Okay, so, getting back to some of the original intent of this blog, I'm going to toss you guys some quick science abstracts below the fold. Give me some feedback here, if you want, on what kind of stuff you want to hear about. If it were up to me, I'd mostly be posting neuroscience or cognitive psychology, as that's my field of interest.
Anyway, see you after the jump (quantum jump, that is...)
First of all, we have an abstract for a study that shows that development puts constraints on variety in evolution. Now, this article is interesting for several reasons. First of all, it is an interesting question: nature certainly seems to have an abundance of strange creatures...but the extent of this strangeness is nowhere near as large as it could be. For example, look through the creature creations of Spore players. Why aren't there things like that walking around? Also keep in mind, Spore creatures are bilateral and have a single spinal cord. So, basically, Spore players are exploring the design space of vertebrate, bilateral creatures...a much smaller subset of the total possible space. Why is it that creatures occupy only a small subset of possible design space?
This article suggests that developmental factors (basically gene regulation, all sorts of fun epigenetic factors, etc) allow for great variance between taxonomic groups, but less variance within a group - groups begin to occupy more diverse body types, but within a group, they tend to cluster. An interesting finding, overall. I'd like to know what level of taxonomic group they're talking about, so I'll probably be getting the actual paper. I suggest you do the same.
A good abstract on why some people are better at learning languages. Basically, it boils down to a correlation of being able to better discriminate sound differences. Impersonators, vocalists, etc, should be better at learning second languages, at least statistically. Of course, this is not a causal argument - some people may simply have an altered brain structure that would make them good at both. I do wonder how plastic that area of the brain is, however, and if you could train it...something to look into.
Next, we have the hypnotic induction of synaesthesia. Now, i know, I know. "Hypnosis" should set off all sorts of skeptical alarms in your head. I'd be interested to read the entire paper, though, and I'd like to see some confirmation from other lines of evidence - basically, that there is wide-range enervation between sensory modalities and that normal people merely have strong inhibition of these connections. That's about the only model I can think of that this would work for. We'll see. It's an interesting first find, and if it's confirmed by converging evidence, all the better. It actually tells us something about how the brain is hooked up.
Here's an interesting study on individual differences in memory damage as result of damage to the hippocampus. Now, in the literature, the hippocampus is thought to be key to memory formation. Damage that, and you get amnesia. For example, H.M., a famous case, had his hippocampus and adjacent parahippocampal gyrus removed to treat epileptic seizures. Well, his seizures stopped, but he also developed severe anterograde amnesia and retrograde amnesia for events about 11 years prior to the surgery. This study shows, however, that damage to the hippocampus does not necessarily lead to memory deficits. The authors admit it may be specific location and pathology - we just don't have technology sensitive enough for this, but it does put up a challenge to current neuroscience models of memory that involve the hippocampus. Look for more research in this area soon.
Finally, my favorite, the selective and safe erasure of memories in mice. Now, I read this article early this year for a class, and the abstract's just popped up on Science Daily. I find this one incredibly impressive. One of the basic take away messages is that recalling something is not like playing back a video tape - a steady-state relic of the event. Instead, recall is actually "reconsolidation" - you reconstruct an event when you remember it. This is one of the basic reasons why eye-witness testimony and memory in general is so dubious.
So, the basic paradigm is, you get a creature to "recall" an event, and then you suppress it's ability to form a memory. In this case, by the over-expression of a particular protein in the NMDA pathway. This thereby erases that memory. Now, hopefully this is memory-specific, and it seems to be, at least as far as we can tell with mice and the experiments that have been run so far.
Some people get a little antsy when you start talking about things like this..."The gub'ment's gonna come in an' take my mem'ries!" and such. Well, no...first of all, these mice were genetically engineered to be able to over-express this protein. We aren't. A drug could be developed that mimics the effects, maybe. But that's a long way down the line. Secondly, while there is certainly a potential danger in this technique, it could also be a powerful therapy tool. In fact, the "reconsolidation" idea can powerfully inform cognitive therapy already. On the other hand, the ability to erase particular memories, say, for war veterans, could be a useful tool if the patient so desires it.
Anyway, that's some of the science news that's caught my eyes in the last week or so. I'm going to try to get back on a more regular posting schedule. We'll see if it lasts.
Thursday, October 30, 2008
Taking Place Science Quickies
Tuesday, August 26, 2008
Giving Yourself to the Algorithm
My mind is going in a thousand places at once at the moment, but I feel like I should put down a little of this on paper/electronic bits.
So, as I've said before, my undergrad background is in philosophy & religion and psychology. I'm in grad school now for a masters in religious studies, but am splitting my time between that and cognitive sciences, as I'm pursuing a Ph.D. in cognitive sciences, probably cognitive psychology, but I'm looking at places where most professors are in the field of neuroscience, as that's the area I'm interested in, and cognitive psychology and neuroscience are trending towards merger anyway.
The areas I'm primarily interested in are perception and memory. These are intimately linked fields, and also tend to go hand-in-hand with issues of learning. Cognitive psychologists since Hermann Ebbinghaus have studied memory (often by rigorous self experimentation), and have come to some surprising conclusions - the spacing effect being one that interests me a great deal. Basically, this is an important combination of experimental knowledge about the learning curve and forgetting curve. This tells us something very important about how best we learn. Combined with the insights of other cognitive psychologists like Elizabeth Loftus and Robert A. Bjork, we should by now have actually implemented some of what we have learned in our methods of teaching.
Have we? Oh, hell no.
You see, cognitive psychologists, historically, have lost out. We haven't been listened to all that much. Part of the problem is that while we have excellent experimental evidence of how best to learn and retain information (remember just before you forget something), it is impractical (or at least incredibly hard) to do this outside of a laboratory setting. "Just before you forget it" sounds like a very vague statement, and is indeed difficult, at first, to quantify. Ebbinghaus paved the way, and we've refined it since then. The answer to our problem, as it has been often before, is to use computers. A complex algorithm can calculate this curve for an individual relatively easily. At that point, it is merely a problem of sticking to a regimented schedule.
Now, briefly, I want to clarify what I mean by "learning" and "knowledge". Knowledge is a thorny topic, as I'm sure The Rooster can tell you. Here, I'm going to avoid the problems of the word itself and simply refer to any facts/procedures/information that you take in. Thus, in this case, knowledge need not be "true." It is simply information which you are interested in taking in, storing, and recalling. In case you're wondering, that's basically what I mean by learning here - effectively taking in information, storing it for as long as need be, and then being able to recall it at will. Now, let us think about this...
Most people have little problem with taking in information. In the absence of learning disabilities, such as dyslexia, we have hardly any problem with taking in information like addition tables, multiplication rules, grammar rules, etc. Storing information was thought for a while to be possibly a problem...however, we know are getting increasing evidence that the actual storage capacity of the brain is not something we need to be concerned about. It is not infinite, by any means, but large enough so that we needed be concerned with it. This has largely to do with the way that the brain forms connections between neurons - something that we call long-term potentiation. Increasingly, we are seeing that there is an interaction between patterns of firing and specific neurons firing. This is incredibly over-simplified, as I don't want to get into the neuroscience of memory or recognition at this moment, and would rather stay at the more abstract psychological level.
So, our problem is really recalling information (isn't it always?) It is unlikely that once something is actually committed to long-term memory (this is a psychological short hand for a lot of complicated neurobiological activities) that we lose that storage. Instead, we lose the ability to recall the information (again, psychological shorthand. This is why in the modern day, you really have to study both to speak with any kind of knowledge about the subject, and design some very interesting studies). Now, long-term potentiation depends upon the repeated simultaneous activation of communication between neurons, so, obviously, repetition helps. We know, however, that pure repetition is not enough. Constant repetition is merely keeping the information in your working memory (this usually involves a different brain region), the way you repeat a phone number to yourself before you dial it. If anything interrupts you, for even a second, you may completely lose the number. Long-term memory is different, though teasing the two apart, and how exactly something gets from short-term memory to long-term memory is quite a complicated process. Look up the history of this type of work, it's fascinating.
So...we have been almost blasted fools in our teaching methods for years. We know that cramming doesn't work. We know that with a careful schedule, we can use the spacing effect to our benefit, but it's hard. It takes dedicated and individualized effort, but it's possible. Most teachers do not do this, because it is so impractical and hard to implement. And it takes a lot of individual effort on the part of the student. Also, there is a huge movement to say that "mere memorization" is nothing. Here's where you can take an interesting tack - memorization is learning in quite a few situations, and forms the bedrock upon which more important theories and creativity can be built. For example, you have to memorize the alphabet and a certain amount of words in your vocabulary to be able to read. If you did not, you would have to look up every letter and every word to process this post. Let's be thankful for that memorization, at least. When you memorize something in this form, it becomes almost automatic in recall. It is important to differentiate between spoken and written language in this case - different neuroanatomy comes into play. Likewise, mathematics becomes an automatic skill. The further you progress in math, and the more you use it (the same with reading), the more automatic it becomes. It is the same with just about any body of knowledge. The less you use it, the more it fades into a state that is difficult to retrieve.
For instance, I know Latin, Hebrew, a little Greek, and am learning German. I find if I take a month off from reading anything in these languages, it takes quite a while to get back into any sort of fluency. If I take a summer off, then I have to go back to remind myself of some basic grammar rules before I can read them. A year, and they seem quite impenetrable without further reflection. Wouldn't it be wonderful to just be able to recall anything at will within a few months.
Well, I think that this is slowly becoming possible. Check out this site, SuperMemo, a program created by Piotr Wozniak. Wozniak has undertaken an extreme form of self-experimentation, in the form of Ebbinghaus. And does it work? If you stick to the schedule, yes...with amazing results. Check out the May 2008 (16.05) edition of Wired Magazine for a treatment of the subject.
Wozniak has made a breakthrough of sorts - the realization that the brain operates in a way similar to computer networks (vastly more complicated, and neurons are not really like semiconductors, but they do perform some complicated integration functions and can operate like complex networks of boolean gates). By breaking down the learning process to an algorithm, and using a computerized helper, you can train yourself to learn better. By giving yourself up to the algorithm, you can take use the mechanical interactions of your brain to your advantage. This sounds mildly religious (in the John Dewey sense), and in that way, it probably is. You have to give significant time and ritual to it, if you want it to work. The problem is that this will significantly destroy your chance of ever having a "normal" social life.
This is a departure from what most people thought computer-aided learning would be. The idea was that we would use machines to store all the information that was trivial to us and free up space in our brains for real learning. The problem is - what are we using that space for now? Not much, in most people's estimation. Computers have freed up our time, but we haven't progressed much in learning, unfortunately. Wozniak wants to turn this around - use the computer to boost our own natural abilities, our own brains. Once you accept that the mind and the brain are really the same thing in basically every "conscious mind" process you want to talk about, then you can learn to use this to your advantage - all the messy, mechanical brain processes that contribute to our consciousness and learning.
It takes dedication and effort, but it is possible...if you're willing to give up on other elements of your life.
Any thoughts?
Posts
