Memory

Introduction

Memory is our ability to store and later recall our experiences. It is essential to our survival as it enables us to adapt our current and future behaviour based on what we have learnt in the past. Learning can therefore be thought of as the process of laying down memories that may be useful in the future. There appears to be no limit to the amount of memories that can be permanently stored in the human brain but that doesn't mean that we remember everything. Nor would we want to! In fact, we only permanently store a very small amount of our daily memories. Most things are discarded as unimportant, particularly routine and familiar experiences. Even things we want to remember are often forgotten and this is explored below. There are a number of different specialist memory components suggested by researchers but, for the purpose of this article, we will limit ourselves to a description of memory in the short, medium and long term.

Understanding Memory

We have different memory capacities and abilities depending on how long we are trying to remember something. Some things we only need to remember for a few seconds whilst others we want to hold onto for a lifetime.

Short-term Memory

Short-term memory enables us to hold on to a wide range of sensory and thought products for a few seconds. For example, whilst reading this sentence you store individual words until you can make sense of its meaning. Once understood the words are forgotten.

Long-term Memory

Long term memory is our permanent store and enables us to remember things we learnt or did many years ago. It is believed that once committed to long term memory this is permanently fixed. Over time we may struggle to recall this memory but this may a problem in 'finding' and retrieving rather than a loss of the memory. However, the more we tend to recall a memory the more likely we can 'find' it again when we want it. The cliche 'If you don't use it, you lose it.' may have some truth with memory.

'Something in between' memory

Between short and long term memory is a medium memory generally known as episodic memory. This memory enables us to remember recent events: where we have been and what we have done. E.g. like what we ate for breakfast this morning. These memories fade over a number of days unless committed to long term memory.

Memory and Learning

Each of these three memory systems is crucial for effective learning and it is perhaps surprising that initial teacher training does not focus more on understanding the mechanisms of memory. For schools, this lack of knowledge on how memory works leads to a loss in learning potential. Clearly, children do remember things and make good progress but greater awareness of memory could improve this further. In 1885 a German psychologist called Hermann Ebbinghaus formulated a theory of forgetting which attempted to describe how memories fade over time. He recognised how factors such as sleep and stress affected memory retention. He also proposed the concept of overlearning, repeatedly going back over the same learning to consolidate memory.

Forgetting

Today we know more about the mechanisms by which we create permanent memories that in Ebbinghaus's day and his work on forgetting and overlearning remains valid. His forgetting curve applies to all memory and to adults as well as children. For adults it is particularly pertinent to training courses not just in education but in all areas of employment where most participant quickly forget what they learn. Teachers will also recognise how students appear to have understood and learnt in one lesson and then frustratingly have no idea in a subsequent lesson. So what happened to their learning? When they could remember the 'learning' it will have been stored in their episodic memory. This is a temporary store located in the hippocampus. Here memories remain until they are passed into long term memory or fade away. Various factors impact on whether a memory becomes consolidated or forgotten including:

Information Overload

Too much sensory input in a day can overwhelm our memory systems. This can include both too much learning in a lesson, in a school day and the impact of too much TV or playing computer games.

Sleep

Research suggests that consolidation of memory occurs towards the end of a sleep cycle. Clearly children (and adults) who do not get enough sleep may struggle with the laying down of permanent memories. This can have a huge impact on their ability to progress in learning.

Stress

Stressful events will tend to dominate our thoughts and will be prioritised over less 'critical' learning. Children that are experiencing abuse, trauma or otherwise stressful lives will be less able to focus on learning and make long-term recallable memories. Stress hormones also interfere with sleep which in turn reduces memory consolidation. The identification of vulnerable students in school is thus vitally important.

Overlearning

Revisiting learning whilst it is still remembered reactivates the memory trace and reinforces it. All children benefit from opportunities to revisit previous learning in order to consolidate their understanding and recall of facts and skills. Children who struggle with acquiring learning will make progress if exposed to enough overlearning.

You may also be interested in the following pages:

Short Term Memory

Working Memory

Strategies to support weak working memory

Back to list of Development Articles