How do self-attributed and implicit motives differ?

From the beginning of the work on the achievement motive (McClelland, Atkinson, Clark, & Lowell, 1953), it has been apparent that motive dispositions as coded in imaginative thought from stories written to pictures differ from motive dispositions with the same name as measured in self-reported desires or interests. The authors of the studies on achievement motivation wanted to demonstrate that the variable they had identified in fantasy functioned like an animal drive in the sense that it energized, directed, and selected behavior. In this tradition (cf. Melton, 1952) it was particularly important to show that a motivational disposition that these authors labeled n Achievement (for the need to achieve) would select behavior or facilitate learning just as hunger would facilitate a rat's learning a maze. When McClelland et al. examined a self-reported desire for achievement, they observed that it did not facilitate learning in the same way that n Achievement did and so concluded that self-reported desires do not function like motives. An early study (deCharms, Morrison, Reitman, & McClelland, 1955) showed that the two measures of achievement motivation were uncorrelated and that their behavioral correlates were different. For these reasons deCharms et al. urged that the two measures be distinguished in future research by referring to the variable identified in fantasy as n Achievement (for the need to achieve) and the self-reported desire for achievement as v Achievement (for valuing achievement).