Understanding Cognitive Load

Cognitive Load Theory

Cognitive Load Theory (CLT) is a framework that explains how the human brains process and store information. CLT can help teachers to better understand the limits of their learners` cognitive capacities and how to design lessons and materials to optimise learning.

CLT is based on a number of widely accepted theories about human memory. Namely:

1. Working memory and Long-Term Memory are separate stores

2. Working memory has a limited capacity of about four chunks

3. Long-term memory organises information in the form of schema

The source of cognitive load can be:

Intrinsic Load

This is related to the inherent difficulty of the material. Some concepts and tasks are easy for learners (e.g. calculating the value of S), while others are more inherently challenging (e.g. describing how a researcher would minimise the risk of a Type I error in their study). The past experience of the learner will factor into the intrinsic load. For example, an experienced psychologist or statistician will experience less intrinsic load when discussing inferential statistics than a novice.

Extraneous Load

This is related to how learning takes place and how material is presented. This is what teachers have most control over how we teach can be helpful or harmful to learning. We want to minimise extraneous load as much as possible as it detracts from the learning. That means forget the bells and whistles, and keep it simple, stupid.

Germane Load

This is what we want to maximise. Germane load is related to the processing of new information and organising it by transferring it into our long-term memory. Long-term memory organises information in the form of schemas, but this process requires working memory to actively make connections between the new information and previously learnt information. The aim for learning is to make our schemas more and more complex and interconnected. This aids learning because one schema, with all its informational complexity, only constitutes one chunk of information in Working Memory. This frees up space for the processing of other information.

Cognitive Overload

One key principle of CLT is that working memory has a limited capacity for processing information, believed to be around four chunks. If this capacity is exceeded, learning is impaired. This is known as ‘cognitive overload’.

To avoid cognitive overload, it’s important that teachers minimise extraneous cognitive load and ensure that the intrinsic cognitive load of the material is appropriate for the students’ level of expertise.

Minimising Extraneous Load

Notes and Slides

The more irrelevant and distracting information you have on a slide, the less students will remember the relevant information. Forget the animations and the frivolous pictures: Less is more. Likewise, when explaining a new concept, forget the anecdotes unless this is what you want them to recall. When teaching the Memory topic, I’ve learned to ensure any studies I ask students to participate in in lessons are near-perfect replications of the original research. Too many times I’ve had students recall details about a fun memory activity we completed in class, rather than the actual research they need to know for exams.

Diagrams

Diagrams are a helpful tool to explain difficult concepts to pupils – if done right. If pupils need to switch their attention back and forth between the text and the image, their working memory will be overloaded. Diagrams must be integrated and logical. Below are two examples. While both diagrams identify and describe endocrine glands, hormones and their function, diagram 2 is much easier to follow as the information is integrated within the diagram, whereas in diagram 1, pupils need to search back and forth between the gland and it’s hormone and function, increasing extraneous cognitive load. It’s important to review the visual aids we present to pupils to ensure they help rather than hinder learning.

Distractions

Working Memory will be overloaded if pupils need to listen and read at the same time, or if they are listening to the teacher explain a process while also taking notes or working on the problem for themselves. Pupils should only be attending to one bit of information at a time, not splitting their attention between two or more. Providing pupils will the notes in advance will help ensure they listen when they need to.

Key Terms

Students should be confident with key terms before moving on to more difficult concepts. If the allocate their cognitive resources to remembering what a key word means, they won’t be able to process new material. Ensure pupils are well rehearsed in defining and using key terms ahead of time by providing them with a glossary (and also just good practice for EAL and SEN learners). At the beginning of each topic, my pupils are given a checklist of key terms and definitions which are revisited at the beginning of the relevant lesson.

Make Connections

Encouraging pupils to think critically about the material and make connections to their own prior knowledge helps to increase germane load and facilitate deeper learning. Discussions, debates and mind maps are helpful for making this happen. For example, in the AQA Attachment topic, many of the key studies (Lorenz, Harlow, Hazan Shaver, etc.) can be used to support or contradict Learning Theory and Bowlby’s Monotropic Theory. Helping pupils make these connections as you go will aid them in embedding stronger memories. The mind map below shows the links between topics (green = evidence supports, red = evidence contradicts).

Retrieval Practice

It’s important to create opportunities for students to recall information they’ve previously learnt, particularly if it’s relevant for learning new material. Each of my lessons begins with a quick retrieval exercise on whiteboards. Often this follows the ‘one thing learned last lesson/last week/last topic/last year’ format, but other times involves multiple-choice quizzes or drawing challenges (e.g. draw a diagram to represent biological explanations for OCD).

By using these strategies, teachers can help to optimise the cognitive load imposed on students to create more effective learning experiences.