The fundamental understanding of Cognitive Load Theory is that there exists a limit upon our cognitive capacity and that once we exceed that capacity our ability to learn is impeded. This limit is a construct of our ‘working memory’ which can be shown to have limits on the number of items it may contain and the length of time for which items are retained without renewal. For permanent learning to occur we must move items from this working memory into our long-term memory that for all reasonable purposes is limitless and permanent. As a group of professionals who are interested in learning how we may ensure our students are functioning within the limits of their cognitive load, how we may maximise the efficiency of this transfer to long-term memory is of great relevance.
As a theory to explain the relationship between our mental capacity and learning the history of cognitive load theory has its roots in the 1979 research of Moray who put forth concepts of mental load. By 2003 when Mac-Donald published his ideas on the topic the concept had been expanded and models from the world of computing provided useful metaphors. Working memory was equated with a computers random access memory (RAM) and long-term memory with hard drives and discs (or at the time possibly tapes or even punch-cards) Mac-Donald fostered the notion that mental workload is more than just the quantity of processing required for a task and that we need to consider the nature of the tasks and the interactions between elements. Mac-Donald included aspects specific to the individual learner such as their ‘self-schemas for learning’ and the perceived relevance of the task; ideas not typically included in contemporary models of Cognitive Load Theory. The present model is largely a result of John Sweller and his collaborators and is referred to as the ‘Triarchic model of Cognitive Load Theory’.
The triarchic model identifies three cognitive loads that impact the efficient formation of schemas. Extraneous cognitive load are those not directly required to master a task and have a negative impact on schema formation, reducing these is desirable and can be achieved through efficient design. Intrinsic cognitive load is that which is inherent in the task and for the most part cannot be reduced. Tasks with high intrinsic cognitive load are by nature more complex for an individual and in the long term are managed through equally complex schema. Germane cognitive load refers to the mental resources devoted to the efficient formation of schemas and is seen to have a positive effect on learning. In any task it is desirable to have sufficient load available for handling germane cognitive load as this will result in learning through the formation of schemas in long term memory.
Intrinsic Load is that which is inherent to the task at hand and is generally considered to be irreducible by adjustments to instructional methods. When we are first engaging with a concept and have limited relevant schemas to draw upon the intrinsic load of a task will however be higher than we have experience to draw upon. An example may help to describe how this works. Imagine the task of learning a new language. To begin with each word is a new piece of information that requires processing within working memory. If the language uses a set of symbols that are new to you, each symbol will require processing. The lack of relevant schemas for the building blocks of this new language mean that the intrinsic cognitive load will be large and a sensible instructor will aim to present you with small chunks. As you develop schemas you are able to move from letter sized chunks to words and sentences and with time the size of each chunk that you deal with expands. The intrinsic load in this instance is managed by understanding the size of the chunks that may be dealt with but there is a limit to how a task may be broken down and maintain relevance.
The language task above is useful as an illustration but it can be misleading too as it partly confuses intrinsic and extraneous loads. Intrinsic Load is best seen as the cognitive load required for a task as it is presented or as it must be dealt with. 'Intrinsic load can, therefore, be estimated 'by counting the number of elements that must be considered simultaneously in order to learn a particular procedure" (Plass, Moreno & Brunken 2010) Solving a mathematical problem will involve multiple elements being processed simultaneously and reducing the number of elements is not always appropriate or possible. As experience is gained and appropriately complex schema are formed the intrinsic load of many tasks will reduce as the multiple elements of the task come to be seen as one. When we first learn to drive we are faced with a task comprised of multiple elements that must be dealt with simultaneously in working memory, the intrinsic load is high. As our skills develop and our experience grows we move from driving as a task with multiple elements to the automated application of relevant schemas accessed from our long term memory and intrinsic cognitive load is reduced.
Learning to drive is an effective model for understanding the part played by Extraneous Load. When we are first learning to drive and the intrinsic cognitive load is high our progress is rapidly stopped by unexpected circumstances. A new intersection, higher than usual traffic volume, a different vehicle or distracting passenger can all be enough to trigger cognitive overload. While such distractions are often unavoidable they each bring a cognitive load that is extraneous to the task of driving. This extraneous cognitive load is the rationale behind banning the use of mobile phones by drivers. Extraneous cognitive load is that which is not essential to the task or is added by the manner in which the task is designed or presented. For the teacher understanding how the design of a task can add to extraneous cognitive load and thus inhibit learning is essential.
One element that may add to extraneous cognitive load is the manner in which information is presented particularly when multiple modes of presentation are combined. This is a key piece of the design of instructional presentations that can be managed by aware educators to reduce extraneous cognitive load. In 2008 Richard Mayer presented five principles of multimedia presentations that would reduce extraneous processing and thus cognitive load. Mayer recommends for the reduction of extraneous material such as the removal of irrelevant stimulus materials not directly relevant to the task (coherence). Mayer uses the example of a video about lightning interspersed with sensational clips of lightning. The added video while exciting to watch was found to distract the learner from the core learning. Highlighting of essential material to draw attention and focus to what is most important to the task may reduce extraneous cognitive load when it is not possible to remove distracting items (termed ‘signaling'). Not doubling up on written text and narration as is common when a presenter reads a PowerPoint slide to an audience while expecting them to read along or by adding subtitles in the same language as the audio was found to add to extraneous cognitive load. (Mayer refers to this as ‘redundancy'). Placing words and images in close relation to each other so that the connection is clear and the user does not need to search or even shift their gaze between the two items reduced extraneous cognitive load (termed 'spatial contiguity'). The largest effect Mayer discovered was from simultaneous presentation of visuals, animations or video with verbal narration (temporal contiguity). Having learners watch a film and then listen to an explanation of its content would add to extraneous cognitive load according to Mayer’s temporal contiguity theory.
In the triarchic model of Cognitive Load Theory the third influence is Germane Cognitive Load and while adding to the overall load it has a positive effect on learning. Germane Cognitive Load is that which results from dedicating resources to the formation of schemas. As the formation of schemas is the goal of learning and their effective use reduces cognitive load dedicating mental resources to their efficient formation increases the efficiency of learning. In theory reduction in extraneous load achieved through effective instruction design should free cognitive resources that then become available for application towards intrinsic and germane cognitive load. Assuming an appropriate overall cognitive load any resources not occupied by intrinsic cognitive load or wasted on extraneous cognitive load should be automatically devoted to germane cognitive load and subsequent schema formation.
Strategies that are germane to the formation of schemas may have a positive effect on learning. Such strategies may include the use of mnemonics, metacognitive strategies and reflective practices. 'Self-regulated learners are able to set more specific learning goals, use more learning strategies, better monitor their learning, and more systematically evaluate their progress toward learning goals than their counterparts' (Boekaerts, 2006 cited in Plass, Moreno & Brunken 2010). Used appropriately such strategies should speed the formation of schemas associated with the learning task while not placing excessive cognitive load on the learner. Care in the use of such strategies is called for however. When learning musical notes the use of a mnemonic such as F.A.C.E. for the letter names of notes in the spaces of the treble clef may assist a novice but requiring an expert to recall this as they play could hinder performance. A similar effect has been observed in mathematics where students are required to show working. For many mathematicians this habit breaks a complex multistep problem into manageable steps each with its own schema. For some advanced mathematicians such a requirement hinders performance, as they are utilising schemas that allow them to manage even such complex equations as a single chunk.
There is much still to be understood about cognitive load and the formation and use of schemas. As we increasingly value the ability to quickly learn, unlearn and relearn, understanding how the process of schema formation and reformation occurs is of increased value. Does the inclusion of problem solving tasks, thinking strategies, critical reflection and creative processes result in schemas that are more flexible and suitable for adaptation to new learning than more traditional methods? How might our increasing understanding of neural plasticity inform our understanding of how the brain forms and makes use of schemas? How might the use of learning scaffolds influence schema formation and reuse for learning in new scenarios? What are the strategies employed by efficient learners in the process of schema formation and in what ways might their schemas differ from those created by less efficient learners? Understanding these things will allow us to more effectively target our efforts as learners and teachers ensuring the cognitive load theory has a valuable role to play.
This introduction to ‘Cognitive Load Theory’ is intended for educators as a basic introduction only. If you wish to explore the mechanics of this further I suggest you begin by reading ‘Cognitive Load Theory’ edited by Jan L. Plass, Roxana Moreno and Roland Brunken
Plass, J., Moreno, R., & Brünken, R. (2010). Cognitive load theory. Cambridge: Cambridge University Press.
Mayer, Richard E. "Applying the Science of Learning: Evidence-based Principles for the Design of Multimedia Instruction." American Psychologist 63.8 (2008): 760-69.