February 25, 2006

Graphs for genius germs part V

Part V is now up over at GNXP -- I figured I'd get more feedback there due to larger readership. Feel free to leave comments there, as the ball's already rolling. Below are the graphs I refer to (for some reason it didn't work well when I tried incorporating both into a single post).






February 18, 2006

Genius germs: preliminary evidence, part IV

IV. Motivation from Behavior Genetics
(Part I here, II here, III here, V to follow.)

The cumulative evidence in Behavior Genetics (for pdf, see "Three Laws...") suggests ~50% of the variance w/in a population w.r.t. personality & g is left unaccounted for after considering the roles of the additive genetic effects plus the "shared environment" (SE) that is, anything that two siblings growing up in the same family share. What accounts for this leftover 50% is the "unique environment" (UE): it explains why identical twins (who share all their genes) reared together don't match each other 50% of the time. Now, that's surely a far greater concordance rate than for strangers or fraternal twins, but still, what could make up this UE that is as strong as the additive genetic effects plus SE combined?

In No Two Alike, Judith Rich Harris will present a three-piece model of personality to show how UE could make identical twins reared together look different. Razib of GNXP recently interviewed her here, and the Amazon review suggests that the heavy lifting is done by the new personality model: the systems for relationships, socialization, and status. We are thrilled to see a new personality model use "massive modularity" to make individual differences more tractable. Nevertheless, as w/ other "mind as a Swiss army knife" models (e.g., this), the more one stresses numerous components, local interactions, and complex interleaving of smaller parts, the more toys there are for microbes to subtly tinker w/ -- and the more likely it is that some bug or other has found a niche in the control panel of this most all-terrain of vehicles.

In the Behavior Genetics chapter of The Blank Slate, Steven Pinker devotes two pages (p. 396-7) to the role of chance in neural development: e.g., "...a neurotransmitter zigs instead of zags, the growth cone of an axon goes left instead of right..." But just what causes these chance events? The presence of microbes adds more possibilities for molecules to ping off of one another, though the process appears to use feedback loops to keep such events from snowballing into destruction. And what about the growth of axons? (An axon is the long fiber that caries the electrical impulse from the nerve cell body.) A puzzle in neuroscience is how neurons wire themselves up -- the growth cone of an axon is like a set of fingers that chemically feel their way through the environment in order to guide growth. That is, they can either be attracted to or repelled by chemical cues, but how they do this is largely unknown. If microbes were adapted to mimic such cues, they could guide axons in ways that benefited the host (as some gut flora digest the undigestible) or in ways that harmed the host (as some gut flora cause ulcers). More, the microbes might not be designed to do so, but perhaps their waste products after digestion mimic such cues, indirectly altering the neural wiring diagram. We do not propose these possibilities as an alternative to higher-level causes like Harris' but as a more strongly biological supplement in accounting for UE.

How could this alter personality or g, though? In example 1ii) in part III, we mentioned how it might affect g, so we now outline a subtle personality tweak: being a cat-lover. In my experience, cat-lovers seem to share some Big Five traits: the expected values for Introversion and Neuroticism would be somewhat above the population mean. Now, part of this could be that individuals who have a certain personality profile (for reasons having nothing to do w/ brain germs) seek out a pet most agreeable to their profile. But might the causal arrow also go the other way around? Could a brain germ compel you to seek out a certain pet, entailing subtle personality changes in the pursuit & maintenance of said pet?

Here's how it would work. The germ would make a copy of an existing (innate) cognitive algorithm for responding to and treating human infants -- e.g., {if GOAL = raise infant, then RUN 1, 2, 3...}; among these latter sub-routines would be things like {if input to visual system = search image (infant's face), then RUN happiness; RUN x, y, z... to acquire real-world correlate of search image (mate); treat infant in ways a, b, c...} The germ would then alter one symbol w/in that program, namely "infant" to "cat." Because there are two copies of the program, the affected person would seek out both -- relative priority to be determined in each case, though likely the cat takes lower priority. However, a more parasitic strain of the germ might alter the "infant" symbol to "cat" w/o making a copy -- the person would feel compelled to rear not infants but cats. (The reader has likely met both sorts of cat-lovers.) To best carry out these programs, personality must be subtly tweaked so that it agrees w/ average cat "personality," lest the host be turned off by their target "child's" solitary nature, for example.

But is there empirical support for such a hypothesis? In humans, not yet, but there is an clear parallel in rats: toxoplasma gondii. A rat becomes infected, say, from protozoa shed in cat feces. The protozoa enters the rat's brain & somehow dials down or switches off the rat's instinctual fear of the smell of cat urine, making it more likely to wonder near its natural predator and be killed. The protozoa then enters the cat, reproduces w/o apparently altering the cat's behavior (somewhat like falciparum malaria in the mosquito), and is shed in the feces, where it is then picked up by another rat, beginning the cycle anew. As for humans, we are a cat's natural caretakers, not prey, so a different strain of t. gondii could tweak our behavior to exaggerate our role accordingly. Say a human infant picks it up from indoor cats, the bug wires the human brain to cause cat-nurturing behavior, which throughout the human's life will bring the bug into contact w/ numerous other cats to infect, in whom it will reproduce & be shed, infecting some other infant, beginning the cycle anew.

Note that the longer the period between initial infection and reaching the microbe's ultimate goal, the more the selection pressure is for gentleness, lest it prematurely crash its hijacked vehicle. This parallels the case of the least harmful strain of HIV, which is passed from mother to child -- if the virus were too virulent, it would kill its vehicle before reaching its next host. Conversely, brain germs that are spread by unaffected vectors, contaminated water, or many-partner casual sex would undergo selection for increased virulence (presumably the nasty mental illnesses, e.g. tertiary syphillis). Paul Ewald develops this point in Plague Time.

We conclude w/ how microbes could partially account for regression to the mean -- i.e., the tendency for a child's value on some quantitative trait to be closer to the population mean than the values of the parents. The expected value of the child's trait is the parents' value (all expressed as z-scores) multiplied by the narrow-sense heritability (h^2), which in most cases is less than 1 and greater than or equal to 0. For example, if both parents are 1 SD above the mean in IQ, and h^2 = 0.4, then we expect the child to be only 0.4 * 1 = 0.4 SD above the mean. Similarly, if the parents were 1 SD below the mean, we expect the child to be only 0.4 SD below the mean. In whites, those numbers would be 115 for the above-avg parents, 85 for the below-avg parents, 106 for the above-avg child, and 94 for the below-avg child.

However, sometimes the actual value of the child is farther away from the mean than the expected value. In part this could be simply due to genetic noise occasionally foiling our expectations. But if microbes affect the brain during the long childhood of humans, this too could foil our expectations -- say, the child of below-avg IQ parents became even more below-avg than expected because he was infected w/ a germ that hogged the brain's energy resources. Or say a child of above-avg IQ parents is even more above-avg than expected because he was infected w/ a germ that helped cognition the way some gut flora help digestion. Perhaps it might help to think of a shorter time-frame. Exams are often used to illustrate regression to the mean: if a student gets an 85 on a mid-term where the mean was 70, we expect him to score closer to 70 on the final since some of his initial high-score might have been due to luck. But suppose he becomes infected w/ a germ that chemically mimics the effects of caffeine, which increases awareness & fights fatigue, allowing him to score in the 90s on the final. The same principle may operate over longer time-frames.

This discussion seems to have a heads-I-win / tails-you-lose quality to it: namely, that microbes could be invoked to partially account for any aspect of human (or animal) behavior. But then, in this respect microbes are no different from genes or "cultural differences." Moreover, in general genes do not harm the organism housing them in order to benefit themselves, one reason that motivated Ewald & Cochran's "new germ theory" of fitness-reducing traits (click 1st item of this search). But microbes are alive and rapidly evolving, meaning they can be invoked to account for either fitness-reducing or fitness-increasing traits in the host, depending on whether the bugs are mutualist or parasitic. Only empirical investigation can answer questions posed by hypotheses, but the hypotheses themselves should be as imaginative as possible, lest we leave an area of the truth unexplored. In part V, we will at last provide fairly solid (and to our knowledge, novel) empirical support that microbes do impact human cognition at the genius level.

February 17, 2006

Genius germs: preliminary evidence, part III

III. Subtle brain germs
(Part I here, II here, IV, V to follow.)

In Part I, we mentioned 3 brain diseases where the pathogen crosses the Blood-Brain Barrier (BBB): African sleeping sickness, progressive multifocal leukoencephalopathy (PML), and bacterial meningitis. There are of course more -- polio goes from the gut to the nervous system about 1 per 100 cases. We now lay out scenarios whereby microbes affect the human brain. For simplicity, we assume that even subtle tweaking of the brain is never completely neutral to the host w.r.t. reproductive fitness, so it's + or -, w/ the magnitude to be determined case by case. We conceive of at least 4 routes for microbial influence: 1) direct, 2) indirect, 3) by chain, & 4) by inter-species cooperation -- each of which can be + or -, making 8 scenarios. While most of the cells in this matrix are unexplored, we present them to show the many ways microbes could affect the brain.

1i) Direct, Minus: The microbe makes a bee-line to its niche in the brain and exploits the brain for its own fitness. Examples: sleeping sickness, PML, bacterial meningitis, rabies; being a cat-lover (? -- admittedly small magnitude, and I say this as a cat-lover).

1ii) Direct, Plus: The microbe high-tails it to its neural niche, where it aids in cognition in order to derive some fitness benefit. Examples: unknown. But consider a microbe that chemically mimicked the effects of a neurotransmitter to increase the signal to noise ratio in neural transmission. See here for evidence that higher IQ correlates w/ lower glucose metabolization rate -- i.e., the brain expends less energy in smarter people. If a microbe helped this happen, it could, e.g., digest some of the glucose saved due to efficiency gains.

2i) Indirect, Minus: The microbe is adapted to a niche elsewhere, such as the gut or respiratory tract, but by chance one gets into the bloodstream and then into the nervous system, where it harms the host while not benefiting itself. Examples: polio; male homosexual germ (?).

2ii) Indirect, Plus: Again, a bug adapted to the gut or respiratory tract wanders into the bloodstream & crosses the BBB. Examples: unknown, though this is the category we ascribe to the "genius germs" we will posit in part V to account for very lopsided seasonality among genius births. Suppose the effect is to increase the radius R of the "spotlight" of attention that we mentioned in part II. Now the person can mentally juggle more items, boosting IQ and increasing fitness. See here (Ctrl F longevity) for evidence that higher IQ correlates w/ better health (duh). Since the bug is not specialized to thrive in the brain, it would not survive long, but a neural tweak at an opportune moment in early development could have a lasting effect.

3i) By chain, Minus: "Chain" here refers to a chain of command as opposed to an individual bug, something like an eusocial colony of microbes. Say the headquarters is in the gut but that a caste of soldiers enters the bloodstream & crosses the BBB. There, they either loot the brain for food to bring back to the hive, or they tweak the brain center for hunger to compel the host to eat more than is healthy (in any human society, hunter-gatherer or otherwise), so that more food ends up in the gut for the hive to feed on. Hunger is associated w/ the hypothalamus, a part of the brain that is easier to infect since it does not have a BBB. Examples: unknown; obesity germs (?).

3ii) By chain, Plus: Same route as 3i), though the effect would be like that of 1ii), where some of the resources saved due to efficiency gains are distributed among the hive. Examples: unknown.

4i) Inter-species cooperation, Minus: Same as 3i), though instead of specialized castes within a species, several species maximize their competitive advantage and cooperate, w/ the same effect as in 3i). Why wouldn't the species that crossed the BBB just keep all the food to themselves? Perhaps the species adapted to the gut protects them from other microbes that would otherwise wipe out the brain-adapted species. Examples: unknown; obesity germs (?).

4ii) Inter-species cooperation, Plus: Same as 3ii) but w/ the teamwork described in 4i). Examples: unknown; though boosts in IQ could require several species working in concert.

Most of the categories with unknown examples involve a benefit to the host, which probably reflects the greater likelihood of a microbe harming the host rather than helping it, as well as the innate cognitive bias of disgust -- microbes could not possibly aid cognition because they're icky, icky germs. But they must be doing something -- remember, in the gut alone there are 10^13 microbes. Let's say only one millionth of them are even capable of passing into the bloodstream and then past the BBB, and that of these potential brain germs only one percent actually does so (in only 1 per 100 cases of polio does it affect the nervous system). That still leaves 10^5 microbes, though suppose for whatever other reasons the number is cut down to 100 microbes -- they're in your body from birth. The downside to our sophisticated brains is that they take a long time to develop, leaving at least a decade for these microbes to wander in and tinker w/ this or that value for one mental module or other. So again, the likelihood that all of these microbes acting over all of this time have no effect on cognition or personality is nihil.

February 14, 2006

Genius germs: preliminary evidence, part II

II. Measuring creativity and genius
(Part I here, III & IV to follow.)

Before Part III discusses how germs could contribute to genius, we must define "genius" and build a model for "creativity." Informally, a "genius" has smarts, "thinks outside the box," and shows Herculean output. So, we would look for them among revolutionary figures in the arts & sciences. We formally define a "genius" as someone who shows up in the upper 5 "deciles" by Index Score in comprehensive rankings of eminence. The bible of such rankings is Charles Murray's Human Accomplishment, to which we refer. He consulted many encyclopedias of the arts & sciences, determined who was mentioned most and given most space across all volumes, and rank-ordered the figures by raw score, w/ the raw score of the top figure set to 100 (e.g., Michelangelo in Western Art). Several top 20s are here. "Decile" here is not frequency-based but refers to Index Score. So for Western Music (see previous link), Mozart and Beethoven have an Index Score at least 90, so they are in the 9th decile; Bach and Wagner are in the 8th; etc. Murray began at 800 BC and ended at 1950, covering the entire globe for the sciences, while creating separate categories for the arts (e.g., Western Lit and Japanese Lit).

The rankings do not reflect mere fashion because the plots of how many figures are in the 1st through 9th deciles model a hyperbolic curve (one that approaches its asymptote much faster than a bell curve), just as happens in the clear case of rankings of excellence in sports -- Murray (p. 101) shows a similar curve for percentage of golfers who have won varying numbers of victories in the Majors in golf. That is, of those who showed up at all, most won 1 to 3 Majors, after which the curve levels off; almost no one won 5 - 18 Majors. Since victory in the Majors reflects overall excellence rather than fashion or speciality in one narrow aspect of golf (such as driving), curves which resemble it in the arts & sciences can be assumed to reflect overall excellence as well.

Murray stopped at 1950 to dampen "epochcentric bias" -- the tendency to overemphasize the importance of the recent past. The most recent figures' scores could reflect such bias to some degree, but since few of them show up in the upper 5 deciles anyway, this will not impact our discussion of genius. Disclaimers: 1) Before dismissing Murray's approach based on my whirlwind summary, read the book first (which is accessible; reviews here, here, and here). 2) We can agree that Mozart was a more aesthetically excellent composer than Bizet (Index Scores 100 vs 10, respectively), even if one finds Bizet more agreeable to one's tastes.

So what makes a genius mind? Dean Simonton is the authority on psychologically modeling genius, and to recapitulate, a genius is one w/ exceptional intelligence (psychometric g), "outside the box" creativity, and an untiring work ethic. As for work ethic, we interpret this as a high score on the Conscientiousness factor of Big Five personality tests. But hard-working though geniuses are, we assume the primary factor in accounting for genius isn't Conscientiousness but the combination of smarts plus creativity. Ah, but that raises (not begs) the question: is "creativity" independent of "intelligence" like "athleticism" is? John Carroll's Human Cognitive Abilities, a massive summary of psychometrics, including tests of g and creativity, shows that as yet there is no evidence that creativity is independent of g -- in fact, the available data suggest that the two are highly intertwined, and since g is the primary factor on all mental tests, our default assumption is that "creativity" is really just another "flavor of g." Carroll (p. 428):

It appears to require a considerable degree of general cognitive ability [i.e., g] for an individual to be able to make high-scored responses to tests of factor FO [i.e., "originality" or "creativity" factor]. . . .[T]hese data provide no evidence for or against the hypothesis that there is a threshold of intelligence above which there is little relationship between intelligence and creativity. . .

Here is a visual of his meta-analysis: one general factor at the apex (General), a handful of broad "flavors of g" like auditory (Broad), along w/ myriad specific abilities such as pitch perception (Narrow). So, we assume that what we call "creativity" is either a Broad ability or is distributed among Broad and Narrow abilities. Recently, Linda Gottfredson dissected claims by Robert Sternberg that "practical intelligence" (something like common sense) was a cognitive ability largely independent of g (for pdf, Ctrl F dissecting). She found that there was no evidence that it was independent (most of the samples Sternberg examined were biased toward high IQ, rather than examining the general population), and plenty of evidence that common sense is largely explained by g. Absent compelling contrary evidence, we assume the same holds for creativity's purported independence of g. As an aside, we introduce our own term for "flavor of g," which gets more to the point: we call Carroll's Broad & Narrow abilities "shadows of g," meant to suggest both the various shapes the single g factor casts, as well as the analogy to Platonic Forms and their myriad Particular instances.

Now, as a former IQ skeptic, I must reassure those I've upset w/ the suggestion that the ineffable quality "creativity" is a mere shadow of g, which many (falsely) mistake for nitty-gritty analysis. We start w/ two run-of-the-mill IQ question types that require "outside the box" thinking, and then we formalize the creative thought process. First the questions (answers & remarks at the bottom of the post). Consider the following sequence of numbers, and then fill in the blank w/ the next number:

23, 57, 1113, 1719, 2329, ____ ?

Now, consider the sequence of pictures here, then choose the next picture.

Both require unusual thinking (as explained below), and the picture sequence is the type tested on Ravens Progressive Matrices, the most highly g-loaded IQ test. Therefore, we see no problem w/ viewing creativity as a shadow of g. A question type frequently tested on creativity tests asks the person to devise a novel use for an existing tool, say a cup. Again, this sort of "What if I tried this?" thinking is what's needed to solve a brainteasing Ravens problem.

To formalize creativity, we begin w/ Dean Simonton's model of creativity as a metaphorical Darwinian process. (I read his work after thinking about this topic, so I was disappointed to find that I'd been scooped on the rough outline of the model. I suppose I can console myself w/ "Great minds think alike!") For overviews, browse his publication list (for pdf, Ctrl F 195), or read Origins of Genius: Darwinian Perspectives on Creativity here. Essentially, he believes geniuses are capable of unconsciously generating greater quantity & remoteness of variations on an underlying idea, among which they consciously select the "fittest" -- the one likely to bear the most artistic or scientific fruit. The underlying idea is like the initial genotype, the variations are blind like random mutations producing novel genotypes, and the artist's choice plays the role of natural selection. He has the generation of random variations doing most of the work; the idea is that geniuses are better at this stage of the process than the rest of us.

However, coming from a linguistics background, I find the mental generation of random variations simple. To mention just two models, Optimality Theory (OT) in phonology tries to model how the sound of a word that's stored in our mental dictionary surfaces when it's pronounced from our mouths. Take the plural word "dogs." Simplifying notation, this could be pronounced with an "s" sound or a "z" sound at the end; in reality, it has a "z" sound. The mental dictionary form is the genotype which is fed to a function (called GEN) which returns the infinite set of variations on that form -- e.g., "dogs," "dogz," "digs," "bladiblabla," ad infinitum. This infinite "candidate set" is then fed to another function (called EVAL) which processes (at the unconscious level) each member in parallel and marks each member that violates certain rank-ordered constraints (which are like selection pressures). The candidate that incurs the fewest violations of higher-ranked constraints is chosen as the "fittest" form. In our example, "dog-z" wins because the "g" and "z" sounds agree w/ each other on the value of voicing (whether or not your vocal chords vibrate), a highly ranked constraint in English, whereas the "g" and "s" sound don't agree in "dog-s."

Though OT and natural selection are isomorphic in many ways, the metaphor should not be taken too far, as pronounced forms do not breed and spread throughout the population. The key point is that the infinite set of blind variations is easy to get: just supply a form to the GEN function, and it'll mutate each constituent sound in every imaginable way, as well as add or delete sounds. The heavy lifting is done by the EVAL (or selection) function; it must simultaneously juggle all candidates and check the constraint ranking to see which is the most fit.

Second, a standard model for the semantics of questions is that the meaning of a question is simply the (in principle, infinite) set of possible answers; the job of the responder is to single out the answer from that set. For the curious, see the right-hand side of page 4 in this handout (pdf) by Paul Hagstrom. So, "What is the President's name?" means the infinite set of possible names; the responder then picks out the correct name from the list. Again, the key point is that generating an infinite set of blind variations is easy -- simply replace "What is the President's name?" with the infinite set of sentences "The President's name is x" for all names x. The heavy lifting is done by the responder who searches the list and singles out the answer.

We now apply these theoretical approaches to modeling creativity. (Note: for the empirical support for such a model, read Simonton's work. We present here what we view as an improvement on Simonton's cognitive model.) We view the creative "problem" as identical to a question, e.g., "What shall I paint?" This problem is fed into a function we'll call GEN, which returns the infinite set of answers -- but because not all answers are satisfactory solutions, this set is best visualized as the "idea landscape," on analogy w/ the fitness landscape concept in evolutionary biology, where peaks & valleys represent fitness maxima and minima, respectively. In reality, an answer to "what to paint" likely has many more dimensions than two plus a fitness indicator, but for ease of presentation, we treat them as ordered pairs plus a fitness indicator. An algorithm we'll call INIT ("initial") takes in this landscape and returns a randomly chosen finite cluster of starting points to investigate. These starting points are then fed into a hill climbing algorithm called PON ("pondering"), which in parallel maps each point to a higher adjacent point until it reaches a local maximum. These local maxima represent the conceptual statues hewn from the conceptual marble. The finished product results after, e.g., putting pen to paper to flesh out these outlines -- which in turn may illuminate other starting points to investigate -- and choose the best result.

So what separates these processes run by a genius mind from those run by an ordinary mind? A naive first guess might be that the INIT and PON algorithms are simply run continuously, so that geniuses have more random starting points to investigate, increasing the odds that one of them will be worthwhile. But this would imply that geniuses merely think longer about a problem. Moreover, unlike the EVAL function in OT, the PON selection algorithm is a largely conscious process and is thus subject to constraints on attention and number of items being mentally juggled at once. We therefore introduce the following to restrict how INIT chooses its cluster of starting points for PON to make climb hills -- the idea is that the cluster is a "spotlight" of attention defined by a center C and radius R (roughly, "focus" and "scope," respectively). By hypothesis, natural selection has hard-wired the default search locations for these to correspond to "obvious" solutions; for example, in the problem of "Who shall I mate with?" the C for males is wired to focus on the female region of the landscape, with R set to a small radius (lest he consider males as well).

Veering from the default settings is not inconceivable, so we posit Flexibility Constants for the C and the R (FC-C and FC-R). A low value for an FC indicates low tolerance for deviation from the default, and similarly for a high value. We propose a simple method to quantify them: namely, as the expected value of fitness loss due to allowed deviation from the "obvious" solution (expressed as a percent, thus from 0 - 100). So for the mating problem in male brains, if the C were flexible enough to focus on the male terrain rather than the female (it could still survey it, but would not bother generating starting points there), then the FC-C would be 80 for this problem, since gay men have on average 80% fewer kids than straights. By contrast, pursuing the "obvious" solution would entail an FC-C of 0, since by following the cumulative wisdom endowed by natural selection, one doesn't expect to have fewer kids. Thus, the FC-C and FC-R are 0 for adaptive problems in normal individuals, e.g. "who to mate with" or "what to eat."

Consequently, for fitness-neutral problems, e.g. "what to paint," the FCs may well describe a bell curve centered around, say, 50 rather than be so lopsidedly biased toward 0. The variance in FC-C (again, how tolerant one is to focus on unusual regions) we interpret as the variance in g and perhaps the Openness factor in the Big Five personality model. See here (pdf) for evidence that at least among college students, g correlates +0.43 w/ Objective Openness (openness to ideas, actions, and values, not fantasy, aesthetics, or feelings). The variance in FC-R (again, how wide the scope of consideration is, or how many starting points are being mentally juggled) we interpret as the variance in Digit Span measured on, e.g., the Wechsler IQ test. So, geniuses are expected to have remarkable values for FC-C and FC-R in fitness-neutral problems: tentatively, 3 SD above the median of practicing artists & scientists.

As with other aspects of personality & intelligence, variance here is due to a combination of genes and environment -- such as germs affecting the brain. In Part III, we will briefly examine how germs could affect cognitive ability in ways less obvious than, e.g., aggression caused by rabies.

Answers: The next number is 3137. Each term is a pair of consecutive prime numbers. Thus, the person must shed inhibitions that there is an arithmetic operation between each term (say, adding or multiplying), as well as the inhibition that the numbers are atomic rather than glued together.

The next picture is B. Each color moves one ring outward until it reaches the outer ring, at which point it loops back to the center. This requires seeing a ripple-like movement among three "snapshots." One must also shed the inhibition that the ripple must continue in the direction it started, like a real ripple, rather than be caught in a loop.

February 11, 2006

Genius germs: preliminary evidence, part I

I. Background
(Parts II, III, & IV to follow, will focus respectively on definining genius / creativity, how a germ could contribute to genius, and evidence for genius germs by examining winter-spring seasonality of births of the giants among giants in scientific & artistic fields.)

Of all the imaginable sources of variation in higher cognitive functioning among human beings, the one that remains the least explored is the role of microorganisms. Consider the gut flora: in the gut alone there are 10 times as many microbes as there are cells in the human body (10^12 human cells * 10 = 10^13 gut microbes), which represent some 100s of species. Some of them are parasitic: indeed, the 2005 Nobel Prize in Physiology or Medicine was awarded to Barry Marshall & Robin Warren, two Australian doctors who proved that the helicobacter pylori bacterium causes much of gastritis and stomach ulcers, despite conventional medical wisdom that they were due to genetic profile and/or diet & lifestyle, a vindication of Paul Ewald & Gregory Cochran's new germ theory (click first item of this for the pdf). Of course, gut flora also contain species that benefit us, not out of sheer kindness, since the stuff we can't digest is food for them. Because we have no clue what most species in the gut are doing, only further research can resolve the ratio of parasitic to mutualist bugs.

So they're in our colon -- are they in our brain, too? If you took a neuroscience class or read a few popular articles on it, you might remember that we have what's called the Blood-Brain Barrier (BBB), a very narrow passage from the bloodstream to the nervous system which protects the brain by only allowing in a tiny range of molecules, like a sieve, unlike the more open passages to other organs. However, most neuroscientists lack a true appreciation for the role of evolution, for once we observe a neurological Wall of Troy, it's clear enough to anyone that it acts as a gatekeeper, but it should also be clear that this, like any defense such as the skin & nose hair, is the hallmark of an evolutionary arms-race -- in this case against living things small enough to pass into the bloodstream: microbes. Because the latter are also evolving (unlike the rain & dirt that our skin keeps out), and much faster than we are, all they need is to stumble upon a mutation for smaller size to squeeze through, or evolve a neurological cannon to blast through our Wall; or perhaps a neurological Trojan Horse would suffice. We would then evolve a better Wall, and the cycle would repeat. Our BBB is not unique in the animal world: it protects the nervous systems of vertebrates and insects, a testament to the ubiquity and eternity of the struggle against pathogens. See my previous post here on the recent Wang et al. paper which showed that among the genes that have undergone rapid recent selection in humans are ones that have to do with pathogen response and neuronal function.

The brain uses up 20% of the body's energy, so that's quite a hot spot to hit if you're hungry. More, if the human host is a mere vehicle to transport you to the real host, you want to get your hands on the main control levers to get you there. Homo sapiens have inhabited the Earth in their roughly modern form for ~500,000 years, always swarmed by varying degrees of bugs, so the odds that zero of them have shrunken themselves or stumbled upon a cannon or Trojan Horse to bypass our most recent version of the Wall is -- well, about nihil. To name just a few obvious culprits, with presumably many more unidentified: the neurological symptoms of African sleeping sickness result from the protozoa Trypanosoma brucei crossing the BBB; in people with compromised immune systems (mostly from AIDS), the common JC virus cannot be held in check and is free to cross the BBB, causing progressive multifocal leukoencephalopathy (PML); and bacterial meningitis seems to use a Trojan Horse strategy to cross the BBB of newborn infants. So, right after you're born, the bugs are already digging in, and they never leave you alone. As an aside, the nucleus affected in gay men and sheep belongs to the hypothalamus, a part of the brain which lacks a BBB. Also, any drugs designed to act on the brain bypass the BBB directly or indirectly.

It's easier to recognize when things are screwed up than when they're working normally, so we mention the evidence above only to show that in the evolutionary arms-race, the bugs (not surprisingly) have figured out how to bypass our latest version of the Wall. In principle, more difficult to detect flora could be doing so in order scratch our back if we scratch theirs, much as the mutualist gut flora make a bee-line for our colon not long after we're born. In the next post, we will briefly discuss how a germ could help someone become a genius.

February 3, 2006

Politically incorrect fashion III: Gayness

In this last installment, we investigate the gay impact in the fashion world. Why are gay designers the bane of those who want to discredit the notion that gay men tend to be more effeminate than straights? Just what makes a male gay anyways? Are gay men more artistically gifted on average than straight men? If so, is that due to whatever causes their homosexuality? And so on. Soon in this blog, we will tie together some of the threads in this series into an argument for creativity being just another "flavor" of g, not another general factor alongside it.

First, fashion is a gay field, not merely homosexual. And these are not just any gay men -- they evoke images of "girly" gay men, for example Carson Kressley from Queer Eye. Is this just because they conform to the role society expects them to play? Not at all. As we mentioned before, men have greater visuospatial (VS) skills than women, reflecting differences in exposure to testosterone in utero. But that's not all, as VS skills peak at a testosterone level somewhat below the male median (yet significantly above the female median). Therefore, if males are screened for high VS levels, they will be more feminine than average. The same goes for straights: back in high school, did the arty kid who was always drawing strike you as having testosterone levels like the jocks who beat him up? More masculine than feminine, for sure, but definitely feminized for a guy.

But hold on, just what makes a guy gay in the first place? Any discussion of patterns among gays must take this into account. While the answer is not known, available evidence suggests Paul Ewald & Gregory Cochran's hypothesis that it is caused by a microorganism ("gay germ"). The basic logic is simple: homosexuality causes a huge fitness cost (gays have ~80% fewer kids than straights), has been around for at least several hundred years, and shows up in ~3% of all men. If it were caused by genes, they would be rapidly selected out so that it only showed up on the order of 1 per 10,000 (the highest random mutation rate in humans) unless 1) homosexuality compelled gay men to raise at least twice as many nieces & nephews as a straight man raises children (thus ensuring that copies of their genes make it into the future), or 2) it protected single carriers from some nasty infection.

As for 1), there is no evidence empirical or anecdotal for this view; if anything, gay men appear less eager to raise a family than straight men. As for 2), the infection protected against would have to be on the same order of nastiness as falciparum malaria, yet it would have to strike large swaths of Europe & North America. There is currently no evidence that single carriers of the purported gay gene(s) are protected from this purported disease. That leaves environmental causes, and since homosexuality predates exposure to modern toxins like tobacco, a microorganism is the most likely source. Also, more often than not, when one identical twin is gay, the other is not. Another popular environmental biological hypothesis, relating to sex hormones in utero, may account for some but far from all cases of male homosexuality. See more detail from Cochran here and here (pdf), as well as this summary by Steve Sailer. There is no direct evidence of infection (largely because such research would never be funded), but there is plenty of indirect evidence, something lacking in alternative theories. One need not have to have isolated the precise gene that causes Sickle Cell to recognize the pattern of how it shows up in families, pointing to a genetic cause.

All that said, when I checked my list of 13 super-elite gay & probably gay male designers (i.e., gay but never came out, as opposed to of unknown sexuality), only 8 were born in winter (Dec-Feb) or spring (Mar-May), the seasons during which infection in infants is most likely. And because my Canon list is not perfect, even this meager result could be a fluke. This replicates a negative result for seasonality among gay male births run by a reader of Steve's website (here, Ctrl F "setback"). However, as Cochran noted in response, this only shows that the probable infection doesn't strike right after birth; because gayness shows up before puberty, that still leaves almost a decade to be exposed. So, seasonality of births is sufficient to suspect infection (as with schizophrenia), but not necessary.

Then might this microorganism have an effect elsewhere in the brain, partially boosting their creativity? Before answering this, we must sketch our concept of what creativity is, an outline which we will fully flesh out soon in this blog. Common definitions posit that creativity is the ability to devise novel uses for existing creations, or to solve an unsolved problem by thinking unconventionally. In our view, the conceivable solutions to a given problem form an unbounded, very rugged landscape, with valleys & peaks representing unsatisfactory & satisfactory solutions, respectively. Due to finite cognitive resources, attention to detail when observing the landscape is restricted by a "spotlight" defined by a center and radius (roughly, focus and scope, respectively), both hardwired by natural selection (via the Baldwin Effect) to make solving problems quick & good enough rather than baroque. A flexibility constant for the center (FC-C) describes how far the spotlight's center may stray from the instinctual cue -- a lower FC-C indicates low tolerance for deviation from instinct (mediated by a negative feedback loop), while a higher FC-C indicates high tolerance for novelty. A similar FC-R describes how tolerant the system is of deviation from the built-in setting for the radius.

The FC-C of creative individuals is high; they are thus weakly attracted to the "obvious" solution, thereby freeing them to focus on other regions. Their FC-R is also high, more weakly stuck to the "narrow scope" setting, thereby illuminating even more of the surrounding landscape. Able to survey more of the terrain, creative people are able to spot local maxima that are higher than the local maxima noted by ordinary people -- in particular, creative people locate local maxima that ordinary people would never roam near because the latter's spotlight cannot show them that beyond the vast valley they perceive in some direction, there is actually a higher peak. This ability to perceive what others cannot is what inspires awe: "How on Earth did a human being ever think that up?"

We illustrate this with the top two designs from episode 8 of Project Runway. The challenge was the strongest test of creativity so far: each designer had to explore Manhattan, snap photos of anything that inspired them, choose one, and design a garment around the idea. Totally open-ended. The winning design, by Daniel Vosovic, was "Japanese sleekness" (pic here), a narrow stretch tweed skirt suggesting a minimalist vase he'd seen, and a silk organza top evoking the orchid bud he saw in the vase (distinct from merely copying the bud into a floral pattern print). It looked more wearable on TV, but again the purpose was to showcase their creativity. The lost-by-a-hair design, by Andrae Gonzalo, was "Dirty gutter water" (pic here), which despite the name was not performance art. His inspirational photo was of gutter water that created beautiful colors when struck by the sunlight, and whose jagged concrete pebbles glistened like jewels. I'm not kidding -- it was a pretty picture. He designed an evening gown cut on the bias and used a toned down yet seductive color palette, with some asymmetrically placed metallic pieces to suggest the "jewels." Again, it looks more stunning on TV since you can see the full length of it, and as the judges remarked, it looked like it cost far more than the $100 budget.

In their comments, the judges noted that both were beautifully conceived & executed, the only difference being that the orchid design took inspiration from an unnoticed yet typically beautiful thing (orchids in a vase), whereas the dirty gutter water dress began with something repulsive and transformed it into something beautiful without being overly sentimental. Neither was too literal, nor an obvious approach -- in fact, the judges berated Kara and Zulema for finding obvious solutions. For comparison, if an average person and a superb composer were to create a piece inspired by a fish, the former might tape-record the sound of actual falling water and the sound of fish swimming through a stream, whereas only the latter would devise a figurative fish-swimming-through-water melody (as Schubert did in his Trout Quintet). While the tape recording of fish swimming may soothe us, only the Trout inspires a sense of awe.

It will shock no one to learn that both Daniel & Andrae are gay white men. Indeed, of the 8 males selected to be on the show, 7 are gay white men. All of the male judges / mentors have been gay & white. And to reiterate from the post on sex differences, gay men are ~22 to 36 times overrepresented in the elite Level 3 of the fashion world. So the question is: is this overrepresentation more than we would expect given only that they are white men? That is, does being gay boost their creativity? Unfortunately, we have no quantitative way of figuring out how much is due to straight men with high VS skills staying away from fashion for personality & temperment reasons (and thus flocking to architecture), and how much is due to putative differences in creativity. In 100 years or so, the data may be in, but as of now, we remain agnostic. We know they are no less creative than straights, reflecting the fact that creativity is likely another secondary "flavor" of g, and as far as we know homosexuality doesn't depress IQ. My experience suggests a slightly higher expected value for gay male IQ. As a thought experiment, imagine you are asked to guess the IQ of a randomly chosen Af-Am male. Your expected value would be ~85, the population median for Af-Am males. But what if you were updated that he was also gay? Would your expected value remain the same, indicating independence of homosexuality and IQ within a race? My answer is that it would increase somewhat (~5 points), but I'm not sure how much consenus there would be on this puzzle.

Let's suppose it does turn out that gay men have slightly higher IQ, or the same IQ but a higher sub-score on creativity. How would that fit in with the "gay germ" theory? Well, the very fact that gay men are no dumber than straights shows that the bug has highly localized effects, though in an interconnected brain these subtle changes may result in larger discrepancies with straights. One of Cochran's ideas is that the bug just changes the search image in the program for finding mates -- by all cog sci accounts, that "module" of our mind has plenty of sophisticated, hard-wired machinery, part of which has to be some search image, lest we waste time courting cats or rocks. The strong version: the gay germ resets the location of where the center of the spotlight focuses when solving the problem of who to court -- it is still narrow in radius, FC-C & FC-R are still low (gays can't budge themselves into hetereo territory), but the spotilght is focused on the "male" rather than "female" region of the terrain. By contrast, bisexuality would result from tweaking the dial for the radius to encompass multiple regions of the terrain simultaneously. (Though in men, bisexuality is likely rare among non-straights.) This shift in focus could be inherited in other problem landscapes -- gay men would be compelled to focus on areas straights are not. However, the shift in focus could only apply to a narrow subset of problems the person must solve. For example, if the shift were allowed to apply to food, gay men might spend most of their time trying to eat dirt & glass, ignoring healthy foodstuffs. The shift would only occur in the cluster of problems directly linked to the basic one of finding a mate -- creativity in art, etc. would be analyzed as conspicuous secondary sex characteristics, somewhat like Geoffrey Miller has proposed, and thus directly linked to mate acquisition.

If this sounds too fanciful, a weaker form says that gay men demonstrate compromised immune systems w.r.t. at least one microorganism that affects the brain, so perhaps they are more likely to be so infected by similar brain bugs, one of which tweaks the defaults for the center, radius, FC-C, FC-R, or any combination. That may sound odd, but before long on this blog, we will argue that "mad genius" is in part the result of an early infection. We already know from behavior genetics that somewhere around 50% of the variation in intelligence & personality is explained by differences in the "non-shared" or "unique" part of the environment, which includes things like exposure to the limitless bugs that inhabit our world and colonize our bodies. We also have solid evidence from rats that toxoplasma gondii, when it reaches their brains, either "switches off" or "dials down" their instinctual fear of the smell of cat urine, resulting in an otherwise normal rat but which doesn't run away when it smells its natural predator nearby. I'm not suggesting t. gondii is the "gay germ," mind you.

That said, my take is that whether or not they are more creative, gay men are certainly more industrious in following their calling. One common theme in recent intellectual history is that the world of fine arts -- particularly the visual arts -- has been going down the shitter since World War II. And not just accidentally & helplessly but by deliberately self-eviscerating. Take this representative quote from abstract expressionist Barnett Newman's 1948 The Sublime is Now: "The impulse of modern art is the desire to destroy beauty." He was no Dadaist prankster. Still, his verbal formulation of the sublime replacing the beautiful -- despite being a sexy slogan -- resulted in some of the most sterile art ever conceived. Imagine going to the modern wing of your local Big Gallery (for me, the National Gallery) and seeing this, one of 12 nearly identical canvasses from Newman's Stations of the Cross, which occupy a large room all to themselves. See footnote [1] for my tangential rant on Newman. Though I won't elaborate on the point, much the same could be said of lots of Big Names in modern architecture w.r.t. their views on beauty.

Whether or not a new generation of artists decides to rescue beauty, for the many decades during which the art world has lain comatose, a group of designers both famous and anonymous have continued to emphasize beauty: fashion designers and interior designers, disproporionately gay men. Only time will tell what their role has been -- whether to mostly preserve & somewhat innovate with the classics, like Arab & Jewish scholars did with Greek classics until Renaissance scholars took them in entirely new directions, or whether these gay male designers will themselves prove to be the Renaissance figures. In any event, for right now they're far and away the only game in town if you're bored of burdensome, belaboring beauty-bashing.

To conclude on that note, what are we then to make of theories such as those of Rodney Stark and Charles Murray who posit that in order for creative people to realize their full potential, a necessary condition may be some kind of monotheistic religion that stresses that one's purpose in life is to use God's gifts (such as intelligence) in order to please him? Part of this argument stemmed from the observation that when individuals see less divine purpose in life, creative output per unit of population declines: the peak during the Renaissance sank steadily unto the nadir of the secular 20th C. Again, only time will reveal how religious these gay male designers were, but the elite members don't seem particularly devout -- not only due to antipathy toward homosexuality in the Catholic church (remember, these Big Names are largely French & Italian), but due to their larger emphasis on living la dolce vita, God or no God. So, while the strong form of the monotheistic argument seems false, a weaker version may be true, namely that for creativity to flourish, people must see a purpose in life, regardless of who or what is telling them what their purpose is.

[1] It is the most hilarious thing to watch visitors when they end up in Stations room -- they don't want to just walk right through lest they be condemned as philistines by the art snobs peering at them through hidden cameras, yet with no other canvasses within pacing distance, they have little choice but to plod through this gauntlet of reciprocal blank stares. This is not an unrepresentative work -- it is considered the peak of Newman's oeuvre and is intended to be a memorial to Holocaust victims. Typical of medicore artists, the actual work is pedestrian, and only the verbal (rather than visual) dexterity of the artist saves it from oblivion with clever titles and linguistic bullshitting when explaining it. Despite his pretensions to humility and meditation, Newman's ego was as limitless and featureless in its expanse as his yawning, barren canvasses. Thumbing his nose at aesthetics, he remarked that the study "is for artists what ornithology is for birds." Perhaps a more apt analogy from zoology would be that abstract expressionists of Newman's stripe are for the art world what the zippy, hanger-on pup is for the nonchalant, majestic bulldog in cartoons ("Heh heh heh heh heh, whadda we gonna do today boss? Heh heh heh heh?"). And if he's correct that "A painter is a choreographer of space" -- and I think he is -- then it would appear that someone has drugged his ballerinas with horse tranquilizers. Lest others think I'm being unfair to a nonconformist, Newman's approach is merely facile. To borrow an image from music, if we plotted melodic skill vs harmonic skill, some artists score high on one & low on the other, some score high on both, but Newman's data point would barely be distanced from the origin in any direction. His is no Zen monk's watercolor, bonsai tree, ikebana arrangement, or other form that truly emphasizes harmony.