How can teachers consider the limitations of students' working memory in classroom environments?
What is working memory?
Working memory is one of the eight executive functions considered necessary for cognitive processes and is central to understanding the psychology of learning. Working memory is the ability to hold information in mind and manipulate it at the same time. Working memory is important because it helps us process information efficiently. When working memory is strong, we're able to pay attention to multiple things at once, remember where we left off when reading, and keep track of our thoughts and feelings.Students who struggle with working memory often find themselves overwhelmed by the amount of material they need to learn, especially in the early years of school. They may be unable to retain information long enough to complete assignments, and they may not understand concepts well enough to apply them to real-life situations.
Context for teachers
I am secondary school teacher with a background and degree in Mathematics and Psychology. Having previously been Head of Mathematics and teacher of Psychology and Physics, I am now responsible for the quality of teaching and learning across all subjects and teachers' professional development. I have found cognitive psychology and education research to be invaluable in my current role. This article will provide you with a teachers' perspective about how the findings from cognitive psychology and Baddeley's working memory model can be applied to classroom practices. Small changes to the way we teach can enable us to get the most out of our students' working memory and achieve long-term learning.
Types of Memory
According to the multi-store model of memory, we have three types of memory that are defined by the differences in their duration and capacity:
- Sensory Memory
- Short-Term Memory
- Long-Term Memory
Our sensory memory processes everything in our environment. There is too much information for us to have conscious awareness of it and it can only remain in our sensory memory for less than a second. We are constantly bombarded with information from our senses; our sensory memory works hard to filter that information and determine if it is important enough for our attention and to be granted access to our short-term memory.
When we actively pay attention to information, it enters our short-term memory where it can stay for up to 30 seconds without too much effort. There are individual differences in the capacity of our short-term memory but most people can retain between 5 and 9 chunks of information at any given time (you may have seen this referred to as '7 plus or minus 2'). Information will leave our short-term memory quickly if it is not processed in some way. We will see later that repeating information using our inner voice (subvocal rehearsal) or processing the information in a meaningful way (elaborative rehearsal) are two of the cognitive processes required to move information into our long-term memory.
If we want to keep information for longer than 30 seconds, we must move it into our long-term memory. This is where information is filed, ready for us to retrieve when we need it. New information is linked with previous learning from related topics to help us retrieve it more effectively in the future. There seems to be no limit to the capacity or duration of our long-term memory. However, having a limitless amount of information means that it can be difficult or sometimes impossible to retrieve a precise piece of information when it is needed.
Learning and Memory
If you have read any of my previous articles, you will know that I like to define learning as a permanent addition to the long-term memory that can be readily available when it is needed.
Learning is a two-stage process:
- Information is accurately encoded into the long-term memory
- Information can be accurately retrieved due to the cues associated with the new memory
For information to enter the long-term memory, it must be processed by the short-term memory. In the multi-store model of memory, the short-term memory represents a store of information; it does not consider the structure or the cognitive processes required to transfer information into the long-term memory. Baddeley developed the working memory model to address this issue and it is now considered to be an essential component to cognitive development.
The Working Memory Model
Baddeley's original model of the working memory was a multicomponent model consisting of three elements:
- Phonological Loop
- Visuo-Spatial Sketchpad
- Central Executive
Brain imaging studies and research involving patients with brain damage led to the addition of a fourth component:
- Episodic Buffer
Brain research has supported the use of a multicomponent model of the working memory by identifying four distinct areas in the brain that are associated with each component. The prefrontal cortex is home to the central executive, the phonological loop is found in the left temporal lobes, the visuospatial sketchpad occupies the right parietal cortex, and the episodic buffer is in the parietal cortex.
It is exciting to see physical evidence for a theoretical model that was originally created by observing memory performance on simple memory tasks.
The working memory is a gateway to the long-term memory. It is fascinating to study because it lends itself so well to practical interpretations that can make real differences to long-term learning and memory capacity.
I have described each part of the multicomponent model in more detail below.
The phonological loop is used to encode speech sounds and ‘hears’ your inner voice when you read text. It is used to complete verbal tasks, for language processing, and language comprehension. In the classroom, the phonological loop that is likely to be used most often. It is needed to read text, listen to the teacher and give verbal responses.
It can be used to transfer information to the long-term memory through subvocal rehearsal, repetition using our inner voice.
The visuospatial sketchpad encodes visual information, such as colour, images and location. Our visuospatial memory is part of the elaborative rehearsal process that transfers information to our long-term memory. For students, this happens when they:
- Use the positions of words on a mind map as memory aids
- Repeatedly create an image in their minds in response to a description
- Use memory training techniques such as mnemonics
- Remember key words due to their location on a classroom wall
The central executive is used to complete cognitive tasks by monitoring and coordinating the other components in the working memory. It is used for decision-making and to determine where we should direct our attention. When students appear to have selective attention, it may that the central executive is trying to control too many cognitive processes at one time.
The final addition to the working memory model, the episodic buffer, may be the most important and complex part of the model. It creates and retrieves memories of experiences and acts as an intermediatory stage between the short-term memory and the long-term memory. The episodic buffer is thought to control processes using a multidimensional code, which is how it is able to integrate information from different components of the working memory as well as the long-term memory.
Limitations of the Working Memory
Baddeley's working memory model improves our understanding of how information is processed in the short-term memory and transferred to the long-term memory. Research supports the existence of distinct components and has also been used to demonstrate the limitations of our working memory. All of the separate stores have limited capacities; when one store becomes overloaded with information, performance on memory tasks drops significantly and transfer to the long-term memory becomes much harder.
Imagine how it feels to read a passage of text when someone is talking to you. Your attention is divided and you can't focus on either one as much as you want to because your phonological loop is overloaded. As teachers, we must consider the demands being placed on students' working memory when they are in our lessons to ensure effective and long-term learning can take place.
Research Perspective: Cognitive Load Theory
Cognitive Load Theory has influenced my teaching more than any other area of psychology or CPD activity. It is concerned with maximising the efficiency of the working memory and consequently improving learning.
Although each component of the working memory has a limited capacity, the overall capacity of the working memory can be increased when two or more of the components are used simultaneously (dual coding). Information will be encoded into the long-term memory more effectively if it is processed by more than one store. This can be achieved by:
- Presenting new information as an image and narrating over it
- Annotating a diagram with text
- Asking students to make decisions about the new information
- Making explicit links to prior learning
Most importantly, Cognitive Load Theory emphasises the need to reduce all unnecessary pressure on the working memory and avoid the cognitive overload of any one store. At all times during a lesson, we should consider what we want our students to be attending to, and ensure that we are not distracting them with any redundant or distracting information at the same time. Something every teacher has been guilty of is talking when there is text on the board; these both require the attention of the phonological loop and neither will get the attention it deserves. We can avoid this problem by only talking when the board is blank or displaying images and remaining silent when there is text on the board or students are reading or writing.
Putting working memory considerations into Practice
Students, teachers and families can use Cognitive Load Theory to create environments where learning and revision can occur more effectively. Keep in mind the features and limitations of the working memory, try to use two stores simultaneously and only ever use each store for one task at a time.
- Avoid overloading one store with information
- Don’t speak when you need students to be reading
- Stop talking when there is text on the board
- Use two separate stores to present new information
- Talk when you are displaying images
- Use coloured font to show links or differences
- Make explicit links with prior learning
- Reduce unnecessary visual distractions from the front of the classroom, including posters
Educating Students About Working Memory
The working memory and Cognitive Load Theory are accessible concepts for students to understand. It is easy to demonstrate what happens when you overload the phonological loop: ask students to read a passage of writing while they repeat the word 'the' out loud. Students enjoy learning about the working memory because it explains some of the difficulties they experience during lessons and provides concrete ways in which they can improve learning.
The following advice is for students to maximise the efficiency of their working memory.
- Don’t divide your attention when you learning
- Put your phone out of sight and turn off the TV
- Listen to music without lyrics to relieve your phonological loop
- Working in silence is even better
- Read out loud to focus all of your attention on what you are reading
- Use colour and put notes in different positions on the paper to help you remember them
- Recall information rather than copying it – this will force you to pay more attention to the information
- Create an Environment to support learning by removing unnecessary distractions to create a calm and quiet place to work
Having an awareness of how our memory works and knowing the limits of our working memory can help students and teachers to make small changes to the way they work to significantly improve learning. Throughout each lesson ask yourself 'what do I want my students to be thinking about now?' and 'what part of their working memory are they going to be using?'. Answering these questions will make it clear whether you need to do anything differently to allow their working memory to effectively complete the task you need it to be doing.
I hope you have found this article helpful. If you would like to introduce your students to cognitive load theory, you are welcome to show them this short video that I produced for our students and teachers.
Connect with me @HeathfieldLearn or firstname.lastname@example.org
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