The limited capacity of working memory is a key concept in cognitive psychology and instructional design. Working memory is a temporary memory store that regulates incoming information in order to fulfill a person’s goals. It is where we actively manipulate information.
Working memory capacity is small and information in working memory is of a short duration. To accommodate these limitations, instructional designers use chunking in two ways. We decompose content into smaller chunks to avoid overloading a learner’s working memory. Alternately, we may cluster related information into larger chunks as a way to improve the capacity of working memory. Chunking can happen in either direction. See the explanations below.
In the instructional design process, the decomposition of content is typically part of a content, task or instructional analysis. We conduct this process by identifying the key skills a person must perform and then define the supporting knowledge necessary to perform the critical skills. Some people use an information processing analysis (via Dick & Carey) or action mapping (via Cathy Moore) or similar approaches. If the skill can be broken into subtasks, then a task analysis is appropriate. The important question when decomposing material is to ask, “What does the learner need to do next in order to perform this skill?”
Chunking Information for eLearning
Decomposing information is particularly important when designing self-paced instruction, like eLearning. The content has to be organized in a logical and progressive way through chunking. Chunking doesn’t only work for your typical linear instruction. It also works for non-linear approaches, such as when the learner chooses the order in which to explore various topics.
An important aspect of chunking is that the chunk is conceptually related information. Content that is conceptually related is more meaningful than randomly organized information.
How to Chunk Content for eLearning
Now that we can proudly say our working memories are basically sieves, what strategies can eLearning designers implement to overcome this? After your analysis, follow these steps.
- Step 1: Start at the highest level.
Use a chunking strategy while determining the content hierarchy of a course. Determine how modules, lessons and topics will be organized into a logical and progressive sequence. Start with large chunks of conceptually related content and use these as your modules. There are numerous organizational strategies, such as simple to complex, cause and effect, sequential, etc. See 10 Ways to Organize Instructional Content for more on this.
- Step 2: Modules into lessons into topics.
Divide modules into smaller related chunks and these will become your lessons. Continue with this process until content is broken down to the topic level. As you become more familiar with the content, fine tune the internal structure.
- Step 3: Chunk at the screen level.
When you have a solid module-lesson-topic structure, organize the content so each screen consists of one chunk of related information. Depending on how you design, this could be at the topic level, at the detailed learning objective level or at the concept level. As a guiding rule, avoid introducing multiple topics, learning objectives or concepts at one time.
- Step 4: Do a working memory check.
Throughout the process, think in terms of working memory. Do you really need to include all the content you have in front of you? If not, get rid of extraneous content. Less is more. See 20 Facts You Must Know About Working Memory.
Will the chunk of content require the learner to hold more than a few interacting pieces in memory at one time in order to understand it? If so, break it down again. Fortunately, the visuals and text in multimedia courses can lessen the demands on working memory. So can performance support assistance, such as job aids. At meaningful intervals, allow learners to integrate the chunks together using interactive and participatory activities.
What if you have lots of unrelated information?
Turn Bits into Chunks. If you have lots of unrelated facts, it’s possible that this is extraneous content and you don’t need it. If you are certain these unrelated facts need to be included, find some way that they relate to each other and connect them.
In this situation, you have to chunk information in the opposite direction. Use any strategy that turns individual bits of information into meaningful chunks. Perhaps an analogy or metaphor will work.
Working memory is just as willing to hold four chunks of information as it is to hold four bits of information. For example, you can remember four letters as well as four words. By finding ways to group together small bits of information into a chunk and you’ll help learners process and retain more at one time.
For more on this topic, see: How does chunking help working memory?
George Miller’s milestone article from 1956: The Magical Number Seven.