What happens when a person is offered an incentive to do something the individual would have done anyway, without incentive? Back in 1975 Edward Deci, Mark Lepper, and their colleagues proposed that rewards undermine intrinsic motivation. In contrast, Len Sushinsky and I argued that the effects of rewards depend on how you use them. If you reward a person for just spending time in an activity, the person will become bored with the activity. If you reward a person for learning a new skill, however, the person is likely to show greater interest in the activity. We also asserted the significance of the symbolic effects of the reward. When reward symbolizes success, for example, intrinsic interest should be enhanced. Back in 1975 we were especially critical of the social psychology experiments that used single trial rewards because novel rewards can be distracting.
That was 35 years ago. In the interim many studies were conducted on intrinsic and extrinsic motivation. To prove that rewards undermine intrinsic interest, researchers needed to demonstrate each of the following: construct validity; reliable measures; experimental controls; and favorable experimental results. Let's see what happened.
I believe that intrinsic - extrinsic motivation is an invalid distinction. I would argue that intrinsic-extrinsic motivation is a modern version of mind-body dualism, such that intrinsic motives (e.g., curiosity, self-determination) are those of the mind, while extrinsic motives (e.g., hunger, sex) are those of the body. In any event, I do not think that motives can be divided into just two types. On the contrary, I think there are 16 intrinsic motives (or "needs") and no extrinsic motives. I have no idea how to even state undermining theory when it is appreciated that any of 16 intrinsic needs can motivate interest in an activity, and any of 16 needs can motivate interest in a reward.
I question the reliability of behavioral measures of intrinsic interest. What activities a child chooses while running around a nursery school may vary from day to day for no particular reason. In any event, I do not recall a study demonstrating the test-retest reliability of the behavioral measure of intrinsic motivation. I believe that measures of self-reported interest are reliable, so if I were to review the literature, I would focus only on the results with self report measures.
Further, I think certain interpretations of the behavior measure have led to circularity and self-fulfilling prophecy. Suppose we offer a boy a prize for making a good drawing; the boy draws and gets the prize; and now we observe the boy to see if he still draws on his own. If the boy draws little after having earned the prize, undermining theorists would interpret this as evidence of decreased intrinsic motivation. However, if the boy draws often after having earned the prize, undermining theorists would not interpret this as evidence of increased intrinsic motivation. That is, the boy drawing less supports undermining theory, but the boy drawing more doesn't contradict it. When the boy draws more, undermining theorists assume that the child was looking for a reward and, thus, was extrinsically motivated. When the boy draws less, undermining theorists assume that the child could not have been looking for an incentive and, thus, was intrinsically motivated. This "heads I win, tails you lose" thinking is circular; it biased the publication process by mis-identifying disconfirming studies as invalid. Many studies that did not support undermining theory were never published because of this faulty logic applied in the peer review process.
The undermining studies did not control for the known negative effects of reward. Especially when rewards are novel -- nearly all of the undermining studies used only one trial of reward -- they can be distracting, arouse performance anxiety, or even cause doubt that the experimenter will actually give the reward as promised.
Even after setting aside the above issues, meta-reviewers hoping to demonstrate undermining theory still needed to exclude some unfavorable studies to do so. The mentality of "let's include this study in the meta-review, but not that study" went to what I would regard as extremes. Studies that contradicted undermining theory -- such as a study I published in the Journal of Personality and Social Psychology in 1975 -- were not counted in meta-reviews, while the 1977 study by Smith and Pittman was included as supporting undermining even though this study gave multiple trials of a reward that symbolized failure.
Personally, I object to intrinsic-extrinsic motivation because it offers "one size fits all" solutions for educating children and motivating adults. I believe, for example, that some children thrive with cooperative learning, others thrive with competitive learning situations, but intrinsic-extrinsic motivation theory wants all children to grow up with cooperative learning. In the name of self-determination, undermining theory imposes its values on others believing it is for their own good. I think undermining theory could be misused to teach children who are competitive by nature that something is wrong with them for enjoying competition.
Intrinsic-extrinsic motivation has become a dead end. I have seen teachers mope around saying they can't do anything to help students because "the intrinsic motivation has been beaten out of them." Our schools do not need a theory that can function as an excuse for inaction.
Although I disagree with undermining theory, I commend the related social psychological discussion on self-determination. I think the discussion has served to promote policies that helped people with disabilities. I think intrinsic motivation is at its best when used to promote freedom, including the freedom to pursue material rewards. I think undermining theory is at its worst when it implies support for freedom except when people choose materialism, capitalism, or values different from those of undermining theorists.
