DRL schedules have been used in rodents to measure the ability to wait to make an action (as opposed to the ability to wait for reinforcement following a choice, as in delay discounting – see below); in these procedures, appetitive reinforcement occurs only if a response is made after a certain, relatively long interval of time has passed.61 Waiting impulsivity is assessed by how frequently early responses are made, and by consequence, how many rewards are forfeited.
