Let’s increase the complexity of the problem. Instead of colours, you now have numbered thoughts. Just like before, these have to be sorted into bins with a corresponding number. To make this trickier the numbers on the buckets are hidden unless you hover over to check, and this is expensive in terms of energy. So it pays to learn the position of the numbered bins quickly, so you can sort the thoughts into the right destination. This represents the cost of learning something new, and the relatively lower cost of being able to recall it reliably.

Like before there is a limited energy that burns more quickly while handle each thought, and while you hover to check the number of a bucket.