21. Skinner believed children do bad things because the behavior obtains attention that serves as a reinforcer . 22. If the removal of an event serves as a reinforcer , this is termed negative reinforcement. 23. By matching, the subject is equalizing the price of the reinforcer they are working for. 24. Downregulation of mesolimbic dopamine receptors can result in a decrease in the sensitivity to natural reinforcers . 25. Also, a reinforcer could be delivered after an interval of time passed following a target behavior. 26. This shows that the electrical stimulation of the MFB causes a similar effect compared to natural reinforcers . 27. Similar results have been found when reinforcers are added to a context by reinforcing an alternative response. 28. There are multiple components of operant conditioning; these include reinforcement such as positive reinforcers and negative reinforcers. 29. There are multiple components of operant conditioning; these include reinforcement such as positive reinforcers and negative reinforcers . 30. Nonselective analogs are less likely to function as " reinforcers " than reuptake inhibitors that have DAT specificity.