Memory Span and Working Memory

What is Memory?

Memory is the process of maintaining information over time.

There are three important aspects of information processing:

1. Memory Encoding

It allows the perceived item of use or interest to be converted into a construct that can be stored within the brain and recalled later from short-term or long-term memory

There are three main ways in which information can be encoded (changed):

1. Visual (picture)

2. Acoustic (sound)

3. Semantic (meaning)

For example, how do you remember a telephone number you have looked up in the phone book?

If you can see it then you are using visual coding, but if you are repeating it to yourself you are using acoustic coding (by sound).

2. Memory Storage

This concerns the nature of memory stores, i.e. where the information is stored, how long the memory lasts for (duration), how much can be stored at any time (capacity) and what kind of information is held.

The way we store information affects the way we retrieve it.

According to Miller (1956) Most adults can store between 5 and 9 items in their short-term memory.  The capacity was 7 (plus or minus 2) items because it only had a certain number of “slots” in which items could be stored.

However, Miller didn’t specify the amount of information that can be held in each slot.  Indeed, if we can “chunk” information together we can store a lot more information in our short-term memory. 

3. Memory Retrieval

It is a process of accessing stored memories. When you are taking an exam, you need to be able to retrieve learned information from your memory in order to answer the test questions. If we can’t remember something, it may be because we are unable to retrieve it.

What is Memory Span?

Memory span refers to the amount of items includes numbers, letters, or words, that a person has the ability to remember.

Short term memory refers to where we keep information that we can readily tap into and utilize. We have the ability to keep information in short term memory for an estimated 18 to 20 seconds.

The example of memory span would be the digit span.  A digit-span task is used to measure working memory's number storage capacity. Participants see or hear a sequence of numerical digits and are tasked to recall the sequence correctly, with increasingly longer sequences being tested in each trial. The amount of items that a person can correctly recall in order is the person's memory span for the particular task. For example, Child 1 memory span is 13, given that he was able to correctly identify all 13 numbers. Given that the average memory span is seven items, Child 1 scores indicate that his memory span is better than most. Memory span tests do not always ask you to recall numbers. For example, you could be given a list of words or letters of the alphabet to recall instead. And also Digit-span tasks can be given forwards or backwards, meaning that once the sequence is presented, the participant is asked to either recall the sequence in normal or reverse order.

The video below would further help us to understand the digit span test.

What is Working memory?

Working memory is a bit more complicated because it measures how many items a person can hold in immediate memory while also doing some processing or thinking about those items. often referred to as short-term memory,

According to Baddeley (2002), working memory involves the temporary storage and manipulation of information that is assumed to be necessary for a wide range of complex cognitive activities.

For example,  a child using  their working memory as they recall the steps of a recipe while cooking a favorite meal.  working memory involves our ability to retain visually learned information momentarily while we analyze it.

Verbal working memory is involved in many everyday tasks, such as remembering a friend's telephone number while entering it into a phone and understanding long and difficult sentences.

Have you ever gone to the store without a list, thinking you’ll remember everything you need…but discovered when you got home that you forgot several items? If so, you’ve experienced the limitations of working memory.

The video below would further help us to understand the working memory.

Author's Insight:

Memory is essential to all our lives. Without a memory of the past we cannot operate in the present or think about the future. We would not be able to remember what we did yesterday, what we have done today or what we plan to do tomorrow.  Without memory we could not learn anything. I realize that working memory can help kids to hold on to information long enough to use it. And it plays an important role in concentration and in following instructions. Weak working memory skills can affect learning in many different subject areas including reading and math.