Effects of Transcutaneous Auricular Bilateral Vagus Nerve Stimulation on Social Cognition

a fundamental survival strategy.Social groups provide resources such as food, protection from external threats, and care during illness.However, being part of a social group requires specific skills, including the ability to understand and respond appropriately to others.Social cognition encompasses the abilities required to interpret and navigate our social environment, including theory of mind (ToM), empathy, joint attention, and the understanding of sarcasm.This study focuses on examining empathy and ToM as key social cognition skills.According to polyvagal theory, the development of the autonomic nervous system plays a crucial role in socialization. [1]Phylogenetic changes in the autonomic nervous system led to the development of advanced social behaviors.Notably, the myelination of the vagus nerve facilitated new social capabilities, enabling more effective interactions and Objectives: This study aims to examine the effects of transcutaneous auricular vagus nerve stimulation (taVNS) on social cognition.The research aims to investigate the effects of transcutaneous auricular vagus nerve stimulation (taVNS) on social cognition, specifically focusing on its potential to enhance social cognition abilities, strengthen the relationship between social skills, and influence the connection between Theory of Mind (ToM) and empathy.Methods: One hundred volunteers (50 female, 50 male), aged between 18 and 45 years, with no psychiatric conditions and who were suitable for vagus nerve stimulation, participated in the study.An intergroup design was employed, with participants first completing a social interest scale.The experimental group received taVNS stimulation, while the control group received sham stimulation.After a 20-minute stimulation period, participants completed the Reading the Mind in the Eyes Test (RMET) and the Questionnaire of Cognitive and Affective Empathy (QCAE).Results: The ToM results showed improvement with taVNS.However, no significant differences were observed between groups for empathy scores, except in the peripheral responsivity subdimension, where the experimental group scored lower than the control group.Conclusion: According to polyvagal theory, activation of the parasympathetic nervous system promotes a sense of safety, thereby fostering social engagement.A bidirectional relationship exists between vagal activity and social behavior.The results indicate that increased vagal activation enhanced participants' theory of mind (ToM).This sense of security frees cognitive resources, allowing individuals to focus on understanding others' mental states rather than self-protection.taVNS appears to improve theory of mind but has no significant effect on empathy or its subdimensions, except for peripheral responsivity.