(Some) Intangible Rewards Increase Gameplay Time and Persistance

Reward schedules, operating on operant conditioning principles, may encourage excessive gameplay behavior. We tested fixed and variable, ratio- and interval-based reinforcement effects on gameplay duration and persistence (restarts following failure). Variable-ratio reinforcement (cf. control) doubled playtime (d = 1.26) and persistence (d = 1.19). Other effects were weaker.