Unlike cognitive load, ego depletion is at least in part a loss of motivation. After exerting self-control in one task, you do not feel like making an effort in another, although you could do it if you really had to. In several experiments, people were able to resist the efforts of ego depletion when given a strong incentive to. In contrast, increasing effort is not an option when you must keep 6 digits in short-term memory while performing a task. Ego depletion is not the same mental state as cognitive busyness.