The Self-Perception of intrinsic and extrinsic motivation, Journal of Personality and Social Psychology
Self-perception theory predicts that intrinsic and extrinsic motivation do not combine additively but rather interact. To test this predicted interaction, intrinsic and extrinsic motivation were both manipulated as independent variables in an experiment with 40 undergraduate males. Ss completed puzzles under payment or nonpayment conditions. Results reveal a significant interaction for task satisfaction and a trend for the interaction on a behavioral measure. Results are discussed in terms of a general approach to the self-perception of motivation.
Calder, Bobby. 1975. The Self-Perception of intrinsic and extrinsic motivation. Journal of Personality and Social Psychology. 31(4): 599-605.