Optimizing Cognitive Load in eLearning
Did you know that people can only store around seven items in short term memory? This matters to instructional designers and instructors because information has to pass through short term memory before learners can master it. Learning is most effective when we can maximize the mental resources learners are devoting to learning. Cognitive Load Theory provides several strategies we can use to optimize our learners' ability to learn.
Cognitive Load Theory
Understanding how the human brain processes learning begins with understanding human memory. We have two types of memory: short-term memory and long-term memory. Short-term memory, which is sometimes referred to as working memory, is like a computer's RAM. It holds recently accessed information, like the last comment in a conversation or a topic you're actively thinking about, for a few seconds or minutes. Information in short-term memory is easy to recall, but it doesn't stay long. Some information is transferred into long-term memory, which stores and organizes older data. When learning something new, we start by loading new information into our working memory. From there, we process it, adding context and structure, to form something called a schema which is stored in long-term memory.
Creating an effective schema can make intensive demands on our cognitive resources. For example, several pieces of related information may need to be stored and analyzed in short-term memory. Since short-term memory is a limited resource, learning is most effective when it is focused on processing material necessary to what is being learned.
This brings us to Cognitive Load Theory. Cognitive load can be described as the number and complexity of things occupying a person's short-term or working memory at a given time. When unrelated or overly complex presentations take up room in one's short-term memory, it makes it harder to process the information necessary to learning, and learning becomes more difficult. Cognitive load theory is about making learning easier by simplifying the presentation of new information and limiting the demands on short-term memory, thereby freeing learners to direct all their mental resources to mastering the learning.
Learning itself generates cognitive load, so the goal with Cognitive Load Theory is not so much to reduce cognitive load as to optimize it. There are three types of cognitive load.
Intrinsic cognitive load
This cognitive load is a factor of the complexity of the material being learned. Some things are easier to learn, producing less cognitive load, than others. While some intrinsic cognitive load is unavoidable, instructional designers can reduce it by thoughtful presentation of complex subjects. For example, when complicated processes are broken down and presented step-by-step, learners only need to understand one step at a time. Learning a single step engenders less cognitive load than learning the whole process at once, reducing the risk of cognitive overload.
Extraneous cognitive load
This is extra or irrelevant cognitive load. It can be caused by outside factors and distractions, or by poor presentation of learning content. Extraneous cognitive load hinders learning and should be eliminated, as far as possible.
Germane cognitive load
This is the cognitive load generated by the learning process itself.
Reducing intrinsic load and eliminating extraneous load free mental resources for handling germane cognitive load, which is where learners learn. If unnecessary loads are too high and "cognitive overload takes place, then learners will be more likely to make errors, not fully engage with the subject materials, and provide poor effort overall."
Strategies for Optimizing Cognitive Load
1. Include only "need to know" information
When building eLearning, we often encounter content that is relevant but not essential. Around here, it's called "nice to know" information, and it's excised ruthlessly. "Nice to know" information takes up room in learners' working memory, displacing "need to know" information and increasing the risk of cognitive overload. To ensure all content is necessary, build effective learning objectives and include only the content needed to meet those objectives.
The need to know/nice to know distinction doesn't just apply to text and audio scripts. It's also true for graphics, particularly that scourge of eLearning, the decorative graphic. Decorative graphics may be pretty and may even be somewhat relevant. They're also information that's not needed for learning, which means they impede your audience's ability to grasp the content you're trying to present. If you're expected to include graphics in your eLearning, check out some of the meaningful graphic suggestions in Successfully Incorporating Visuals into Online Training.
2. Avoid repetition
Repetitive or redundant information is another unnecessary consumer of working memory, "partly because it becomes more challenging to pay attention to repeated information, but also because the learner is looking for a slight difference that might explain the apparent repetition." - Tom McDowall
Narrating onscreen text word for word is a common form of redundancy in eLearning. Asking learners to process information twice does not reinforce it, it just adds extra effort. More effective onscreen display options include highlights or summaries and meaningful graphics. I recommend providing both text and audio options for accessibility, but this text should be available through a link or download, not as the default display.
3. Simplify the presentation of material
As mentioned earlier, chunking the material to be learned, or presenting it step by step, reduces the intrinsic cognitive load required to master it. Learners need only focus on one item or step at a time and should not move on to the next section until they are sure of the current one.
Another useful strategy for simplifying complex material is the worked example or case study. Novice learners exploring how to solve a problem or apply a new behavioral strategy are presented with an example that is worked through, step by step, showing how to complete the task. Providing the solutions removes the stress of having to come up with an answer. Additionally, demonstrating the process helps to form a schema and transfer the information to long-term memory.
There is a potential drawback to using these techniques. If some of your learners are already familiar with the material, step-by-step explanations and worked examples can increase their cognitive load and cause confusion. As always, it's essential to know your audience and determine their level of expertise before developing learning content. When you have a mixed-level audience, consider linking to worked examples and step-by-step instructions so they're available to novice learners and can be ignored by expert learners. Adaptive learning is also effective in this type of situation.
4. Integrate the information presented
Cognitive Load Theory posits that we have separate channels for audio and visual information. Extraneous cognitive load is increased when more than one set of information is presented on the same channel at the same time. For example, you've probably seen a diagram of a device labeled with letters combined with a legend showing which part each letter refers to. The two visual sources of information, the diagram and the legend, combined with the need to keep switching between them, significantly increase cognitive load. It's much easier to understand when the information is integrated, and the parts are labelled on the diagram itself.
Real-life tasks often require learners to use information that isn't integrated. Have you ever had to show learners how to look up data in reference material and use that data to perform a calculation or complete a task? I have, and I used to expect learners to look up the data the first time they tried a sample calculation. A more effective strategy is to:
- Provide a worked example
- Ask the learners to complete sample calculations with all data provided
- Add the task of looking up the data only after the learners have mastered the calculation
5. Minimize the mental resources required to access learning
Extraneous cognitive load doesn't just come from the learning material. Many people try to complete eLearning while keeping an eye out for their subway stop, figuring out how to navigate the learning module and parsing the complicated language it's written in. Instructional designers can't necessarily do anything about the subway, but we can reduce the cognitive load produced by the technology and language we use.
Clear, concise, and straightforward language is always a boon to learning. Even if all our learners are capable of understanding post-graduate level language, why should they have to? Simple language can usually convey the message with less time and effort.
With technology, familiarity is the key. When possible, stick to programs that are standard for the organization so learners will already know how to use them. If it's necessary to use a new program or interface, provide an overview or tutorial that's separate from the learning content so they don't have to contend with learning the software and the content at the same time.
Cognitive Load Theory offers valuable strategies for eLearning designers. Learning becomes more efficient when we eliminate unnecessary and redundant information, simplify our content, integrate information and remove barriers to learning.
Sarah is an Instructional Designer at BaseCorp Learning Systems and is currently completing a PhD in Educational Technology. Her research focuses on implementing competency-based learning systems in all types of organizations. When she doesn't have her nose in a book you can find her at the gym, on the ice, on the ski hill, drinking wine or in a coffee shop … with her nose in a book.