We studied time-based neural activity with event-related potentials (ERPs) in young adults during a computer-simulated ball-toss game. Experiencing fair play initially, participants were ultimately excluded by other players. Dense-array ERPs showed time-dependent associations between slow-wave activity (580-900 ms) in left prefrontal/medial frontal cortical regions for exclusion events and self-reported distress. More subtle 'micro-rejections' during fair play showed a similar distress to ERP association (420-580 ms). In both cases, greater positive amplitude neural activity was associated with less post-exclusion distress. Findings suggest that rapidly occurring neural responses to social exclusion events are linked to individual differences in ostracism-related distress. Relations emerged even during fair play, providing a window into the neural basis of more subtle social-cognitive perceptual processes. © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins.