Cyberball Social Exclusion

Cyberball is a widely-used paradigm for experimentally inducing social exclusion. Participants play an online ball-tossing game with two computer-controlled players. In the exclusion condition (default), participants receive the ball only twice during the first few exchanges and are then completely ignored for the rest of the game. In the inclusion condition, participants receive every third throw throughout. Whenever participants hold the ball, it goes to the player they choose.

After the game, participants complete the 20-item Need Threat Scale (Williams, 2009), measuring how much the experience threatened four fundamental social needs: belonging, self-esteem, meaningful existence, and control. All items are rated 1 (Not at all) to 5 (Extremely). As in Williams (2009), the scale is scored as need satisfaction: the nine negatively worded items are reverse-scored, so higher scores mean a need was more satisfied, and exclusion lowers them.

The paradigm follows the original computerised Cyberball design described in Williams, Cheung & Choi (2000), which showed that even ostracism by strangers over the internet reliably threatens all four needs. Zadro, Williams & Richardson (2004) extended this to show that ostracism by an obviously computer-controlled player produces equivalent need threat — supporting the robustness of the effect and the suitability of this fully automated version.

Condition assignment. Use Open Lab's condition-assignment feature to randomly assign participants to _condition = "exclusion" or _condition = "inclusion". The default is exclusion.