Operant conditioning: type of learning in which organisms associate their own actions with consequences. With classical conditioning, we learn associations between events we do not control. With operant conditioning, we learn associations between our behaviour and resulting events. B. f. skinner: modern behaviourism"s most influential and controversial figure. Likewise, behaviour followed by unfavourable consequences becomes less likely. Law of effect: concept that rewarded behaviour is likely to recur. Operant chamber (skinner box): chamber containing a bar or button that an animal can manipulate to obtain food or water (reinforcer), attached to devices that can record the animal"s rate of bar pressing or button pressing. Reinforcement: any event that strengthens the behaviour it follows, also increases the frequency of the preceding response. Shaping: procedure in which reinforcers guide behaviour toward closer and closer approximations of the desired behaviour. Positive reinforcement: increasing behaviours by presenting positive reinforcers. Negative reinforcement: increasing behaviours by stopping or reducing negative stimuli.