Cognitive Load Theory (hereafter CLT) is a cognitive psychology theory about the mental effort placed on working memory during learning. CLT divides cognitive load into three kinds: intrinsic load, extraneous load, and germane load. The key point is that working memory, which is where this load lands, is extremely limited.
I also apply CLT beyond learning, to knowledge work in general. Because human working memory is so limited, it is best to minimize the load of the work itself in knowledge work.
In algorithmic terms, it is like solving an algorithm problem on a computer with very little RAM. So you should design your workflow to reduce space complexity rather than time complexity.
Types of Cognitive Load
CLT divides cognitive load into the following three types. Here I use writing as the example.
Intrinsic load
This is the load built into the cognitive task itself, and it cannot be reduced.
In the writing example, it looks like this:
- Coming up with ideas
- The complexity that comes from the topic itself
- Composing sentences
I said it cannot be reduced, but over the long term it can be. If the topic is familiar, intrinsic load decreases. Still, it is hard to reduce intrinsic load immediately. Think of intrinsic load as a hard core that you can neither increase nor decrease.
Extraneous load (Extraneous load)
This is load unrelated to the cognitive task itself. It can go up or down, and the lower it is, the better. For example, you can think of all UX as aiming to reduce this extraneous load.
In the writing example, it looks like this:
- The fatigue of editing because my handwriting is bad
- Phone notifications that arrive while I'm writing
- The load of keeping the overall flow in my head instead of writing it down somewhere
Germane load
This is the load spent on building schemas and automating them. If you take on this load, you get better at writing itself and come to understand your subject more fully.
In the writing example, it looks like this:
- Turning a vague thought into sentences
- Summarizing complex content simply
The heart of CLT seems to lie precisely in this germane load.
Good Load, Bad Load
In strength training, you increase the load on the target muscle and reduce the load from unrelated stimuli by treating them as compensation. If you design knowledge work the same way, staying conscious of which part you are stimulating, it should help you improve.
By the definition of cognitive load, the ones you can adjust are extraneous load and germane load.
The positive direction is to lower extraneous load and raise germane load. The negative direction is the opposite.
The following addresses the problem of lowering germane load: