Why are dreams so hard to remember?

Not entirely sure there’s a straight answer to this, but anyway…

On waking the other day I was able to recall, in some detail, a rather vivid dream I was experiencing just before I woke. Now, some days later, the only thing I can recall is that I had a vivid dream, with no memory of what that dream was actually about.

So, my question is twofold. Firstly, why is it that we can sometimes recall dreams quite vividly when first awoken, but that recollection fades over time? And, secondly, why are dreams so damned hard to remember generally?

My take would probably have something to do with not wanting to get dream memories muddled up with real memories (man, would that be confusing, and actually does seem to happen occasionally), but that’s as far as I would WAG.

Thanks all

I think it’s because dreams are non-linear. Random stuff happens for no logical reason and that’s quite hard to recall later on. When I wake up I will generally remember the last ‘scene’ but not much further back than that.
No doubt someone with more scientific credentials will be along soon to provide a better answer. :wink:

Maybe because dreams take place in the short-term memory portion of the brain?

That way, if you actually do remember a dream, you’re not remebering the dream itself, but rather a memory of a memory of a dream.

First of all, prove that you have “dreams”.

Ah, just kidding, my own dead horse to flog.

But to the OP: the thing I think even more interesting is that I generally can’t remember a dream of a few days ago, unless there is some real-life incident that acts as a trigger–and then the memory will come flooding back.

Say that I’m at a restaurant, and on the menu I see the special is a plate of shrimp. And holy cow, I completely forgot up to now, but now I recall that weird dream I had a few nights ago about krill . . .

Alessan: I find that intriguing, but I’m not sure I grasp fully what you’re describing. Could you elaborate on that a bit more? Oddly enough, I have used almost the exact same sentence that you just did, when talking about a dissociative experience I had once; but now I’m not sure I understand the functional application of short vs. long term memory.

One theory of dreams I learnt in college years ago, was that dreams are like the effluent of the mind - all the crap your mind wants rid of gets ejected during your sleep. If this were true, then trying to remember your dreams would be the mental equivalent of trying to scoop ones turd from the u-bend; so your mind resists.

One possibility is that you can’t remember because when you dream, your mind is in a different state than when you wake, and lays down memories that your waking mind can’t access well; like being drunk does. I recall a study some years back, where it was shown that people who memorize things when drunk remembered them poorly while sober ( no surprise ); but their memories improved when they got drunk again. The conclusion was that the memories were there, but just too distorted for the sober mind to read. Perhaps dream memories have the same problem.

Here’s a trick to help;

When you first wake up, go through the dream again in your mind. Walk through it, think about every detail that you can remember. As much as possible of the dream. Like telling yourself the story of the dream all over again. This will help you remember it.

Dreams are in the unconscious/subconscious mind, not the waking mind. So they’re not in active memory unless we work to make them so. Doing the above moves it into the realm of the conscious mind.

Most of your life is connected to day-to-day living. Most memories are things you want to remember or the unusual things that happen.

Dreams have no connection, on day-to-day reference, nothing that is ordinary to compare the extraordinary to. It’s surprising we remember them at all.

No brain expert here, but I think I think Annie-Xmas has hit upon the “mechanics” - most of what you remember is somehow based on reality: either something you did (or occurred to you) or something you intend to do. Sure, there are plenty of fabricated “visions” (be they visual or whatever) and can be thought of as “wishes” or aspirations or creative process.

But dreams are kind of random scenes/experiences that neither occurred in reality or that you would conjur to want to happen to you (at least none of my dreams). So if you think of your brain as a big harddrive, when it comes to “saving” dreams, it doesn’t make a lot of sense to - just a waste of space.
Now if you’re particularly intrigued by a dream, you can consciously remember it (as though it was a real experience). And writing down as much about the dream will help you do this. I’ve done this a couple times, and what’s amazing is that when you re-read the description even as little as a month later, you will not recognize parts that you wrote down. They will not “click” as if you really remember that being a part of the dream. Even when consciously attempting to remember the dream, I think your brain realizes it is really of less importance (than even, say, that car you happened to see on the street), and attempts to purge those memories.

A friend who was taking these “cognitive science” classes in college told me that one of the theories about memory in the brain is that you actually “store” EVERYTHING - even the most mundane, sensory inputs. Where things fall apart is your ability to retrieve the memories. I suspect that since dreams were not true sensory “input”, your brain may only “cache” (sorry to continue this geeky hard drive analogy) the memories, but they never make it to real storage.

Thank you cormac. Also, most of what we remember has a direct effect on our life. We remember the event, our reaction, and how it effected us personally.

Dreams have no lasting effect on most of us. I’ve heard of people who claim they have dreams of swimming the ocean and wake up too exhausted to go to work. But it’s rare.

Long ago, in a exercise from a Psychology class, I had a bedside journal, an a pen, and wrote down all my dreams immediately upon awakening.

I think that gave me an understanding of the reason I don’t remember my dreams, most of the time. Most of the time, my dreams are unreasoning crap. The last days events, hashed up, and and related to emotional baggage of the past or present, and falling short of logic so far as to make logic irrelevant as a comparison.

An exception does happen now and then. I actually do have really interesting, and understandable dreams, with really cool physical settings and objects. But, we are talking about seven or eight such dreams in my lifetime. I remember those just fine, and still do. I also have really memorable dreams that make no real sense, but are memorable for other aspects. A few of those I would probably just as soon forget.

I find that most of my dreams are quickly forgotten, and when I have made an effort to save those memories I have found that forgettable was entirely appropriate in describing them. Face it, most of what I think when I am awake has little to recommend it for long term retention. This does not improve simply because I am asleep.


Ok, now this is going to sound funny, but I’m sure some of you have smoked pot in your lifetimes. I only smoked for a few months then it got old and boring to me.

Anway!! What’s funny about being high is that, you’ll sometimes start thinking about something, and your imagination will run wild, and you’ll be thinking of something so cool and vivid, that it’s like you’re in a dream state. You’ll be enjoying this so much that it’s almost a state of trance you are in, then something will interrupt your thought, and you’ll completely forget about what was on your mind the last 10 minutes. Just like in a dream. When your interrupted (wake up) you forget the dream, but can remember very minor details.

Just thought I’d throw that one in…

I’ve been writing my dreams down since 1992, over one thousand dreams now, together with a diary of sorts, and I seriously doubt that popular theory.

Though I do believe that dreams are not for one purpose alone. The activity in your brain while you’re awake, has many purposes; you might try to solve a problem, you might experience a fanasy, you might remembering your childhood or planning your vacation, or whatever. You don’t “use” your conscious brain activity for one single purpose, and I’m certain - based on my experience - that dreams serve many purposes too. One of them seems to be cleaning up, but as a theory on dreams, it certainly falls short.

i’ve found that if i tell myself i’ll remember my dreams, i actually will. i’m also a lucid dreamer. like others said-- write them down before getting out of bed. there’s an old adage that says you remember your dreams until you look out the window.

I’m not sure that this is adequate to answer the question, though. Many of us might vividly remember a news or sports event that affects us only in that we saw it on TV. Why should events seen on TV be easier to remember than events “seen” in a dream?

Because you don’t remember *in dreams * or you don’t remember stuff from your real life while dreaming (ususally).

And on a somewhat related note, I had the single most vivid and amazing dreaming experience of my life when I went to sleep with some kava kava, melatonin, and ghb taken together. Brilliant and intricate visuals like you wouldn’t imagine, even feelings of physical euphoria–I’m normally NEVER aware of my body in dreams (come to think of it, I usually only dream in sight, no other sense) and a kind of sense of ‘foreverness’ that was very pleasant. And I was also the most rested I’d ever been. Sadly, I was never able to repeat that experience, and I’m still not sure what magical combination of coincidence, chemistry, and mental readiness triggered it.

O my goodness, after doing a psychology degree i have studied this over and over again.

There are two different types of sleep-R.E.M sleep(Rapid Eye Movement) and NREM (Non rapid eye movement) sleep. The first R.E.M cycle usually last for an hour and a half before a periods of NREM begins. Dreams mostly occur in REM sleep. There are 5 stages of sleep, with REM being the first and last stage and NREM being stages 2-4. The stages of sleep occur in sequence and then go backward to stage 1 and REM-sleep about 90 minutes later. This cycle recurs throughout the night with the REM period typically getting longer at each recurrence. Typically, a person will have four or five REM periods a night, ranging from 5 to 45 minutes each in duration. Around 80% of our sleep is NREM sleep. The largest proportion of dreams occur in the final REM stage. Stage 5 is a much deeper stage of sleep than stage 1.

The brain waves on an EEG in R.E.M are fast and most similar to those in our waking state, whereas those in NREM are much slower and of a higher voltage.

There are so so many theories (by Freud, Evans, Hobson & McCarley, Crick & Mitchison etc) about the function of dreaming and as to why we do and dont remember our dreams. In short, i personally believe we remember our dreams better when we wake from REM sleep than NREM sleep- it doesnt matter what the content of the dream was. However, the reason your dream fades is because of the way you encode it as a memory. If your dream was of high emotion, high relevance or was highly visual then the parts of the brain that process emotions or images or thoughts would have been activated and these then may have had more chance of being encoded as a memory. The more full the dream was (highly visual, emotional and relevant to you) the more you are likely to encode it into short term memory, think about it repeatedly after you have woken, and pass it into your long term memory.

That took several lectures in university to learn about so i have compacted it a lot, but hopefully you will get the jist. I have also probably forgotten loads or got bits wrong so i do apologise for that in advance.

Events seen on TV shouldn’t be easier to remember necessarily than events seen in a dream. It is more to do with how you encode that event as a memory and then recall upon it. Whether it is in reality or in a dream does not necessarily make any difference. If there is something, whether it is in a dream or has happened while you are awake, that you then encode as a memory and then recall upon frequently, you are then more likey to remember that than something that was seen or heard but not encoded.