When I first started working as an eLearning instructional designer I became interested in the learning process and how people learn. I figured that if I knew more about information processing and learning, I could hopefully design more effective courses. I came across a book called Efficiency in Learning: Evidence-Based Guidelines to Manage Cognitive Load by Ruth Colvin Clark, Frank Nguyen and John Sweller. In this book I discovered, among other things, Cognitive Load Theory (CLT) which is based on studies of human cognitive architecture – how we process and organise information.
In our brains, we have two types of memory. One is our working memory, which we use to process new information. The capacity of our working memory is quite limited so it can only handle so much before it becomes overloaded. The second is our long-term memory, which is where we store information from our working memory and where we retrieve that information from later. Within our long-term memory, information is organised into schemas, which are organisational frameworks of storage (like filing cabinets). Not exceeding working memory capacity will result in greater transfer of information into long-term memory.
CLT proposes that there are three types of cognitive load:
- Intrinsic: this is the level of complexity inherent in the material being studied. There isn’t much that we can do about intrinsic cognitive load; some tasks are more complex than others so will have different levels of intrinsic cognitive load.
- Extraneous: this is cognitive load imposed by non-relevant elements that require extra mental processing e.g. decorative pictures, animations etc. that add nothing to the learning experience.
- Germane: these are elements that allow cognitive resources to be put towards learning i.e. assist with information processing.
The three types of cognitive load are additive so according to the theory, for instruction to be effective:
Intrinsic load + Extraneous load + Germane load < Working memory capacity
To assist learners in transferring information from their working memory to their long-term memory, we need to present the information in such a way that it reduces extraneous cognitive load (non-relevant items) and, if possible, increases germane cognitive load (items that assist with information processing).
Note: I’ve found that much of the literature tends to focus on reducing extraneous cognitive load.
Mayer and Moreno (2003) conducted research into ways to reduce cognitive load in multimedia learning. Their research, built on CLT, was based on three assumptions:
- Humans possess separate information processing channels for verbal and visual material (Dual Channel).
- There is only a limited amount of processing capacity available via the visual (eyes) and verbal (ears) channels (Limited Capacity).
- Learning requires substantial cognitive processing via the visual and verbal channels (Active Processing).
They found that designers should do the following to assist learners in processing information:
- Present some information via the visual channel and some via the verbal channel.
- Break content into smaller segments and allow the learner to control the pace.
- Remove non-essential content – this includes background music and decorative pictures that don’t add value.
- Words should be placed close as possible to the corresponding graphics.
- Don’t narrate on-screen text word-for-word.
- Synchronise visual and verbal content i.e. don’t place them on separate screens.
As instructional designers, we need to be aware of the cognitive requirements our designs impose and ensure that our learners can meet those requirements. We must also ensure that all aspects of our design focus on adding value to the learning experience.