Individual traits shape hemispheric vlPFC sensitization to Cyberball exclusion: Evidence from single-trial fNIRS analyses

Ostracism (i.e., social exclusion) threatens social security and individuals who are hypersensitive to it may face long-term negative mental health consequences. Clarifying how self-reported distress and neural responses to ostracism unfold moment-by-moment and across varying levels of individual traits may help better understand what contributes to hypersensitivity. To this objective, the current study employed a functional near-infrared spectroscopy (fNIRS) adapted Cyberball task and single-trial analytic techniques in a sample of 53 college students (aged 18-22 years). Results confirmed that Cyberball induced ostracism increased self-reported distress and neural activity in the ventrolateral prefrontal cortex (vlPFC), a region associated with emotion regulation. Self-reported distress varied with differences in social anxiety and need for belonging. Moreover, vlPFC activity sensitized across exclusion-specific trials and this neural sensitization was differentially modulated by social anxiety, need for belonging, and personality growth mindset. The current study highlights the value of single-trial approaches for capturing the nuanced temporal dynamics of ostracism responses. Additionally, it underscores the importance of examining how individual differences shape immediate responses to ostracism to better understand their association with downstream, longer-term consequences.