Psychologists recognise two types of rewards, Extrinsic and Intrinsic.
Extrinsic are your basic external status markers – salary, bonuses, promotions etc.
Intrinsic rewards are tied into increasing self-efficacy (e.g. getting better at something) and trigger the neural reward system, which in turn reinforces the activity through positive emotions.
This podcast touches on how I’m using intrinsic rewards in the early days of my course.