Designing for Cognitive Load

Cognitive load theory is one perspective on learning that can be applied to teaching in this unusual time. The theory sees working memory — the part of the mind that temporarily stores and manipulates information — as a constraint on learning, because it can only manage a few pieces of information at once. Placing a load on working memory is like trying to push water through a pipe with a constant diameter; you can shove only so much water through the pipe at any given time at a given pressure. If the water’s pressure exceeds what the pipe is able to withstand, you get a flooded basement.

What is the square root of 1,137?

There are three types of cognitive load: intrinsic, germane, and extraneous. Intrinsic load represents the essential actions that occur when learning information that is specific to a topic or task. The load varies according to the information’s inherent level of difficulty for the learner, which makes it partially a function of prior learning: the more one has practiced using the information, the less the effort that needs to be expended the next time it’s encountered. Tying shoelaces requires our full concentration when we are in kindergarten; as adults we perform the task almost automatically and can attend equally well to other cognitive demands at the same time.

Germane cognitive load consists of the work of converting the information in working memory to permanent knowledge, or what the psychologists refer to as a schema. You can think of germane cognitive load as the physical actions of a bank employee storing your shoebox full of cash in the bank’s vault for you to retrieve when needed at some future time. Germane cognitive load is the mental effort that occurs when something is actually “learned.”

Extraneous cognitive load is generated by environmental factors, such as the learner’s emotional state and, most importantly for the readers of this blog, how information is presented. These factors do not make essential contributions to learning and can in fact impede the working memory’s performance. If I am teaching students a melody from Phantom of the Opera, I can show them the musical score or I can point to images of different instruments while talking about the notes those instruments play. The former is a far more efficient method of instruction than the latter.

Can’t ever unsee

Therefore, for any learning activity, the intrinsic load should match the learner’s level of experience and the extraneous load should be minimized. This leaves the working memory with enough resources to handle a germane load that is sufficient for learning.

For example, an instructor might describe Europe’s Triple Entente and Triple Alliance in an international relations course to help students understand the balance of power. But if this description is full of highly-technical vocabulary that is unfamiliar to students, or if it is communicated in the midst of a lesson on a different topic that students perceive as unrelated, the extraneous load is high and their ability to learn the concept decreases.

So how do we identify elements of our teaching that generate extraneous cognitive load? One tried and true method is to have students or colleagues observe your teaching. In the era of Zoom, the observers don’t even need to be from your own institution. Are they able to get from your teaching what you think your students are getting?

Also ask yourself whether how and what you’re teaching is truly critical. This semester I’m teaching an undergraduate course on the Middle East. I’ve found that online synchronous teaching eats up a lot of time that I would otherwise use to communicate historical details, so I’ve had to really pare down my audio-visual presentations. Instead of immediately diving into specifics that can be found in a book, I start each lesson by asking students a broad question that pertains to their current knowledge, send them into breakout rooms to discuss it, then write a some of their comments on a screen-shared whiteboard when class reconvenes. This activity places the lesson into context so that they are less likely to perceive the information that follows as a series of disconnected facts. I then touch on only a few basic underlying events or processes. Students can examine the topic in more detail on their own time, using the signposts I’ve provided.