An extinction burst is a temporary increase in the rate of an operant response that follows the withdrawal of the reinforcement maintaining it [1][2]. It is a transitional phenomenon, confined to the period immediately after the transition to extinction rather than persisting as a new steady state [2]. Whether it is detected depends on measurement: prevalence is considerably higher when only the first minute after the transition is scored than when response rates are averaged across the session [3]. Bursts are not universal; in applied treatment of problem behaviour, bursting and extinction-induced aggression occur in nearly half of cases and are less frequent when extinction forms part of a treatment package than when used alone [4].