Limited Load

Image by Bernhard Stärck from Pixabay

I probably don’t need to tell you that your brain is limited. Most of us know this all too well and we’ve crafted identities as adults that protect us from the challenges that exposed us as children. Adults often get to choose their challenges, unlike children. You’re not a math person, or a science person, or a literature aficionado, a history buff—so you stay away from those areas. You’re not good at them, so why bother?

If this is you, you’re missing out on opportunities for personal growth and even epiphanies of discovering latent abilities you didn’t know you had. You’re “protecting yourself” like the picky eater who never tries new foods because they look or sound scary and therefore misses out on the banquet table of regional and national cuisines.

 Most learning limitations are due to defective learning strategies.

There are two ditches to avoid on the road to learning. One is cognitive overload where we ask our brains to do something strenuous we haven’t prepared them to do. The other is rote learning of trivial information. This is under-loading the brain to the point that motivation to learn withers because curiosity is dead on arrival.

Cognitive Load Theory is the title of an important book that was published in 2011. The authors define the topic this way, “Cognitive load theory consists of aspects of human cognitive architecture that are relevant to instruction along with the instructional consequences that flow from the architecture.” (Sweller, p. v) The most limiting elements of our cognitive makeup relate to working memory.

Working memory is where all learning originates.

Working memory is where all learning originates. It is the place where sensory inputs that convey novel information are brought together with ideas retrieved from long-term memory. Working memory appears to be limited to 4 ± 1 items at one time, down from the 1956 estimate of 7 ± 2. It seems the nature of the items makes a substantial difference. Working memory is also extremely volatile with items disappearing within less than 20 seconds unless consciously rehearsed.

It is, therefore, striking that “The most important characteristics of long-term memory are that it has no obvious capacity or duration limits, in stark contrast to the severe limits of working memory when dealing with novel information.” (Sweller, p. 48) All long-term learning has been forged first in the working memory, so there are ways to be productive within its limitations.

All cognitive tasks must be trimmed to fit within the capacity of working memory.

Ideally all loads extraneous to the actual learning task will be eliminated. This includes environmental distractions, attempts at multi-tasking, etc. It also includes teachers with heavy accents, poor enunciation, or voices that are grating. There are many others. Take a look at your environment!

What is not often appreciated is that curriculum designs often have significant amounts of extraneous load built in. The prototypical jargon-heavy presentation compounds confusion by using an unfamiliar vocabulary to express unfamiliar ideas.

Continuing on the design level, Mayer’s redundancy principle predicts that speaking the words on a text heavy projected PowerPoint slide will create a conflict in the viewer of whether to read the slide or listen to the speaker. This is not just a faux pas, but an extraneous load element that is all too common. You can see this bifurcation if you follow “words” on the left of this figure from Mayer and Johnson:

Richard E. Mayer and Cheryl I. Johnson, Journal of Educational Psychology 2008, Vol. 100, No. 2, 380–386.

Mayer and Johnson articulate four principles for effective multimedia instruction that can help you avoid extraneous load in your presentations.

 “1. The multimedia principle—you use both words (as spoken text) and pictures (as animation or a series of still frames).

2. The coherence principle—you minimize any extraneous words or pictures.

3. The modality principle—you present the words as narration rather than as on-screen text.

4. The temporal contiguity principle—you present the narration at the same time the corresponding event is depicted in the graphics.”

Extraneous load in PowerPoint is humorously illustrated here:

Extraneous load is deeply embedded in some instructional approaches. Open-ended discovery learning is a frequent offender because it does not provide sufficient context to direct problem-solving to productive knowledge domains. Likewise, mathematically intense problem-solving that does not first establish the conceptual framework that provides the rationale for the computational procedures creates unnecessary cognitive load. This is quite common in physics instruction.

Image by Elchinator from Pixabay

Intrinsic load sounds like it can’t be altered, but that isn’t entirely true. Motivation to learn and attention to the task are variables that affect intrinsic load. That means cognitive load can vary for the same person. We all have our bad days! The cognitive load associated with a given task can also vary from person to person based on prior knowledge.

Long-term memory is mostly occupied by schema (also known as a chunk). A schema is a group of ideas that are logically related and that have been bundled together with an identifying label in long-term memory. A schema counts as one item in working memory regardless of how many concepts are in the bundle. Schema formation is the major strategy that makes space for handling additional items in working memory.

A schema is a group of bundled ideas that are logically related.

A person with pre-existing schemata [that’s the plural] relevant to the task is in a much different place than someone without them. This should serve as a cautionary note to teachers since they possess schemata that make daunting learning tasks quite manageable and even trivial. This has been wryly termed “the Curse of Knowledge.” (Heath, p. 278)

 “The Curse of Knowledge. . . once you know something, it’s hard to imagine not knowing it.”

The most obvious way of reducing the intrinsic cognitive load of a task is to systematically build the underlying conceptual framework for the task. You build concepts first and then smaller chunks (some call them sub-schema) and then chunks (schemata) of increasing complexity. These stages of learning call for increasingly abstract thought, but all of them fit within working memory. They are like flights of stairs.

Teachers need to break down complex learning tasks into mind-size chunks that fit within the working memory of the average student. This involves unpacking complex ideas and creating learning tasks that stretch, but don’t break, the typical student. These tasks should have optimal cognitive load.

Photo by Vlada Karpovich from Pexels

Optimal load, why not light or minimal load?

Brains work best with learning challenges that are motivating to the student and are within reach with diligent effort. Such challenges result in understanding as the fruit of the cognitive grappling that has gone on in the working memory. Understanding is a reward of its own—it’s a lightbulb moment—and it results in long-term memory because “it makes sense.”

Unpacking presupposes that the ideas will eventually be repacked into evolving schemata. It is important that this bundling be as intentional as the unbundling was. The relationship between the component concepts in a bundle and between bundles (subschema) and the overarching schema that results must have the right logical structure.

Students who understand where they are in the journey can reconstruct the path that led to the multiple breakthroughs of understanding. Traveling that path in the future can also lead to additional insights resulting in even more powerful schemata. In contrast, learning tasks that have few elements and easily fit in working memory are insufficient to create lasting learning or to motivate the student because they are trivial and there is really nothing to understand.

An example of the trivial is “Rock, Scissors, Paper.” Most kids just state as facts “rock beats scissors,” “scissors beat paper,” and “paper beats rock.” The missing element is why there is a winner in each pair. What is the basis of paper beating rock for instance? Is there something to understand here?

A bit more sophisticated, but still largely trivial is memorizing the chemical symbols. For most people this is raw memory with rewards only when you get to the logic that undergirds the periodic table. I know you can go pseudo-linguistic by revealing that Na stands for natrium which is the same as what we call sodium, but that merely adds a layer to something that “just is.” Much the same thing can be said for the assignment of labels to the letters of the English alphabet. The symbols are arbitrary, but you have to memorize them as part of the process that leads to reading.

"Surely You're Joking Mr. Feynman" by Michael Graham Richard is licensed under CC BY 2.0

Nobel Prize-winning physicist, Richard Feynman was known as “The Great Explainer” because he knew how to simplify abstract complexity in pursuit of building deep understanding. Feynman avoided complex jargon and used accessible physical analogies to reduce cognitive load. He never exalted his knowledge when teaching beginning students. Instead, he famously said that if an idea couldn’t be properly explained to a first-year student, it was because you (and possibly the scientific community) didn’t really understand it and therefore couldn’t make it accessible.

Feynman was a member of a commission that investigated the space shuttle Challenger disaster. Here he is zeroing in on the behavior of the infamous O-rings at low temperature:

If you’d like to view more of Feynman explaining, check out this collection:

Build your knowledge from the ground up; concept-by-concept; chunk-by-chunk until you build schemata that are up to solving the cognitive problems that are important to you. Long-term memory will follow automatically!

“Cognition is organized in a structured series of attentional episodes, allowing complex problems to be addressed through solution of simpler subproblems.”

John Duncan

References

John Sweller, Paul Ayres, Slava Kalyuga, Cognitive Load Theory, Springer, 2011.

Richard E. Mayer and Cheryl I. Johnson, “Revising the Redundancy Principle in Multimedia Learning,” Journal of Educational Psychology 2008, Vol. 100, No. 2, 380–386. DOI: 10.1037/0022-0663.100.2.380

Chip Heath and Dan Heath, Made to Stick, Random House, 2008.

John Duncan, “The Structure of Cognition: Attentional Episodes in Mind and Brain,” Neuron 80, October 2, 2013, pp. 35-50 https://doi.org/10.1016/j.neuron.2013.09.015