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The importance of forgetting

Best we forget?

Forgetting is part of memory

Forgetting, annoying for some and devastating to others, is an integral part of how normal memory functions.

We tend to think of forgetting not as an act or process in itself but simply as what happens to our memories when they are no longer accessible. But, increasingly, forgetting is being studied and thought of as a more active process, perhaps even driven by a specific biological mechanism.

How to forget

Assuming that a neuro-degenerative condition like Alzheimer's or a head trauma isn't causing memory loss, there are a number of explanations put forward for why we forget stuff. One is natural decay as the information stored degrades over time. Our memory of a birthday party, aged seven, is not as strong now as it was forty years ago.

Neuroscientists have studied how information can leave a physical trace in the brain - actual changes in connections between neurons - and perhaps these connections wither over time if not used. One theory proposes that we forget what we've learned because new or old information interferes with it. So something we've learned is superseded by something we learn later, or perhaps conflicts with what we already know and so is discarded. Crudely, there's limited room in our heads and some things have to make room for others.

Oh, I know this one, it's on the tip of my, my …er

Forgetting also plays a part in the tip-of-the-tongue experience, when we're at a loss, usually with mouths gaping, for the right word or phrase. Psychologists have more than one theory for this phenomenon, the most plausible comes from Californian psychologist Deborah Burke, who explains tip of the tongue as a weakening of the link between the conceptual meaning of a word and the memory for how it sounds. So whilst we know what we want to say, we've temporarily forgotten how to say it.

Forgotten or just misplaced?

Often the failure to retrieve a memory reflects not "forgetting" or loss per se, but the fact that the memory was not well-stored in the first place. Alternatively, forgetting may be a temporary failure of retrieval; in this case, the memory is temporarily unavailable, but may be accessible later. However, mostly it's just that memories simply grow weaker with time; details fall away. Such forgetting is an important component of healthy memory: without some filtering mechanism, our memory would soon become overwhelmed by the details of every piece of information ever experienced, minute by minute. How would you ever remember where you left your keys?

Why does grandad keep telling the same stories?

It's believed that the older a memory is the harder it is to access, but regular rehearsal or retrieval of a memory - dusting it down and taking it for quick spin - can help prevent or delay forgetting. As a result, memories can last for a lifetime with no appreciable loss of detail. In fact people are more likely to embellish a memory the more often they recall it.

What happens when you fail to forget?

Forgetting is almost as vital as remembering. In fact without the one, we'd have even more trouble than we do with the other. Latest research suggests that some people may have an inability to forget traumatic events and this is what is partially responsible for conditions like depression and post-traumatic stress disorder (PTSD). If we're unable to let memories of terrible events fade naturally, how can we move on with our lives? Our culture of counselling has begged the question from some quarters, including British sociologist Frank Furedi, whether talking about our problems is doing more harm than good both to individuals and to society as a whole.


I am interested in the issue of "forgetting things you have to do", which happens to me a lot (and I am under 30!). Today, for example, I forgot to switch the lights off when I left the house, forgot to pick up a file I needed for work, forgot to save an email I meant to keep - the list goes on. I think Tania has a point about not storing the "task" properly in the first place. But I think I also have problems with becoming very distracted and preoccupied. I also wonder if living alone has an impact: I am accustomed to being "miles away" in my own train of thought.

janet c
I am useless at remembering numbers especially telephone nos. After 10 years of looking up my mother's phone number, I suddenly began to remember it after my husband pointed out that part of the number (8643)could be remembered as 'half' i.e. 43 is half of 86. At work, my colleagues frequently ask me questions relating to names/events/ addresses of clients who have passed through our department over the last 10 years. 85% of the time I can usually relate some fact about the person. I am known to remember many irrelevant facts, and my senior officers now ask me questions before consulting their computors/documents to save time. My husband wants to know why I can remember hymns sung when I used to attend church services almost 40 years ago,when he a regular church attender now cannot recall ones sung in past month. Is this part of having a 'butterfly mind'?

The fear of not being able to remember makes me forget. The more relaxed I am the more I can remember names and places.

I find that I have a very good memory for remembering "useless" facts and figures and a lot of other clutter, yet when I have to remember certain things that I will need I nearly always forget. I often wonder if this could be that I have a very dreamy mind and am not focusing all the time on what I am supposed to remember. As when prompted I will remember to the smallest detail. I think that this may lead onto my extreme problems with sence of direction as 99% of the time I will turn the wrong way and convince myself I am walking the right way even though deep down I know I am wrong!!!

I had fantastic memory and awareness as a school boy, always impressing adults to be able to resite bits of relavent information on subject matters that school boys wouldnt be expected to know. Now, I forget to attend important bunsiness meetings within 2 hours of staring at my schedule. I'm 28. The only way I avoid losing my wallet and keys is that I have 1 place for them that I systematically put them knowing that I would otherwise not be able to find them again. Names and events come and go but my real problem is rememebring to do things or go to meetings - I have all sorts of technological aids but they arn't reliable and don't talk to each other very well so its a pain to use. I find the best way to store a memory is to speak what I need to rememeber and when I need to remember it.

The problem i have is that i have to be constantly doing something to retain the useful information, and if i stop the information gradually goes with it. However when it come to pointless trivia it just sticks in my brain and i find, for example if i'm doing a pub quiz with my friends these seemly random answers pop out of no where and end up being correct. A strong memory i have from childhood is Elvis dying when i was 3! i can still see and hear my auntie at the time crying on the couch hysterically as she was a huge fan, yet i struggle to remember what i did a week ago. Bizarre.

I believe that much distress (and delay in recovery) has been caused to clients by the mental health profession insisting that people can't move on from trauma without reliving it and analysing during therapy. Once I took that pressure off of myself (thus ensuring that no-one else could pressure me either), the relief was immense. I can now understand that rehashing various events from my childhood was preventing me from enjoying life in the present - and that no matter how much I am made to remember or talk about, there is no answer or explanation for what happened back then. And that is normal, and I accept it.

jan (too)
Twenty something years ago I was ill for a couple of months with a viral infection similar to glandular fever and one of the effects was that I forgot how to do very ordinary things like . My neighbours did my shopping for me but one day I asked them to take me to the bank to get some cash. I walked into the bank but couldn't remember what to do. It was like being in a bank in Japan or somewhere where I did not know the system and could not read the signs. I looked around at what other people were doing and worked out that I had to fill in a cheque, when I got to the front of the queue and the bank clerk asked me for my bank card I had no idea what she meant. The strange thing is that it didn't worry or distress me that I couldn't remember how to fill in a cheque, I just felt a sort of curiosity, an "I wonder what I have to do now" type of feeling. I don't think my memory has ever been as sharp as it was before my illness. Like Ged my memory for class lists and the people I grew up with has faded.

Helen B
I would be very interested to find some information about the effect of gas poisoning on the brain and on memory.

I'm 33 and am being treated for bipolar disorder and Attention Deficit Hyperactivity Disorder (ADHD). I know that one of the side effects of my bipolar medication is "memory loss". However, I noticed that I was even more spacey and forgetful before I started being treated for these conditions. Blocks of my life seem to be missing. I cannot recall details. It causes problems with my current relationship as I try to be honest about my sexual past. I volunteer all information as I see it in my head. It appears some of my memories may be innaccurate. Friends will come over and hang out with me and my partner and joke around and give more details than they probably should about "the old me", but it conflicts with the information that I remembered and had told my partner. After the friends leave, I explain, "that may have happened that way ... I can't remember exactly ... some things they were saying did trigger some familiar memories." But we're only 7 months into our relationship. It's a big pill for anyone to swallow. It looks like I am hiding my sexual past or who I've been ... or just being sneaky, when really, I just can't remember. When I have produced stories to the best of my memory and then those memories conflict with that of a friend's memory, it only makes me look like I am lying, or only telling enough information to make myself look a great person ... and that is not the case. I don't have the most sparkly white track record, but I try to be honest. It's just hard when I can't remember that past, and want to bury it and start a new life. I finally found someone worth spending my life with. But I do believe in karma ... I realize that I am having to pay now for my past. I made bad choices in the past. Now I must faces the consequences of those choices. Has anyone had any similar experiences where their lack of memory or false memories destroyed a great relationship? Any advice? Guidance? Thanks, Tim

This apsect of my memory really does concern me a lot. Im 44, and cant even remember being in significant places like on holiday and/or significant events happening. I look blankly when my husband relates a tale of something significant that happened on some foreign holiday and i cant ever remember even visiting there never mind the event he is describing. if he wasnt looking at me with that 'she's lost the plot' again look, Id swear Id never been. Also I cant remember names - a recent example is I bumped into a guy who Ive known well at work for 5 years, and who I have a lot of respect for - i met him recently and as we were standing talking I was suddenly thinking to myself 'christ whats your name again?' and 7-8 weeks later I still cant remember even though Ive asked my brain a few times to get this for me. Im not sure its age that is the problem, I now have a mega high stress job and have to deal with masses more information and i feel this is the root of the probelm, basically my head is like one of those 'penny waterfall' amusement arcade games - if you add something new then something must drop off the edge to make space for it, never to be retrieved.I feel my brain is full to overflowing these days and that this affects my memory. I cant remember what I need to - its indiscriminate in whats lost so junk and important stuff get pushed off in equal measure.

I am interested to know if anyone has an experience of forgetting more after having an overactive thyroid. I am convinced that after problems with my thyroid, my forgetfulness became worse. it was embarrasing during board meetings at work to be asked for a comment and not be able to find the words to use. and having to search for substitutes that I could remember. of course it could be a coincidence to do with my age, I am 55

I am a student. My main task is to remember and store a lot of information every day. Last automn I had a very exhausting period - I had to do many exames. Since then I notice that my capabilities to rembember things that I study now are reduced, say to a level that doesn't seem normal anymore. Now the amount of time that I need for efficient storage of information is twice as much as before. Strange, because I never had problems in remembering since I was little. I ask myself if my brain got tired and needs a break to restore its energy? Also stress can alter the brain's memory, this is also prooven by scientists. I handle the situation by not focusing too much on this problem so that I can relax and then go back to the books more calmly. I think this helps.

Worst lapse so far (aged 40) - trying to tell my colleague that my arm hurt because I'd been lying on it in a funny way in bed - and forgetting the word for 'elbow', so that I had to describe it as 'the bendy bit in the middle of your arm' ... Totally agree with Bruce re that feeling that you know, but just not knowing ... often happens when watching TV/ films, and spending first half of film trying to remember where I've seen an actor before - at its worst the answer may not appear until several hours or days later. Most delayed reaction was remembering the word for things in red wine that make you drunk (congeners) about 3 months after the relevant conversation, suddenly while driving back from work.

Bernard T Smith
I believe that once information is "properly registered" in our memory, it is there for ever. It is indestructible. It is not possible to make the human mind forget. We cannot remove human memory as we remove computer memory, say by putting blanks over it. Like all information, once something is said and becomes memory, it cannot be unsaid. It may be modifiable; it may become out of date; it may be made inapplicable, but it can never be made not to have existed". "Forgetting" is probably caused mostly by mechanisms that work on our memory - rather than by loss of memory. Recovery from amnesia for example is like recovering from a computer hang-up. The memory is there all along. Once the mechanism is repaired, we find the memory is still there and intact. Even after the loss of a limb etc. our memory may still tell us, quite wrongly, that the limb is still there! Remembering is more than a recollection. It is not like looking up one's diary. When we remember something,we don't just recall something; we confirm it. We may say, oh yes, I do know about that; it was the day such such happened. The whole scene comes back to us with a lot of emotions attached. It may not be exacty the memory that we thought it would be. It is not as certain as computer memory would be. But, it is a verification of something. But what are our present thoughts being compared with? To whom or what are we talking when we try to sort it all out? BTS

(What happens when you fail to forget?) As part of trying therapies to help manage ME/CFS, I saw a psycho-analyist a couple of years ago and he tried going over old memories which I had found painful at the time. The idea was to 'un-block' channels which could aid my cognitive improvement. Instead of helping, I found the experience quite upsetting having to recall painful experiences I had almost laid to rest. Trying to remember what I had almost forgotten was quite stressful in more ways than one. I think it is good to forget things which you don't need to remember. The trouble is, I also seem to forget the things I do need to remember!

I'm a keen gardener but am always forgetting names of plants. However, I do remember the letter the name begins with, I seem to visualise it, and eventually the whole word comes back to me, or if not, it's relatively easy to look it up in the plant encyclopaedia.

Rebecca Atkinson
I work as a simultaneous interpreter, so my ability quickly to retrieve words is paramount. On one occasion I recall clearly, I was interpreting at a health and safety training course for a group of English speaking technicians and engineers who were going to be working on an offshore rig in Brazil. The instructor went somewhat off the script, and mentioned a lady who had come to him asking for the medical definition of "premature ejaculation". At this point, my mind went blank. Ejaculation wasn't the problem, but I couldn't find "premature". The word in Portuguese, "precose", led me to precocious; no good. So, with increasing anxiety, I started mentally flipping through all imaginable synonyms. As the second ticked by, the people in the room started glancing round, wondering what the problem was. When I finally blurted out "premature ejaculation", the relief was tremendous! Imagine if I was a man!

As a kid I did several 'rounds' in my town; bread, milk and post. As a result I knew the names and addresses of a couple of thousand households over quite a wide area. I could also recite the names of children in my school classes, recalling faces, from aged 5 to 18 until, say, my late 20s. My first job was managing a household database. Very quickly I knew the moves in and out, births marriages and deaths of several thousand households. I was unware of this capability at the time , but at 53 I realise I now longer can do it; or more accurately I no longer look at long lists or carry out the same tasks of a similar nature on a repetitive basis. Sadely even if I look at one of these lists from the past- say a class list- I don't recall most of the names. Perhaps a good example of loosing through not using.

I agree with Tania that sometimes forgetting is merely that you have failed to pay attention to processing the detail at the time, e.g. someone's name. The radio discussion failed to discuss the importance of a person's preoccupations at the time of the event, which may overide less important matters, i.e. "what am I going to say to this person". Attitude is also an important factor. As a 55 year old, I am fed up of my contemporaries using their age as an excuse for poor memory. I am sure it is because, they feel that this excuses any failure they may experience in learning new skills. When we know that learning any new skill takes a degree of effort. Children and young people forget all the time, e.g. to hand over notes from school, their PE kit etc. This is most probably due to lack of interest rather than true forgetfulness.

Stuart Bruff
Why is there no specific section on the effects of Brain damage and memory, or mention of prospective memory? Jamais vu is another phenomenon worth discussing in the context of memory.

Anne Watkinson
I undertook a course of ECT for severe depression last year, and over time discovered that I had 'lost' a whole two years of autobiographical memory, including the marriage of my two daughters, being present at the birth of my first grandchild, being taken up to London in a stretch limo for my 50th birthday and many other major events. Also important events such as 7/7 bombings etc. Up until that time I have always had a very good memory, yet now I have problems finding words, names etc, which is very annoying.

The interesting part about forgetting for me, is that it's probably the input that goes wrong. ie not concentrating enough at the time the memory is formed. Losing keys seems to be a classic example of that ... we simply don't concentrate actively on where we've put them down. Also has anyone else found it's a factor of how much stuff you have to remember all the time? Or how much you have to do at once?

I find it fascinating that the same event will trigger different memories in people. My husband will ask me if I remember so and so, I will say no I don't, and he will give me a look and an impatient shrug of the shoulders as if to say he can't understand why I can't remember co I was there. The same could be said the other way round, he does not have the same memories of the same event as me, but I understand this. I have found in life that everyone's memories are different. I often have reminiscences with my daughters and they look at me astonished, as they do not remember what I do, and vice versa.

I would like to know whether something that happens to me is a common phenomenon. I have, generally, a very good memory for numbers. I remember pincodes, phone numbers, number plates (even for my father's cars back in the fifties and sixties), postcodes, bank accounts and so on. BUT, if I read an article containing quantities or amounts, I find it very difficult to remember orders of magnitude - whether it was, for example £50 million or £500 million. it's so bad that my husband (quite rightly!) has stopped believing anything I tell him involving large numbers!

Rosina Elston
PREGNANCY When I was pregnant, I found it very difficult to remember names of new people I met. With my 4th and 5th babies, we were living in a new place, new culture, and I found I had to keep a diary to jot down the names of the people I met each day. As the pregnancy neared its close, the natural 'euphoria' induced by the cataclysmic imminence of giving birth meant that I didn't care if I forgot! However, I remember clearly the process of giving birth to each of my 5 children. They used to love me telling them their 'birth story'! I don't impose these upon them now! TRAUMA I have very poor recall of the horrific years in which I was going through a painful divorce, holding down a demanding full time teaching job (secondary)and 'bringing up' (more like refereeing) 2 young teenagers with the help of their young adult older sister. Consequently my house is full of junk I could have got rid of, but I want to hold on to those years, even if I've lost their memory. I keep meaning to sort it out so I can remember in a meaningful way. It upsets me that I have lost memories of graduation ceremonies, parents' evenings, school and college plays etc. In my head is a black hole.

Michelle Carnell
In 1987 I was a victim of a violent crime in the US, I do not remember the event, but very vividly before. I was offered Hypnotherapy but decided against it I believe that my brain has blocked it out to protect me?

What I find fascinating is when I cannot remember something (say a name of something or someone) I often know with reasonable certainty that now I've "asked" my memory to retrieve this information I will get it, though it may take a few minutes. What usually happens is that a few minutes, usually when I've seemingly "forgotten" about it, the information will suddently burst into my mind. I am often as not in mid-sentence talking to someone about something entirely different. I find it a very odd thing and it seems to be happening more the older I get (now 40).



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