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Traffic Jams In Your Brain
An anonymous reader writes "Carl Zimmer's latest foray into neuroscience examines why the brain can get jammed up by a simple math problem: 'Its trillions of connections let it carry out all sorts of sophisticated computations in very little time. You can scan a crowded lobby and pick out a familiar face in a fraction of a second, a task that pushes even today's best computers to their limit. Yet multiplying 357 by 289, a task that demands a puny amount of processing, leaves most of us struggling.' Some scientists think mental tasks can get stuck in bottlenecks because everything has to go through a certain neural network they call 'the router.'"
I don't think it's processing power or inability at all. I thnk it's lack of working memory. We can all work out 357 multiplied by 289 easily with pencil and paper. Very easily. And we could do it in our heads just as well if we could casually remember all the intermediary stages: e.g. 9 times 7 is 63, 9 times 50 is 450, 9 times 300 is 2,700, sum all three numbers and remember the result, now begin with 80 times... etc. But it's not easy for most people to do that. The computation is easy. But we need more registers.
Aide-toi, le Ciel t'aidera - Jeanne D'Arc.
Probably. You can scan a crowd because you have a hardware-level implementation for that; you can't multiply efficiently because that has to go through multiple levels of emulation, at least one of which has a severe lack of reliable memory.
We shouldn't forget that abstract thought is actually a very new evolutionary hack; we've only had a real culture for a 10,000 years or so. Before that, it was cave paintings for a 100,000 years. You can't expect a very experimental feature to be thoroughly optimized, yet.
Forget magic. Any technology distinguishable from divine power is insufficiently advanced.
I think it is because the brain is at heart an analog instead of digital machine. Multiplying integer numbers however isn't a task well suited for analog machines.
Uh, when I was taught math in elementary school, concepts similar to the Mayan depiction were often used. The only difference I see is that this was all done in base 10 and not in a hybrid of base-5 embedded in base-20.
I'm not really sure what you're getting at. Sure, you can represent numbers as shapes and sizes, but I don't see how this really helps mental math except when it comes to order-of-magnitude calculations.
If I want to multiply 357x289, I can already tell you that the answer is somewhere around 90000. The challenge comes if I want to know the answer to more than 1-2 significant figures. I don't see how using something like the Mayan system or any other system is going to accomplish this.
In any case, I'm not even sure what the problem that you're trying to solve is. The average person can do math well enough to get by in the real world. Sure, it would be nice to be able to walk down the aisle at the grocery store and figure out the per-unit prices in my head to 3 sig figs, but I don't see anything you're offering as accomplishing this. If I'm going to do a model simulation run I'm going to use a computer, and that requires almost zero mental effort around performing calculations - just a TON of creativity and analysis creating the mode/etc.
Here's an analogy to illustrate the category error people make when comparing the human brain to a computer:
"A Sony Walkman can record and play music in realtime, fast-forward and rewind, and store an hour's worth of music. These tasks require a 75 Mhz processor and 100 megabytes of memory on an iPod Shuffle. Therefore, a Sony Walkman has a 75 Mhz processor and 100 megabytes of memory."
2 corrections:
1. "I think it is because the brain is at heart an analog instead of digital machine. Multiplying integer numbers however isn't a task well suited for analog machines."
The humble slide rule is a beautiful analog computer whose primary job is doing multiplication. A skilled user can do multiplication with one faster than he can use a digital calculator.
2. The brain isn't a digital computer, but it isn't really "analog" either. Individual synapses are either off (not firing) or on (firing), never something in between. But the *rate* at which they fire encodes information in a way that's not analogous to either analog calculating machines or digital computers.
Comparing the human brain to *any* human technology, be it a digital computer or an analog calculator, is a massive category error.
Neurobiology is a fascinating topic. Of course a brain is not a digital. Neurons often have multiple connections (dendrites) and emit more than one type of neurochemical signal and often has more than one type of receptor. However, I can see the point that these neurochemicals are sent out in specific quanta and that a threshold needs to be exceeded to initiate a response. Thus instead of using a neuron as the basic unit but the receptor type as the unit, we can see neurology in a digital aspect. I would take it a step further that the brain would then be a series of parallel digital computers (based on receptors) that are networked to produce a series of responses, both when considering a network of neurons and within the neuron itself.
Essentially, what we are looking at is emergent behavior. On the receptor level we see digital activity. However, once we get to the neuron or brain level, the emergent behavior of the system appears analog.
We also haven't been worried so much about exact numbers of things for much of that time, and matching faces against memories isn't that exact of an example.
You're likely to recognize someone who grew a mustache or cut their hair, or to ask someone familiar to you where they got a fresh scar rather than walking right past them.
You are also not likely to care exactly how many bushels of barley you raised until you start selling the grain for currency or protecting it from known thieves. So long as your granary doesn't run out before the next harvest, you have enough grain. Even when bartering or selling for currency, unless you do a lot of it you can estimate your reserves of unsold stock. Once you move to a mercantile economy rather than being your own producer of sustenance, though, knowing how much of something you have and what you can get in exchange becomes more important.
Building things takes a similar route to economics. If you're building small houses with a central hearth, the construction skills are much more important than anything numeric. Once you're building grand temples and fortifications, engineering kicks in.
Now for the car analogy. I'll hit both engineering and economics. Once you have the materials and power sources to make automobiles and airplanes, engineering and trial-and-error still play a role. If you build custom buggies or roadsters on the weekends, you can utilize hard engineering but you probably don't need to. If you're meeting specific crash safety, fuel economy, and profit margin goals for the design of a car model and its highly automated production process for a big mass-market car manufacturer, your numbers had better be right.
Like Sleep? I can't count the number of times I've been stuck with programming logic, math word problems, etc. I'll stare at it until I can't make any more sense of it, go to bed. Wake up and within 30 seconds have the solution.
Sounds pretty close to a reboot to me.
The imperial units are usually more divisible by 3 and 4, something metrics suck at. 12 is a better base than 10 for most uses. God fscked up when he made our hand.
Table-ized A.I.