Motivation to engage a task can have both an intrinsic and an extrinsic component (Lepper, Corpus & Iyengar, 2005). The intrinsic component stimulates task engagement out of a desire for challenge, pleasure and interest (Lepper et al, 2005). This is called intrinsic motivation.
The extrinsic component stimulates task engagement out of a desire for external reward or dodging punishment. This is called extrinsic motivation. If there's no internal or external stimulus to engage a task it's called amotivation (Deci & Ryan, 1985).
These motivation components are non-homeostatic drive-forces to engage a task (Gorman, 2004, White, 1959), motivation that holds no relation to direct physical needs like hunger and thirst. The concepts of intrinsic and extrinsic motivation have originated from the comments of White (1959) on the drive theories of motivation (Deci & Ryan, 1985; Harter, 1978; White, 1959). The drive theories of motivation ascribe task motivation and desire to learn to a desire for external rewards or dodging of punishment. White (1959) used a variety of sources to show that external stimuli alone, are inadequate to explain the full range of human behaver like discovery, play, and a desire to deal with one's surroundings competently.
White (1959) proposed that many behaviors are explained better from a desire to deal with one's surroundings competent and effectively. Harter (1978, 1981), Deci and Ryan (1985) and others after him have operationalised the concepts White (1959) proposed too subsequently test it. His critique has since been tested and supported with evidence. A large part of this research has been done in the context of children and their development in education, some even longitudinal.
Both intrinsic and extrinsic motivation have their place during the development of children. Though time after time research has shown a correlation between school results and intrinsic motivation for school (Lepper et. al, 2005). Partly because of this, intrinsic motivation is seen as superior to extrinsic motivation. However if a child is amotivated to engage in a certain task at school, rewards may be applied to increase task motivation through extrinsic motivation (Deci & Ryan, 1985, pp. 263-264).
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