Wednesday, April 25, 2018

An Analogy Clarifying Why the "Brain Stores All Your Memories" Dogma Is Implausible

Let us imagine a man named Ed who gets a job as a warehouse worker at a warehouse called Warehouse B. Ed reports to work on the first day.

Ed: Reporting for work, sir.
Supervisor: Welcome to Warehouse B. Let me brief you on the job we need you to do.
Ed: I'm all ears.
Supervisor: We want to start storing at this warehouse all the information we get from our television set.
Ed: I see you have lots of empty shelves here. That's good; they'll be lots of storage room. So you do have a video recorder to start recording the shows?
Supervisor: Absolutely not. Such devices are forbidden here.
Ed: So how could you store all the information coming from the TV?
Supervisor: That is something you must figure out, given the rules I set.
Ed: Okay, give me the rules.
Supervisor: Nothing can be written down. We have no pens or pencils here, and you can never bring any. Writing with a pen or pencil or electronic device is forbidden here. If you want to store information, you can only use chemicals or proteins or electricity.
Ed: Chemicals or proteins or electricity?
Supervisor: Yes, we have all kinds of chemicals you can use to store the information from the TV. Plus we have lots of batteries, which you can set to any voltage you want. Plus we have lots of proteins lying around: ham, cheese, you name it. You can any use of these things to store the information from the TV set. But no writing is allowed.
Ed: How on earth could I use chemicals, electricity and proteins to store all that complicated information from the TV set?
Supervisor: I don't know. It's your job to figure that out.
Ed: Can I use some type of electronics to store the information from the TV shows?
Supervisor: No, electronics are strictly forbidden here.
Ed: I see you have lots of boxes.
Supervisor: Yes. If you figure out how to store information from the TV shows using chemicals, electricity, and proteins, you can put your successful solution in a box, and store it on the shelf.
Ed: How many of these TV shows do you need to store?
Supervisor: We need to store all the programs we get for the next 50 years. And after we've stored that, we need to be able to retrieve the information instantaneously. So if someone wants to know what was in some particular show on some particular date, we have to get that information from the shelves real fast.
Ed: So these boxes on the shelf will have to be carefully sorted and labeled, according to some system allowing rapid retrieval.
Supervisor: But you can't label the outside of any box – no writing allowed here. And once you've put a box on a shelf, you can never sort the boxes. And you can't label any of the shelves or aisles.
Ed: Wait a minute. I'm trying to imagine two years into the future, when thousands of these unmarked boxes are on the shelf. How on earth would anyone be able to instantly find a particular box when somebody asked for the info from one particular show – say, the information from the next Super Bowl or from the last episode of America's Got Talent?
Supervisor: I don't know. That's your job to figure that out. We have lots of wire – you can use as much of that as you want. But you can't bend the wire into letters. No writing allowed. And there's one other big problem.
Ed: What's that.
Supervisor: We have ten employees here who like to steal stuff. So once you start putting things on the shelves, whatever you put will get stolen real frequently.
Ed: Can you fire those employees?
Supervisor: No, they're guaranteed lifetime employees, because they're the warehouse owner's kids. They'll stay working here, no matter how much they steal. And another problem is that we get lots and lots of rats who come out every night, and who eat lots of any proteins or chemicals put on the shelves.
Ed: Can we just use some poison to kill off those rats?
Supervisor: No, that's strictly forbidden.
Ed: So let me see if I have this right. I have to set things up so that all the information that comes from the TV for the next 50 years gets stored on our shelves. But I can't use any electronics or writing to store all that information. All I can use is electricity, wire, chemicals and protein. I can use boxes, but none of the boxes can be labeled, marked or sorted. I've got to set things up so that the information from any requested TV show can be instantly retrieved, even though we'll just have shelves filled with unlabeled boxes. The information has to stay put for 50 years, even though there's ten employees who will be stealing lots of it every night, and lots of rats who will be eating up lots of chemicals or proteins I use to store the information.
Supervisor: That's about it. Can you think of some way to handle this?
Ed: Hell, no! I quit!

As you may have guessed already, Warehouse B is an analogy. Warehouse B represents the difficulty of storing information in a human brain. The stream of information from the television set represents the stream of information that flows through a particular person's senses as he lives. Storing the information from 50 years of TV shows would be about as difficult as storing the information from 50 years of living.

In our analogy, Ed is told that he must store the complicated information from the TV using only chemicals, electricity, and proteins, not by using any kind of electronics or writing. This corresponds to some limitations that would be in a brain if a brain were to store memories. We have no electronics in our brains. And neuroscientists examining brain tissue with electron microscopes have never detected any actual writing in the brain. In other words, even if we were to examine neurons at a magnification of 500,000 times, we would never see any tiny little letters that corresponded to some words in your memory.

Neuroscientists claim that the brain stores the very complex information we remember by using only chemicals, electricity and proteins. No neuroscientist has ever given a credible detailed explanation as to how such a miracle of encoding and translation could be accomplished. How, for example, could there ever be some combination of chemicals, electricity or proteins that represented your concept of your country or your religion or your mother?

In our analogy, Ed is told he must stick to a system of storage that is woefully unsuited for the instantaneous retrieval of specific information. He is told that he must put things in unmarked boxes that must be put on unlabeled shelves. Once lots of information accumulates, this system will not be able to handle instantaneous retrieval of specific information. For example, if someone asks three years from now, “What happened in the last Super Bowl?” or “Who were the winners at the Oscar awards two years ago?” no one at Warehouse B will be able to produce a quick answer. With thousands of unmarked boxes on the shelves, there will be no way to get such information instantaneously.

A brain would suffer from exactly this problem if it stored memories. For the brain has no coordinate system or position notation system by which an exact brain location could be located (such as neuron number 343,363,233), nor any labeling capability by which particular neurons or groups of neurons can be labeled. So an instantaneous recall of a specific memory (such as what a particular famous person looks like) should be impossible if it is stored in the brain. Also, neurons cannot be sorted, given the way they are arranged in a brain, with hundreds or thousands of connections between each neuron and nearby neurons. Given such an arrangement, you can no more sort things than you could sort the trees in a forest.

Suppose someone asks me, “Who was John F. Kennedy.” I instantly am able to recall an image of his face, and various facts about him, such as that he died by assassination on November 22, 1963. But how could I find that information so quickly if it was stored in some very tiny little part of my brain, perhaps from a location near neuron number 825,223,252? There would be no way for my brain to know where that exact location was.

It won't do any good for you to suggest that perhaps my brain scans all of its neurons to find that information. When you are asked some specific question, you do not at all have any type of thought experience similar to what it might be like to scan through all of your memories. You just instantly remember something. And if your brain was scanning through all its neurons to retrieve some information, that would take hours or days. You wouldn't be able to remember something instantly.

There is one other state of affairs in Warehouse B which is analogous to the situation in the brain. It is the fact that in Warehouse B there is a rapid loss of information stored on the shelves. In Warehouse B any information put on the shelves has a large chance of being lost within a few weeks, because of all the thievery by the ten guaranteed lifetime employees who are larcenous and can steal without risk, and because of all the rats that eat things on the shelves. In the brain there would be an equally great loss of any information stored, because of the rapid turnover of proteins. The most popular theory of memory storage in the brain is that memories are stored in synapses. But the proteins in synapses have an average lifetime of only a few weeks. There are other types of turnover going on. Synapses themselves have lifetimes of less than a year, as do the protrusions known as dendritic spines and synaptic boutons. As discussed here, there is no understanding of how the brain could possibly store information long enough so that you could remember things that happened decades ago. 

Just as Ed will never be able to figure out a system by which Warehouse B could actually store decades of TV shows (in a manner allowing instantaneous retrieval) given the limitations that the Supervisor has stated, our neuroscientists will never be able to specify a detailed scenario by which a brain could store memories for 50 years despite rapid protein turnover, and also allow specific memories to be instantly retrieved in the way our minds do, so that someone can name some obscure person, and you instantly recall facts about such a person you haven't thought about in many years. The most reasonable conclusion is that memories involve some mental facility other than the brain. We don't know how such a facility works, just as we don't have any reasonable idea of how a memory like a human's could possibly work using a brain.  But by postulating a non-neural basis for memory, we at least have a hypothesis that is not ruled out by what we know about the brain.

Nature never told us that a brain stores all a person's memories, and your body does nothing to suggest to you that you are retrieving memories from your brain. The idea that brains store memories is simply one that scientists gradually started assuming, without ever having sufficient evidence for such a conclusion. 

In one respect, the brain is even less suitable for storing memories than the Warehouse B described here. I described Warehouse B as having boxes and shelves, which would allow for some type of grouping effect, in which related bits of information can be grouped together. But in a brain, physical grouping should be impossible. The brain is a mass of neurons, and the average neuron is connected to 10,000 other neurons. In such a system there would seem to be no way in which related data items can be physically grouped together like pages in a manila file, nor any way in which data can be arranged in a discrete sequence, with a start point and a stop point.  As discussed here, such a system should not at all be suitable for storing long sequences, such as humans remember when they memorize songs, lists, and theatrical roles. 

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