How are memories stored and retrieved in the brain?
93771
There are three basic questions to ask about memory:\n\n    * how are memories formed?  (encoding)\n    * how are memories retained? (storage)\n    * how are memories recalled?  (retrieval)\n\nEncoding\n\n    * encoding is an active process\n    * requires selective attention to the material to be encoded\n    * one question is at what point in the process is the distracting material screened out\n          o early:  Broadbent (1958)  binaural v dichotic listening\n                + binaural (2 messages but heard with both ears)...difficult to recall\n                + dichotic (2 messages, one heard by one ear, other by other ear)...much easier to recall one message and ignore the other\n          o however, cocktail party phenomenon suggests a late filtering:  all messages are registered but only the ones with meaning are actually put into memory\n          o another possibility is that where the filter occurs depends upon the task:  the more attentional capacity that is available at any one time, the more one can use meaning and then the later input filter (selection) (Shiffrin, 1988).\n    * memories may then be affected by the amount or type of attention devoted to the task of encoding the material\n    * there may be different levels of processing which occur and that some are deeper than others, but there is no definition for what is meant by "deeper"\n          o structural encoding (emphasis on the physical structural characteristics of the stimulus) is a shallow level\n          o phonemic encoding (emphasis on the sounds of the words) is an intermediate level\n          o semantic encoding (emphasis on the meaning) is considered deep processing\n    * other aspects of encoding\n          o elaboration=associating with other information\n          o visual imagery can be used to add richness to the material to be remembered (also adds more sensory modalities)\n                + see research by Paivio\n                + then have two chances to remember something:  visual and verbal\n          o self-referent:  make the material personally relevant\n                + this requires deciding how the information is personally relevant\n\nStorage\n\n    * Over the years, analogies have been made to the new technology of the day to try to explain memory...current theories use a computer based model or information processing model\n    * the most accepted model states that there are three stages of memory storage:  sensory store, short-term store, and long-term store.\n          o sensory store retains the sensory image for only a small part of a second, just long enough to develop a perception\n          o short term memory (STM) lasts for about 20 to 30 seconds without rehearsal of the information\n                + with rehearsal short term memory will last as long as rehearsal continues\n                + short term memory is also limited in terms of the number of items it can hold (see Miller, 1956)\n                      # capacity is about 7 items\n                      # can increase capacity by "chunking" (combine similar material into units)\n                + originally short term memory was perceived as a simple rehearsal buffer but it turns out to be more complicated:  it is not limited to phonemic encoding, loss of information occurs by other means than simply decay and displacement, etc\n                + perhaps short term memory is better modeled by the CPU of a computer;  it has the ability to store a limited amount of information in its cache ram while it processes it...a sort of working memory\n          o long term memory has been suggested to be permanent:  that nothing is forgotten only the means of retrieving it is lost\n                + supporting evidence includes the existence of\n                      # flashbulb memories:  vivid recollections of important events such as the death of JFK or the Challenger Space shuttle crash\n                      # Penfield's electrical
319678
it has much to do with the formation of memories, but it also deals with emotional responses and motovation.  It does so by sending signals via the endocrine system (hormones) and the autonomic nervous system.
990603
Actually, as I understand it, a photographic memory also applies to text.  That is, you can read something once and remember it.  As to never forgetting a face, I suspect that's an exaggeration.  You probably forgot the guy who walked past you just exactly two minutes before you went into the shop where you bought your shoes the last time, didn't you?  And how about the faces in a crowd; can you honestly say you can remember every one that was visible in a picture of a football stadium full of fans?\n\nI doubt that anyone has a truly photographic memory, but there certainly are people who remember very well, and it's a very valuable asset.  However, if you don't also have a good forgettary, you can get pretty clogged up!
207902
With memory, the more things you have tied to an event, the better you will remember it.  Think of it as a computer file.  The larger your keyword list, the easier it is to search for it...right?\n\nEmotion is a powerful thing, containing motivating factors that would make the strongest man break down and cry...or the weakest woman lift a car off of her son.  When combined with the factors of an event, they are tied to that event in your memory.\nThe next time you feel sad, your brain will search for "sad," and may remember the time you broke up with sally.\nThe next time you feel scared, your brain will search for "scared," and may remember when you were all alone in the forrest.
761779
It isn't true that we only use 10% our brains.  That is a very common myth that was started because of misinterpretation of scientific data.  The fact is that only 10% of our brains is made of up actual neurons that transmit signals, while the rest are glial cells that provide structural support and nutrition to the neurons and clear waste products and excess neurotransmitters.   However, these cells are all used most of the time.\nTo answer your actual question though, the brain is sort of designed to forget things for two reasons.  There is so much going on around us that we experience, if we paid attention to and remembered everything we would be overloaded by all this information pretty quickly.  Secondly, new connections need to be made all the time to incorporate new things that we learn, so in the midst of that some other connections are weakened or lost.  Sometimes things we mean to remember are lost in this process.  Of course, our brain doesn't always work how we would like it to, but like you said generally the things that are most important are the things that we remember, which is exactly how it should be.  Why store unnecessary information?
25109
Memories are not necessarily created in isolation but rather in context.  When you were in your workshop you intended to do something but went upstairs to get something you need in the shop.  On the way you think of something else you need to do that day and the new thought dumps the old thought from short-term memory.  When you return to the shop, perhaps you see a tool you laid out or the item you planned to work on and you remember once again what you need upstairs.  This can go on and on for hours if you have a busy mind - and don't us post-its <G>.  People who never forget may have single-track minds.
51054
The brain has an unlimited measureless capacity for storage. With each new fact learned - especially in infancy & early childhood - you get a new wrinkle in your brain. No kidding! Check out brain weights of really supersmart folks like Einstein, you will be surprised! But there is no limit to what your brain can hold & it even takes in things you aren't aware of - all while running your body, as well.
394799
Try here:\n\nhttp://en.wikipedia.org/wiki/Brain
1126422
it is an innate protection mechanism, we don't really forget we just put them into a deeper level of memory, in time these memories are slightly changed until to us seems that only the good parts of it are left, and only with a big effort we can actually remember what reaklly happened.
1186522
One explanation I've heard is that the brain is storing the present into memory so quickly, we perceive it as happening in the past.\n\nThere are also the theories of parallel universe travel or having dreamt something very similar to the present.
1007609
I think this refers to a kind of memory more usually called "photographic memory" or "eidetic imagery." People who have this kind of memory can memorise a picture in all its detail and answer questions about it days later. \n\nThere is an illiterately titled site, "How good is you [sic] memory?" See there for a test of picture memory.
671217
in terms of memory capacity and storage, the human brain outperforms even a supercomputer.\n\nhowever, in terms of memory retrieval and information processing, the computer outperforms the human brain...
571192
Where is your memory? I think it means "where is your mind".
186285
Memory is linked to emotional/personal value (think about your clearest memories...usually there's intense sensory or emotional stuff going along with it). Depending on what you want the student to remember, bringing in music, dance, games such as hand clapping patterns, etc. all can help tremendously. Repetition is a big key, too, for fact recall, so drill, drill, drill!
160638
Because our short term memory can only hold very few things and only lasts 12-60 seconds...we must move things into our long term memory, which is able to store unlimited information, through repetition..this is the best way...
680498
Thats a very interesting question, and has been addressed at least to some point-It's clear, though we don't conciously remember events, that we do learn a great deal during this time, thus we "remember' a huge amount- the process of walking, controlling your limbs, facial expressions, on and on and on, are all learned and remembered event from infanthood- What we don't seem to remember are events per se- It appears as if that portion of our learning is developmentally controlled, such that the limbic system filters much of the detail out in infancy- only later, when high-level socialization occurs, does the limbic system start to recognize details and allow them to reach long-term memory. Essentially, the brain and learning are very very tightly developmentally controlled, so that certain things are learned at certain times- biologically, the brain is wired such that the most critical learning, such as how to control the body, how to interact in the most general way with people, etc, are learned first, and everything else is weeded out.  It's probably critical that this occurs, else we would remember being a baby at the expense of not learning how to walk until we were in Junior high!\nJust to address some things that were said before-we have an excellent memory as infants, and learn extremely quickly, but it is wired in a different way- There is also no evidence that events are stored at all, and thus no evidence that any of the infant memories can be "recovered" because they were not laid down to begin with.
570709
memories are stored in your MEMORY! prey you never get get Alzheimer's