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bio-info |
| | | | | | posted 7/30/2007 17:32 |   | | | | | | | | | what i'm going to write a lot o people may think that is crazy.
Let's talk about MEMORY
Memory is the process by which a learning experience is retained over time. A single memory can be retrieved several times when the proper stimulus is presented. There is no consensus on the way in which to classify memory, but two dichotomies often arise when studied by neuroscientists. The first dichotomy is between procedural and declarative memory, and the second dichotomy is between short term memory and long term memory.
Procedural memory in humans is related to the knowledge of rules of action and procedures, which can become quite automatic with repetition. When one studies a learning curve of some task, we can see that performance is improved (either by less errors or quicker responses, or by a combination of both) with the number of repetitions of that task. Having a lot or little "practice" with certain task is procedural knowledge. Nonassociative learning and most classical conditionings produce procedural memory.
Declarative memory involves explicit information about facts. To remember one's telephone number, or the names of the parts of the neuron, does not require a set of rules or procedures, it is explicit and involves associations with other events. To put it colloquially, declarative memory is what we know consciously, and procedural memory is what we perform unconsciously. Although this dichotomy was first put forward for describing human memory, it is useful for classifying animal memory as well. A rat can improve on the performance in climbing a small ladder (procedural) and can remember if there will be food on top or not (declarative) if a light is tuned on or off.
Although this division of memory seems arbitrary at first, it is very useful in neuroscience since each type of memory probably has different types of neural substrates. For instance, the hippocampus and temporal cortex seem to be involved in the formation of declarative memory, but not of procedural memory. Whereas certain nuclei of the cerebellum and spinal chord seem to be necessary for procedural memories to form, but do not intervene in declarative memory. Due to this anatomical organization, declarative memory is said to be controlled by higher brain mechanisms, while procedural memory appears to depend on lower regions and systems.
The second recurring dichotomy in the study of memory in neuroscience, is between a short lasting stage and a long lasting stage. The short stage is called short term memory (STM) an is defined by its limited capacity and lability, since it usually only contains a few (less than seven) pieces of information, and can be disrupted easily with either strong or distracting stimuli, or with brain manipulations. If STM goes undisturbed, is only lasts from a few seconds up to several hours, depending on the type of learning and the organism involved.
Long term memory (LTM) occurs when the information is kept for longer periods, up to the whole lifetime of the organism. This occurs less often and only with association of stimuli that is relevant to the organism, either because of a biological predisposition or by continuos repetition. Usually experiences charged with a strong affective component (either reinforcing or aversive) tend to go into long term memory more often than others. This type of memory is less labile, and is not easily disrupted. The most frequent reason that some information cannot be retrieved from LTM, is a retrieval problem itself, and not that the memory is lost, since it can appear latter in another context. Very few restricted lesions have an effect on LTM, but some mayor afflictions like hypoxia (lack of oxygen in the brain), trauma or electroconvulsive shock can disturb long term memories that were stored. However, most memories come back in time, and the ones that do not were the memories most recently learned before the trauma or treatment. This lack of lability of LTM suggests that the brain (particularly neurons) go thru plastic changes that are almost permanent. In the case of STM, the changes probably involve just the way some neurons function, but not the plastic permanent changes.
On the neural level, a notable difference between the dichotomy between procedural and declarative memory, and the dichotomy between STM and LTM, is that in the latter there seems to be involved either higher and lower brain structures, and in some cases the same anatomical area is necessary for both STM and LTM. It is the neural mechanisms involved that are the difference underlying each.
Have you ever think to calculate the brain memory.
exploring the web I read this:
"The long-term hard drive of the brain is potentially an infinite amount of gigabytes.It has been found that electrical impulses can trigger memories that the subject assumed to be long forgotten. Therefore, it is believed that the brain can remember everything from birth through to death."
Sheila Kirby, Esbjerg, Denmark
I believe that the brain can't remember everything,from birth through to death.I calculate how much is the braiin memory in megabyte.I included here people between
70-80 years old.This people has a large experience of life and a large memorized events.
So, a person lives about 657000 hours,included sleeping time.
Now thinking brain as a computer,how many of us remember all moments of their life in audio and video?Crazy question, no? I think no one...
The images and audio in our memory are very poor in MB.
Some moments are totally forgeted
I calculated 1 hour of life image in about 1 MB .Then multiplicating 657000 * 1 MB = 641.6 GigaByte.
Oh we are so limited.(just in memory)
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lordjakian
[Guest] |
| | | | | | posted 7/31/2007 05:12 | | | | | | | | | | Bio-info, you wrote some fun stuff, but this piece here....
"I calculated 1 hour of life image in about 1 MB."
My question is this.
How does 1 hour of life image = 1 MB"?
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bio-info |
| | | | | | posted 7/31/2007 17:08 | | | | | | | | | | | |
lordjakian wrote @ 7/31/2007 5:12:00 AM:
Bio-info, you wrote some fun stuff, but this piece here....
"I calculated 1 hour of life image in about 1 MB."
My question is this.
How does 1 hour of life image = 1 MB"?
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When you try to remember a moment in the past of your life, do you remember all the images and words the people said to you?The images in your brain have a low quality and i think calculating in mb.
A low-quality image has a lower resolution and is composed of very few pixels. Visual, verbal, musical, or whatever-has a small size.
The analysed images of our brain in a hour has a raw size of about 1 MB. ( i'm not sure of that.i think also that 1 MB is really to much.)
Let me show now an experiment :
people were asked to read text, look at pictures, and hear words, short passages of music, sentences, and nonsense syllables. After delays ranging from minutes to days the subjects were tested to determine how much they had retained. The tests were quite sensitive--they did not merely ask "What do you remember?" but often used true/false or multiple choice questions, in which even a vague memory of the material would allow selection of the correct choice. Often, the differential abilities of a group that had been exposed to the material and another group that had not been exposed to the material were used. The difference in the scores between the two groups was used to estimate the amount actually remembered (to control for the number of correct answers an intelligent human could guess without ever having seen the material). Because experiments by many different experimenters were summarized and analyzed, the results of the analysis are fairly robust; they are insensitive to fine details or specific conditions of one or another experiment. Finally, the amount remembered was divided by the time allotted to memorization to determine the number of bits remembered per second.
The remarkable result of this work was that human beings remembered very nearly two bits per second under all the experimental conditions. Visual, verbal, musical, or whatever--two bits per second. Continued over a lifetime, this rate of memorization would produce somewhat over 10*9 bits, or a few hundred megabytes.
the experiment doesn't measure everything (did not measure, for example, the bit rate in learning to ride a bicycle, nor does his estimate even consider the size of "working memory") his estimate of memory capacity suggests that the capabilities of the human brain are more approachable than we had thought
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lordjakian
[Guest] |
| | | | | | posted 8/1/2007 00:02 | | | | | | | | | | Fun stuff, I still find it strange though.
The whole problem I see is that to give it a base number like that over a field of mediums(visual, verbal, musical, or whatever) incredibly skews the useful number that can be gained from an experiment like the one you represented.
I mean, over a lifetime, individuals do not surround themselves with what they do not connect with well. They tend to concentrate with what they are efficient with, especially those who find they are really great with one type of medium and absolutely horrible with another.
Instead of a general average, I would think the better number to find is simply the highest amount possible for a given medium which is being used by those who have a tendency towards it.
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bio-info |
| | | | | | posted 8/1/2007 00:30 | | | | | | | | | | | |
lordjakian wrote @ 8/1/2007 12:02:00 AM:
Fun stuff, I still find it strange though.
The whole problem I see is that to give it a base number like that over a field of mediums(visual, verbal, musical, or whatever) incredibly skews the useful number that can be gained from an experiment like the one you represented.
I mean, over a lifetime, individuals do not surround themselves with what they do not connect with well. They tend to concentrate with what they are efficient with, especially those who find they are really great with one type of medium and absolutely horrible with another.
Instead of a general average, I would think the better number to find is simply the highest amount possible for a given medium which is being used by those who have a tendency towards it.
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another experiment is a New Mechanism Found for Memory Storage in Brain :
Our experiences - the things we see, hear, or do - can trigger long-term changes in the strength of the connections between nerve cells in our brain, and these persistent changes are how the brain encodes information as memory. As reported in Neuron this week, Johns Hopkins researchers have discovered a new biochemical mechanism for memory storage, one that may have a connection with addictive behavior.
Previously, the long-term changes in connection were thought to only involve a fast form of electrical signaling in the brain, electrical blips lasting about one-hundredth of a second. Now, neuroscience professor David Linden, Ph.D., and his colleagues have shown another, much slower form of electrical signaling lasting about a second can also be persistently changed by experience.
They simulated natural brain activity by applying short electrical jolts to slices of rat brain and measuring the current flowing across the cells. After repeated jolting, the strength of the slow nerve signals had dramatically decreased and remained at a low intensity for 30 minutes after electrical jolts ceased.
These slow signals are produced by a nerve cell receptor called mGluR1, which has been associated with behaviors such as addiction and epilepsy. "Both of these conditions also involve long-term changes in the function of nerve connections," says Linden. "So in addition to furthering our basic understanding of memory storage, our work suggests that drugs designed to alter mGluR1 are promising candidates for the treatment of addiction, epilepsy, and diseases of memory."
What I want to say is that our brain is so closed to a computer memory.I dont think that brain memory research is so STRANGE.
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lordjakian
[Guest] |
| | | | | | posted 8/1/2007 00:55 | | | | | | | | | | "The analysed images of our brain in a hour has a raw size of about 1 MB."
"...nor does his estimate even consider the size of "working memory")
These parts also, struck me as interesting. Prhaps I'm misunderstanding what you mean :/
I'm afraid I may be lacking the perspective that allows me to see what you are talking about as being seperate from the working memory. Also, I'm not grasping how the material is measured in bits so that you can say that the brain is recreating this amount in bits with this amount of loss in quality from the original amount.
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Salil
[Guest] |
| | | | | | posted 8/17/2007 21:17 | | | | | | | | | | Guys do know a concept called 'Abstraction'? I am sure you know what it is and i know that you can apply it here. When we store images and video and audio... (Thats a very bad classification of data for something magnificent like brain.) it is actually stored in an abstracted form.
If the data was ever stored like the way it is on a computer hard disk thing would have been different. You would take hours to read an image. In the first place it would have never been possible to store an image in that way in your brain, the reason being that your brain always rejects newer neurons after a time period (which is often related to the concept of volatile memory). So if you don't make links to these newly created neurons then they are going to fall off your brain.
So what is not happening over here is sequential storage. What happens is you learn to recognize different components of an image through childhood. Following that, when you go on seeing new images you store them in your brain in a form which relates to your past experiences of seeing an image. You always store newer things in a form that realizes it's differences from the past experiences of similar things.
If a new born baby were told to remember a sentence, it won't be able to do that. The reason is not because it's brain is not biologically developed or memorization power is low, but is because the data already stored within the brain fails to abstract the new data that the baby experiences.
But an adult has enough past experiences and it helps him to easily memorize the new data through abstraction...
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tkorrovi
[Guest] |
| | | | | | posted 8/17/2007 23:57 | | | | | | | | | | Yes and from that, one may finally make the conclusion that there is no separate memory in the brain, that there is only the system, and what we call memory is only one of its properties. But i hoped that here one can assume that people already have such understanding, starting here from explaining the most simple things is a senseless effort, people who don't have that much understanding now, are not able to go further in their lifetime. So inevitably i think the only way, who wants some more advanced research, come to my forum, there we will not start from primitive understanding.
| | |  Artificial Counsciousness Forum | | |
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Spydre |
| | | | | | posted 11/29/2007 02:18 | | | | | | | | | | Anyone interested in memory and how it exhibits itself in the human brain, should take a moment and listen to the entire episode of "Radio Lab" that I've linked below. It can be heard as a live stream or downloaded as an hour long podcast.
Only one caution, for all the information that it reveals, it may leave you with even more questions than you had before you began.
Enjoy!
~S
| | | Radio Lab: Memory & Forgetting | | |
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Chad
[Guest] |
| | | | | | posted 11/30/2007 10:39 | | | | | | | | | | Question. You give a good description of the memory systems and the roles regional areas of the brain tackle different types of memory, but what physiological mechanism controls the organization of memory into regions and to specific neurons?
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tkorrovi
[Guest] |
| | | | | | posted 12/1/2007 00:11 | | | | | | | | | | Yes these brain regions is essentially all what they can talk about, and even about that they forget, that some regions may take over the functions of the other, if these are damaged or such. There is plenty of books, all about the brain, and their content is all almost the same. Someone i know, read dozens of these books, to get better and more scientific information about brain, than perhaps my project, but he didn't know considerably much more after that, and it didn't give almost anything new, to the project. But brain regions is a very old knowledge, this was known already sixty years ago.
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byt3r
[Guest] |
| | | | | | posted 12/13/2007 07:06 | | | | | | | | | | i understand your logic but i think there is a mistake in your way to compare computer memory and human's brain memory.
we know that computer memory has a lowest quant (piece or bit), and therefore it is measurable.
the problem on measuring human's memory start's here. in human's brain memory we do not have a lowest quant that represents the smallest amount of infromation that can be stored. for example: in computer memory the character "a" is represented by 8,16,32... bit. How can you say that the "a" character ocupies 1 byte in your brain? you don't even know your brain's operating system (OS) is 32 bit. or do you? let's take another example: imagine a circle. you know what a circle is. it is a curved line where every single dot it contains has the "R"-radius distance from the center O. we are able to imagine the smooth line (circle). we can zoom this circle in our imagination without loosing "image quality". we are able to imaginate a real circle and still our memory can store stuff. in computer memory the "real circle" needs an infinite amount of memory (sience this memory is quantized). i think human's memory is continuous and this "memory" is not related only to "memory neurons" but relates to the thinking process itself. i think that memories in our brain are more concentrated than you think, becouse a region of memory in computers can represent a single file but in human brain a region of memory represents for ex a girl's voice, part of her image, part of her appearance and part of someone else's appearance and maybe an infinite other thing's properties. maybe i didn't use the correct words to explain myself sience english isn't my primary language, but i'm sure u understand me. regards
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tkorrovi
[Guest] |
| | | | | | posted 12/14/2007 07:03 | | | | | | | | | | Yes it is difficult to estimate memory usage when the data is stored as a network. Everything is connected, some common parts are represented only by one link... Or, what is the amount of information of the topology of the internet?
| | | Artificial Consciousness ADS Project | | |
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Browser
[Guest] |
| | | | | | posted 1/21/2008 23:54 | | | | | | | | | | I don't think the brain has infinite memory, unless you start going into the metaphysical. Infinite memory would imply infinite physical storage, which would result in a very large head:) Brain cells grow and die so whatever capacity the brain has is in flux. Question is does closing your eyes save brain space? Ask a blind man, I doubt it.
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JohnD |
| | | | | | posted 3/14/2008 10:36 | | | | | | | | | | Considering your account of memory (pun here !) as it is describable, there is an issue here regarding inter-communication once the memory is structured.
It relates to these areas ... Logic as it applies , summation as it occurs in the use of language to describe accounting (such as in the newspaper), and finally inclusion, as it is thought to apply in the use of language.
Here is a simple piece of HP 48G code that can improve...as you would, by further involvement. But the code itself is just enough to assert the logic expressed above.
<< CLEAR
"HOW MANY THUMBS HAVE YOU GOT ?"
HALT
{ SWAP DROP } EVAL
"HOW MANY FINGERNAILS HAVE YOU GOT ?"
HALT
{ SWAP DROP } EVAL
"HOW MANY FINGERS HAVE YOU GOT ?"
HALT
{ SWAP DROP } EVAL
"HOW MANY DIGITS HAVE YOU GOT ?"
HALT
{ SWAP DROP } EVAL
-> t n f d
<< "YOU SAID YOU HAVE " t + "THUMBS and ..."
"YOU SAID YOU HAVE " n + "FINGERNAILS..."
"SO YOU HAVE " t + " THUMBNAILS"
+ "...and " n + " fingernails !"
"YOU SAID YOU HAVE " f +
"FINGERS..."
"SO YOU HAVE " d +
" DIGITS" + "...and " t +
" THUMBS !"
"YOU SAID YOU HAVE "
d + "digits..."
"SO YOU HAVE " t +
" THUMBS" + "...and " f +
" fingers !" + "...OR " t f +
" Digits ..." +
"SO YOU HAVE ... "
20 t F + - +
" TOES."
>>
>>
RPN MODE. and the LeftSHIFT key to CONT after your answer is entered.
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