounts and recognized context dependency, individual variability, and regulatory functions, more recent studies introducing oxytocin measures in non-human species often rely exclusively on early prosocial interpretations. This striking limitation to just one of several conceptualizations prompted us to examine how theoretical perspectives are represented in the literature on salivary oxytocin. To address this, we conducted a bibliometric and semantic analysis of 445 publications on salivary oxytocin (2005-2026) to identify historical trends, citation patterns, thematic concentrations, and alignment with current theoretical frameworks. A citation analyses revealed the dominance of early canonical studies, with a small number of papers accounting for a disproportionate share of citations. Keyword and semantic cluster analyses identified seven thematic domains, including stress research, parental care, and clinical studies, while integration across species was limited. Explicit citation of selected landmark publications representing major conceptual frameworks of oxytocin function was uncommon (16.6% of studies), with human studies primarily referencing the publication representing social salience theory and animal studies primarily referencing the publication representing the prosocial framework. Thus, despite its evolutionary conservation and translational potential, salivary oxytocin research showed limited explicit theoretical engagement, while citation and semantic patterns remained disproportionately centered on early socially oriented literature. Together, these findings suggest that the rapid expansion of the field has not been accompanied by comparable structural diversification. This highlights the need for future research to apply models, integrate findings, and contextualize applications to produce informed insights into oxytocin’s physiological, behavioral, and adaptive functions.