By Dr Sue Jackson

This article is the first in a series focussed on short term memory problems; why we experience them and what we can do to cope. Lots of people say they struggle with their short term memory, or complain that they can’t remember “silly things”, but what does that mean? In order for you to be able to remember something, you’ve first got to pay attention and concentrate for long enough so that it can be encoded in your brain for later recall (or retrieval).

So, short term memory is made up of three key components: attention, concentration and retrieval. We’ll start by looking at these three in turn along with the common causes of problems for each which leads to the experiences that we describe as short term memory problems.

For something to get your attention it has to be important, interesting and/or meaningful to you in some way. Psychologists talk about “hot” and “cold” tasks. A “hot” task is something that you find interesting, important or meaningful, and cold task is the opposite. We naturally pay attention to things that are relevant to us (which is how come you can hear it when someone uses your name across a crowded room – assuming you don’t have a hearing problem, of course). No matter how important, interesting and/or meaningful things are to others, if we don’t find them so, we’re going to struggle to pay attention, thus inhibiting our brain’s ability to encode the information for subsequent recall. The most extreme form of lack of attention is apathy, which you might be most familiar with in the form of “voter apathy”.

Politics provides endless examples of issues which are important to politicians, but are not necessarily of any great interest to the rest of us. So, for example, do you know who your MEP is, and what they do at the European Parliament? Can you remember the details of the alternative voting systems that we had a UK referendum on? Do you know who your new police commissioner is, what their role is, and did you take part in the vote to elect him, or her? Unless you’re really interested in such things, your complete lack of interest (or apathy) at the time means that you now can’t remember the facts and details.

Attention is a key component in our dealings with other people. Humans tend to assume that what is important to them is also equally important to other people. We might want a cup of tea when we are thirsty, but the fact that the milk is running low might only be noticed (or attended to) by the person who generally has responsibility for running the house. The delegation of the task of buying more milk might prove tricky (and the source of some rows). The other person might hear the words, “Please get some milk on your way home,” but it might not register with them if at that point in time they were paying attention to getting their papers together for work.

So, when someone’s attention is already focussed on something else (e.g. a television programme), they are going to struggle to pay attention to competing information. They may even get annoyed about the interruption to whatever they are already focussed on.

Top tip: Stop what you’re doing so you can bring your full attention to whatever it is you need to be able to recall later. If you’re dealing with someone else, ask them if now’s a good time. If it’s not, ask them when would be a good time. Failing that, write it on something (post-it notes are good) and give it to them.

You not only need to be able to pay attention to something, you need to be able to concentrate long enough for your brain to do the necessary work of understanding and encoding the information for later retrieval. Allegedly, the average length of time that humans can concentrate for is 45 seconds. That’s not long! Our ability to concentrate can be affected by many factors: if you’ve got a cold, your concentration will be poorer as the symptoms of the cold (the headache, sore throat, sneezing, problems breathing, and fatigue) will keep distracting you. Similarly, if you’re in pain you’re going to struggle to concentrate.

Simple bodily functioning can cause problems to concentration. I once heard Jeremy Clarkson give a very funny description of how drivers who need the toilet are the most dangerous on the road! Their physical state significantly reduces their ability to concentrate on driving. Just being a little bit dehydrated will affect your ability to concentrate; if you’re feeling thirsty, you’re very dehydrated.

Feeling hungry has a similar effect; a gap of more than 4 hours between snacks or meals is enough to cause a significant problem in your ability to concentrate. A poor diet can lead to, among other symptoms, increased levels of confusion and significant impairment to concentration. Poor sleep and high levels of fatigue are also known to negatively impact our ability to concentrate.

Top tip: Look after yourself as well as you can, making sure you stay hydrated and eat healthy food regularly. Make sure you get enough rest and take enough physical exercise.

The final component of short term memory is the ability to retrieve (remember or recall) the information at a later date. Our ability to retrieve information is affected by all the same common problems that beset our ability to pay attention and concentrate. Additionally, retrieval is affected by other factors.

First, are you trying to use your memory for too many things? A psychologist called Miller discovered what he called “the magic number 7 plus or minus 2”. On average people taking part in his experiments could remember 7 items (or chunks) of information; but while some could remember 8 or 9, some others could only remember 5 or 6. More recent research suggests that the average is actually only 4 or 5. So, if you’re trying to remember to do lots of things, you may be overloading the capacity of your short-term memory.

Lists are a fabulous aid in terms of addressing retrieval problems, but they can be affected by what psychologists have labelled as “primacy” and “recency” effects. So, if you’re given a list of things to recall, you’re more likely to remember the first few and the last few and lose the ones in the middle. We tend to do much better if we can “chunk” or group information. So having a random list of things to do during the day is not as effective in helping your memory as if the list is sensibly ordered, either bringing similar things together, or grouping items by the time when they will be done together.

Our habits can get in the way of being able to remember things. Retrieval can be aided by appropriate social cues, but we have to recognise that we need them. The problem with habits is that they are largely unconscious actions and/or behaviour.

So, as an example, let’s say your GP gives you some pills that have to be taken last thing at night. You get them from the pharmacy and bring them home. You put them in the kitchen thinking, “I must remember to take those later.” Later on you do your usual bedtime routine: switch off the hall and lounge lights, and go upstairs to bed. In the morning, you come downstairs, look at the pills and realise that you “forgot” to take them. You might think that you have a poor memory, but the truth is simply that your habits got in the way. When you brought the pills home, you didn’t think about where they needed to be to remind you to take them at night. 

Top tip: Ask yourself 3 questions: what do I need to do? When do I need to do it? How can I remind myself to do it? Then do whatever it is you need to in order to have the cue ready to remind you. Use sensibly ordered lists.

So, short term memory is in fact made up of three different aspects, all of which are generally vulnerable to a variety of problems. It’s worth giving some thought to which aspect of your short term memory you are most struggling with. Of course, it may be that you’re struggling with all three components, but each is related to a different issue. So you struggle to pay attention to your partner’s requests to do things, you might find it hard to concentrate first thing in the morning or last thing at night (when you’re particularly tired), and you may find it difficult to remember what you wanted in the shop (having left the shopping list at home).

Of course, this article has only introduced the most common problems that affect short term memory. We have yet to address the particular issues faced by pituitary patients, or indeed some of the other vulnerabilities that can affect short term memory such as your stage of life, thyroid problems and medication side effects to mention just a few. In the next article we’ll consider the three most common causes of short term memory loss listed on the NHS Choices website:  anxiety, stress and depression.