Ruthanna Emrys's Journal

Would anyone be willing to beta read a 7800-word science fiction story?  Possible first contact, poly families, xenolinguistics, and dysfunctional academic politics.

I love my wife.

I got home today and saw a copy of The Watchtower on the coffee table.

Me: Oh, did we get Jehovah's Witnesses today?
S: Yes, apparently some live nearby.
Me: So, what happened?
S: They asked whether I'd noticed all the bad things happening in the world, and whether I agreed that things seemed to be getting worse all the time, and didn't I think that was a sign of the coming apocalypse?  I explained to them about the availability heuristic* and about how rates of violence are actually getting lower.
Me: I love you--what did they say?
S: That it made sense. And they stayed and rested a while before they went back out in the rain.

And now I feel like I ought to put these things together in a convenient pamphlet for the benefit of people not married to psychologists.


*I can't find a good link for this aspect of the heuristic, but in general it's easier to think of bad things that happened recently, because it's generally easier to think of things that happened recently.  And it's definitely easier to think of bad things that have happened during your lifetime.  This leads to every generation imagining a recently lost golden age when this stuff was unheard of.

"Give us a dozen healthy memories, well-formed, and... we'll guarantee to take any one at random and train it to become any type of memory we might select--hammer, screwdriver, wrench, stop sign, yield sign, Indian chief--regardless of its origin or the brain that holds it." - Elizabeth Loftus and Hunter Hoffman, 1989

H.M. is one of the most famous patient's in the history of neuropsychology. In an ill-planned attempt to cure his epilepsy, fifty years ago, surgeons cut out most of his hippocampus. Following surgery he had (almost) complete anterograde amnesia, language difficulties, and some very strange retrograde memory deficits. Any modern theory of the neurology of memory has to explain H.M.'s peculiar constellation of deficits. He died two years ago, and analysis of his behavioral data is expected to continue for many years to come.

On Tuesday, neuroscientists are going to begin the process of dissecting H.M.'s brain and creating a digital atlas of it. This will be incredibly useful, among other things settling the question of what lesions he had aside from the surgical one. (Decades worth of epilepsy, and epilepsy drugs, tend to make holes.) Everyone is perhaps a little more excited about cutting up a dead guy's brain than is entirely proper and, possibly because of this, they will be putting out live streaming video of the procedure. I will probably tune in myself. I've been running an independent study this semester, during which the student and I spent an inordinate amount of time banging our heads against the latest HM studies. We both feel much less confident in our understanding of the hippocampus than we did at the beginning of the semester. I am very much hoping that the dissection clears up some of that confusion.

The website's cheerful minute-by-minute sidebar countdown is still so wrong.

Two things showed up on my friends page today that made me think of this. The first is a brief rant from Tom at Mind Hacks on the subject of "neuroessentialism" (or "neuromysticism"), which he defines as the tendency to invoke neurological terms to support psychological claims, even when they don't actually add anything. He gives an example from Lakoff's Don't Think of An Elephant:

"One of the fundamental findings of cognitive science is that people think in terms of frames and metaphors - conceptual structures like those we have been describing. The frames are in the synapses of our brains, physically present in the form of neural circuitry. When the facts don't fit the frames, the frames are kept and the facts ignored." (When Lakoff says "frames," he means the things that I call "schemata." These are your generalized and often stereotyped representations of how the world works.)


And then Tom says:

"Indeed, for many psychological claims neuroscience can add little or nothing to our assessment of their truth. Taking for example this claim that frame-incompatible facts get rejected, knowing that frames are embedded in brain tells us nothing, but even knowing how frames are embedded in the brain may not be as useful as it first appears. Whatever neuroscientific facts we discovered about frames, the final judgement of the truth of this claim would rely on answers to questions such as is it true that frame-incompatible facts tend to get rejected? In what range of circumstances is this true and how can it be affected? The last word would be behavioural evidence, regardless of what information was provided by neuroscience."

My first reaction is wild cheering, since I'm pretty tired of hearing pronouncements that behavioral psychology is on its way to extinction, soon to be replaced by the ever-so-much-more-scientific methodology of neuroscience. But then I have to stop and consider: is this true? No question, in this case you can't ignore the need for behavioral research (which, incidentally, exists and supports at least a weak version of Lakoff's claim). No extinction for me, huzzah! But what could we add, if we knew something about the neuropsychology of the situation?

Well, the particular location in the brain of those synapses would be useful to know. Are frames--oh, smeg, let me just call them schemata--associated with sensory and attention areas, suggesting that you never even process the conflicting information in the first place? Are they encoded in your hippocampus, meaning that you can probably process the conflicting information short-term, but it will never make it into your long-term memory? Are they in your long-term storage areas, changing your memories over time to become more like your expectations? The behavioral evidence actually supports all of these claims to some degree; neuropsychological evidence might help tease out more exact processes. My suspicion is that schemata are so basic to cognitive processing that there are dozens of different ways they get represented. This would make Lakoff's description utterly useless--but it would be possible to make non-neuromystical claims, using neurological language, that would be both useful and testable.

The other thing was the latest Alzheimer's research. It seems they may finally be homing in on the proteins that actually cause the memory loss. Behavioral evidence can help us diagnose Alzheimer's (it's possible that the earliest indications may come from changes in writing style). Behavioral evidence can help us prevent Alzheimer's (the richer you keep your mental environment throughout your life, the more protection you gain--though nothing absolute). But the cure, when it comes, will be neurological.

So now it turns out that there's a community of pygmy humans living on Flores very close to the site where the hobbit skeleton was found. Is this evidence against homo floresiensis being a different species? This article says that they exist--but it doesn't give any indication that they have the same cranial oddities as the archeological specimins (i.e. the small but fully-formed brain). They're a bit taller, by about 50 cm on average, but humans have gotten taller over the last few centuries too.

Although it's not in the article, I have a hypothesis that I like. I've seen some suggestions in recent years that modern homo sapiens actually have some neanderthal DNA--that we interbred with them when we went north rather than just killing them. So maybe these relatively tall pygmies are the modern offspring of h. sapiens and h. floresiensis ancestors? Someone needs to take DNA samples in Rampasasa.

In response to a request on ozarque's journal, an attempt to dispell a couple of popular myths about brain structure.

Let's start with hemispheric organization. Pop psychologists can spend hours discoursing on right-brain/left-brain dichotomies. Ostensibly, the left hemisphere is responsible for analytical, intellectual, rational thought. The left side of your brain is staid and conservative, unemotional, and quite possibly a tool of the patriarchy. The right hemisphere, by constrast, is said to be creative, holistic, intuitive and emotional. It is probably planning the overthrow of all conventional ideas about politics and art at this very moment. Furthermore, everyone's thought processes reflect the dominance of one hemisphere over the other. In order to increase your creativity, you must practice your right-brain skills (it's assumed that most people in patriarchal American culture have ended up left-brained, or at least that there aren't any artists with a desperate yen to improve their mathematical abilities). Obviously there's an assumption here that hemispheric dominance is learned. You can be whatever you want, with enough effort. Or you can just spend all day taking internet tests that tell you if you're right-brained or left-brained.

My lovely Intro to Learning textbook (An Introduction to Theories of Learning, by B.R. Hergenhahn & Matthew H. Olson) calls this "dichotomania." It's based on a kernel of truth, but that kernel has gotten pretty buried.

Your cerebral cortex is, indeed, divided into two hemispheres. The do have functional assymmetries, the most obvious of which is that each is responsible for the opposite side of the body. The right hemisphere takes sensory input from, and sends motor output to, the left side of the body, and vice versa. This is so weird that it's been suggested that in the distant evolutionary past, vertebrate heads somehow mutated and flipped around 180 degrees. If you are strongly right- or left-handed, the motor cortex on the opposite side of your brain will be slightly more developed in the section responsible for your arm and hand.

The major difference between the right and left hemispheres is that, in most people, the left hemisphere performs most language functions. All speech production and much of comprehension originate in this hemisphere. This is where you store vocabulary, put together sentences, piece out meanings. The equivalent areas of the right hemisphere are responsible for what Ozarque refers to as non-verbal communication--particularly the "tune" of your speech. Damage this area, and you'll speak with completely flattened affect, or be unable to tell the difference between "You ate the last donut" and "You ate the last donut?!!!" Musical tunes also seem to be more a right-hemisphere thing.

For some people (about 15% of left-handers), language is in the right hemisphere instead. Another 15% of left-handers have language evenly divided across hemispheres. This doesn't appear to have any effect on your thought processes--it's only important if you go in for brain surgery.

Overall, the left hemisphere does seem to be more detail-oriented, and obviously more verbal. Processing in the right hemisphere does seem to be more holistically-oriented. However, there is no basis for the idea that people have any sort of hemispheric dominance. None. Most thought processes involve both hemispheres to some extent. Under normal circumstances, they communicate constantly, so that everything gets both broken down into details as well as perceived as a whole. You've got to be able to do both of those things in order to, for example, understand that the thing in front of you right now is a computer.

In fact, there's some evidence that creativity is a function, not of right-brain activity (where would that leave writers?), but of cooperative activity between the two hemispheres. The primary connection between the two is a wad of axons called the corpus callosum; there's been some demonstration that people who score high on tests of creativity have slightly thicker CCs. (Standardized tests of creativity: a rant for another time).

Now, certainly, some people tend to think more intuitively, some more analytically. It's the difference between someone who enjoys painting and someone who really loves computer programming or calculus. There are also people who are pretty good (or pretty bad) at both. What you like to do, or what you're good at, is a more complicated issue than which hemisphere is lording it over the other one.


The 10% myth explanation is, happily, shorter. You use all of your brain. You don't the whole thing all the time (that would be severe and probably fatal epilepsy), but everything that's in there right now has a function, and gets called on on a semi-regular basis. We know this because any connections that don't get used become weaker over time and eventually go away (we're talking about the learning and reasoning areas here--what happens to old memories is a more complicated question). This is especially notable in infants. A baby starts with an enourmous number of connections, and much of their initial learning is a matter of pruning connections that don't actually reflect the universe they find themselves in. It's like carving a statue from a block of marble, chipping away those bits of stone that aren't part of the image of a horse (or whatever you feel like carving). The only difference is that you also regularly grow new connections, as you learn things you didn't know before. The phrase "use it or lose it" is an apt one here. Skills that are used become stronger; skills that are neglected fade.

We know, roughly, what most of your brain does. That is, we can point to a section that's responsible for movement, and another that does something with language, and another that lights up when you do crossword puzzles and we're still arguing over what that means. Obviously the map is more detailed in some places than in others. However, if someone makes an argument for psychic abilities that starts with "scientists only know what 10% of your brain does--you must be doing something with the rest of it," then you probably want to look around for a better class of parapsychologist.

This started as a comment to cynthiarose's latest entry, but it got long. The original article is here, and the original report is here. The gist is that human cortex size suggests that we are capable of representing about 150 individuals as real people, and empathizing with them and trying to treat them well. Everyone else is outside of our little bubble. Of those 150, only about 12 are likely to be particularly intimate. Cyn went into the deeper philosophical and ethical implications of this, and wondered what it meant for religious beliefs like "If I hurt another person, I offend god," and "What I put out into the universe will come back to bite me in the ass." That last one is the Law of Sympathy or the Threefold Law, very roughly summarized.

Behold, as I answer a deep philosophical post with cognitive psych geekery.

Most of the numerical limits on our thinking have work-arounds. For example, we're only capable of keeping 7 (plus or minus 2) items of information in short-term memory. However, that can be 7 random letters, 7 words, 7 sentences, 7 theatre monologues...with practice, you can get some very large items in under that limit. It's called chunking, and depends on how large you can make items and still keep them meaningful to you. It's no stretch to think the same thing could be done with what I'll call Empathy Group Size.

So, the Law of Sympathy is one way of chunking your treatment of large numbers of people, and quite a rational way of dealing ethically with a large population. So is "I want to work for the betterment of poor people." So is "all politicians are idiots" (also a way of chunking, that is--not also rational). How we treat the bulk of humanity depends on whether we chunk them into units that are well-treated or poorly treated. So, "if you hurt another person, you hurt your one true god" chunks about 6 billion units into one unit--a marvel of cognitive efficiency.

Now, separately, the geek questions. I'm wondering about maximum pantheon sizes. Twelve, for intimate relationships? Or 150, for meaningful individuals? Do we have to trade off gods and people? What about pets--if you take in a cat, is that one less person you can care about, or do they go in a separate category? And is Empathy Group Size correlated with short-term memory size? (Since short-term memory size is normally correlated with IQ, that would have some interesting, if doubtful, implications.) Do we have an open slot or two into which we stick people currently in the news?

Right now, I've got a slot for "my class that meets this evening, which I still need to finish prep for." It's a motivation lecture, of course, and my third of the week.