How does your brain know that you know something without being able to remember it at the time? For example, knowing a word that could be used perfectly in context but not being able to remember the word. Felix Buda
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I look forward to the answers, because this is something I’ve been wondering about, too. I guess it’s something to do with the fact that the “word” isn’t the “thing”, so it’s possible for the brain to know that it has a “thing” inside it without being able to remember the “word” for it. But that’s as far as I can get, and sometimes I get the feeling that it’s not a satisfactory answer, though I can’t quite work out why. petekreff
That thingumajigery with forgetting oojamaflips is a mystery, isn’t it? If I remember rightly, they call it lethologica – and it can last a long time, too. For example, I recently found myself repeatedly trying to recall a particular word for two weeks, with no luck at all. Then one day when I was thinking about something else altogether, it suddenly floated into my consciousness. A fortnight. ThereisnoOwl
A related question might be: “Why does your brain recall the translation of a word you frustratingly can’t drag out in your native tongue?” I’m far from fluent in Spanish but when I’m struggling to remember an English word while in the UK, out pops the Spanish version. What is really odd, though, is that, when in Spain, the opposite happens. IanSouth
It’s a long time since I studied psychology but “metamemory” is the concept that covers these processes. If I remember correctly. OldFuzzface
A lexical entry (or word in the mental dictionary) is composed minimally of three parts: a phonological representation (what the word sounds like); a semantic representation (the meaning); and a representation of the grammatical category (noun, verb, and so on). All three are necessary in order for a word to be understood when heard and to be used correctly when speaking. The tip-of-the-tongue experience involves activation of the semantic and grammatical components of a word, but failure to access the phonological component. Similarly, a person may recognise a spoken form (or be able to recall and produce a form) without being able to remember what it means – an experience of “I know that’s a word but I have no idea what it means” (although the person may know whether it is a noun, verb, adjective and so on). CanadaRabbit63
Different types of memory are processed in different parts of your brain. Feelings about something, for example, are in a different area to the details of it. Familiarity is also stored in a different area. I had a brain injury and often have the “this idea/face is familiar/important and I’ve forgotten it” feeling, without having a clue what “it” was. alasdair19
As an occasional writer, I suffer this phenomenon quite often. Often enough to have created a term for it: mercury word. If you ever “‘played” with mercury in science class in school you will recall how it becomes more difficult to get hold of the more you try to hold it. I put a nonsense word into the sentence instead. For example, “Creatures that prefer to live their lives during the hours of dark are referred to as …” er, um, blast, I forgot “ … referred to as hairbrush animals” or “ … referred to as aubergine animals.” The third time is invariably the charm and the word appears in my head like a waiter when you had given up all hope of getting another drink. JayeKaye
I think you remember knowing it, and only find out that the details are missing when you try to access them. It’s a bit like a computer that sometimes has the icon for the program, in the menu, even though the software has been deleted. I had a very strange demonstration of this effect while my late partner was dying with early onset dementia (grim at the time, but thankfully now long in the past.) There was a phase when, if asked by the doctor whether she could make a sandwich, she said she could. Now at the time I knew that wasn’t correct, but for many many years previously she had indeed been an accomplished cook and clearly she remembered this fact, even though when asked to talk the doctor through the process, she had entirely forgotten the steps involved. Rejennyrated
As I’ve aged, I’ve noticed this is a more frequent occurrence. My way of explaining to others is this. A computer hard disk has both a section for storing a string of bits (call it the file), and it has a second section that records the location of that string of bits – called the file allocation table (Fat). As I get older as my Fat is getting full, and to make more room some of the Fat is rearranged, during which process there are addressing errors introduced. When I try to recall something, the Fat tells me it’s at location X but, unfortunately, that is sometimes incorrect and so it is inaccessible. It’s probably more complex but conceptually, that’s what it feels like. Monkeybiz
All information retrieval systems consist of the data store itself and an index to navigate it. Your brain, under the hood, is no different; your brain is essentially a fiendishly complex pattern-matching database. The phenomena you describe is simply your awareness of the concept/word being in your index, but the pointer in the index to where it is in the actual data store being wrong, misfiled, refiled under something else or that part of the store being temporarily inaccessible.
To make things even more flaky, your brain has no objectively structured model of information with which to build a coherent index. Instead it just builds its index from the context of when, where, how and any other parallel subjective experiences specific to the time the information was first filed (no matter how irrelevant those are to the information itself – your brain has no idea what’s relevant, nor cares). Stupidly, you’ve as much chance of remembering how to do differential calculus thinking about the pen you used at school as thinking about maths.
Hence it’s particularly hard to access memories when attempted in an unfamiliar context (such as a new place, surrounded by different people, doing a different task, or even just using a familiar word in a new syntactic context). This is why your mind goes unhelpfully blank during, say, a job interview, where literally every possible contextual cue will be unfamiliar. It’s also why memories and ideas flood back unbidden when you return to a familiar place, company, sensations etc that are enough to match and trigger the index, even if retrieves information conceptually irrelevant to whatever you’re currently doing.
Your brain often manages to find memories anyway, presumably by trying lots of partial matches and/or context substitutions in the background till eventually it throws the right bit of information into your conscious mind almost magically (usually a few minutes late).
It then adds the new, current context and sometimes the sensation itself of trying to remember the idea to its index (especially if it was a notably embarrassing social situation). This leads to the counterintuitive but familiar experience of trying to remember an idea only from the memory of when you last tried to use it.
People who seem to have good memories actually just have particularly plastic mental indexes that better handle partial contextual matches – but often at the cost of lots of throwing up flotsam and jetsam ideas, leading to difficulty focusing. Hence the stereotype of the erudite, knowledgable but ditzy academic. HaveYouFedTheFish
I remember our AI lecturer telling us how throughout history thinkers had used the technology of their time as an analogy for the workings of the mind – printing press, jaquard loom, clockwork, steam engine, etc. He opined on how futile these efforts were, but then went on – without a hint of irony – to demonstrate the analogies between computers and the mind. kneejerkreactionary
This recent Guardian article has this: “A few years ago the psychologist Robert Epstein challenged researchers at one of the world’s most prestigious research institutes to try to account for human behaviour without resorting to computational metaphors. They could not do it. The metaphor has become so pervasive, Epstein points out, that ‘there is virtually no form of discourse about intelligent human behaviour that proceeds without employing this metaphor, just as no form of discourse about intelligent human behaviour could proceed in certain eras and cultures without reference to a spirit or deity’.”
The physicist David Bohm wrote with his colleague Basil Hiley (The Undivided Universe) that people over various times have compared the brain and mind to something mechanical, then as a telephone exchange, then a computer and so on. But all this is contingent, so the better approach would be to explore the relationship of mind and matter and then be free to explore what kind of model comes up for the mind and not be dependent on analogies. Each model being a limitation, you see.
The problem with a computer idea is that such is human-made, finite in software/hardware, whereas any living thinking matter (maybe all matter/energy) is ultimately based on some ultimately unknown substrate (beyond even quarks, gluons, leptons etc). So how can we model the mind/brain on something which is a human-made idea? everchanging
The software analogy is terribly faulty. We recreate our memories constantly in the form of electrical signals and neurochemistry, and, the more often we revisit a thought or memory and the more context that surrounds it, the more travelled and stable that path is. If we neglect it, it degrades. Much of dreaming is stimulating those pathways.
When you were in high school, you remembered everyone’s name, your classes; decades later much of that is gone, but if you went to a reunion the context would stimulate those pathways. It doesn’t mean the information was stored the whole time like in a hard drive, you’re actively rebuilding pathways and “memories” as you go. Which is why it’s all so much easier to remember a word in context. Plus, in context, you are likely to be able to guess the definition as well. Thomas1178
It’s an interesting question but an imprecise one and we should be careful to not assume we know the writer’s intended meaning. There is, for example, a difference between lethologica (the “tip of the tongue” phenomenon) and anomic aphasia (a word-retrieval disorder – a description that connotes assumptions around how the brain works). In that context it’s worth first understanding what is meant by the brain “knowing” that it knows something. This is not a trivial difference. Unravelling the causes of lethologica might lead to advances in understanding how the “normal” brain works. Unravelling someone’s anomic aphasia might lead to a diagnosis of brain damage or neurodegenerative disease. Dorkalicious
We store knowledge in distributed networks. When we try to remember something, it can start to activate a node in the network, so you are aware that there is something there, as opposed to knowing that you don’t know it. If you haven’t retrieved it for a while, the connections weaken. If you give it time, the network will be slowly activated by your goal to remember it in a process called “spreading activation”. Eventually, it will hit a threshold and voilà! I find that if I don’t force it and just think of something else, the answer will often pop into my head in a few minutes. I am a cognitive psychologist who studies learning and I have been very interested in this process, including its relationship to creativity. jeanmck
After reading Thinking, Fast and Slow by Daniel Kahneman, I started playing with memory recall. According to Kahneman, the human brain has two speeds. He called the fast function System One and the slow one System Two. System Two is where complex thinking takes place. System One is very fast but superficial and does not process any serious intellectual work. System Two is a bit lazy and lets System One run the show.
When watching TV or a movie, I would regularly see an actor or actress I’d seen before but couldn’t remember their name or the show or movie I saw them in. The same would happen when listening to music and trying to remember the artist’s name. The fact that I couldn’t remember bothered me to such an extent that I would stop paying attention to whatever I was watching or listening to. When this happened one day, instead of getting obsessed with my memory’s lack of results, I said out loud “System Two, get me the answer” and continued watching/listening. Within a few minutes, the answer I was looking for just popped up in my mind! Lesunsetlesautres
First time I’ve heard anyone refer to their partner as “System Two”. Seems to work a charm though … maybe a bit of blowback at first, so I’ll keep my defences up. 44N79W
This is an example of meta-consciousness. It is arguable that many animals show signs of being conscious, but humans are the only animals who realise they are conscious, and can think what being conscious means. Other animals certainly forget things, but it is very doubtful whether they are conscious that they have forgotten anything. The question “What is consciousness?” is known as the hard problem, and it hasn’t been solved yet. Jon1306
Interesting question. I don’t know the answer but I have an equally difficult, related, question. When you finally (or immediately) dredge up the memory you are looking for, how do you know it’s the right one? It must somehow match the “hole” in your memory that allows you to know that you know. DaDooq
