Thursday, February 18, 2010

I Wuzzint Doin It Right

So my surgeon's partner is yanking on my toe with a great big frown on his face.

“There's less flexibility now than there was last time. I'm going to write you a prescription for physical therapy.”

I think I managed not to groan. It isn't that I really mind physical terrorism — I'd done well playing through the pain before the surgery, and doing the same through far less pain afterward. But we're talking about the Little Piggie that Went to Market. I am kind of known at this podiatry practice as the Patient Who Does So Well because He Always Complies; but really.

Still, Mister Compliant took the scrip in hand, showed up at physical therapy, and was lectured on how, really, a stiff big toe can completely mess up your gait and your sense of balance.

“But I have no sense of balance,” I said, “Never did.”

The doc who runs the PT practice overheard, and swooped in for a test. It's actually not uncommon for folks with a hinkey middle ear to do things like ski, mountain bike, and climb — they just (over)compensate using vision and by feeling the floor (proprioception). But we soon found out I was not one of these.

While I tried to balance on one foot, the doc observed that I wasn't actually doing badly at all — but I was maintaining my balance too much using my ankles and not enough using my toes.

“You have to dig in with the toes to maintain balance,” he said.

The man was telling me I'd never learned to stand properly. I felt like a Lolcat poster:

Standing still: Yer Not Doin It Right

Well, maybe there's more than that I haven't been doing right: hence today's entry, from Brian Duistermars and Dawnis Chow of Mark Frye's lab at UCLA. Using a wind tunnel, they tested whether fruit flies could turn in the right direction to find a scent source when an antenna on one side or the other was “occluded” with a tiny little glob of glue.

I kid you not.

This kind of research nearly always truns up a couple of surprises: for one thing, the flies are left handed: blocking the left antenna affected their ability to find the scent more than blocking the right. The Johnston's organ — the middle part of the insect antenna, which detects motion, unlike the outer part that detects smell — is necessary for proper turning into the scent, though not its detection.

But maybe the most amazing part of the experiment was that it worked at all: that flies need two antennae to track the direction of a smell in the wind, and that therefore it's possible to detect a difference of smell between antennae that are less than a millimeter apart.

To help me wrap my head around this, I actually emailed Mark Frye to ask him whether that inference was really warranted. He said yes, but threw a further monkey wrench:

“If you calculate the mean molecular concentration gradient across the fly antennae it is on the order of thermal flux (noise) ...”

So somehow the little bastards are detecting a difference against a noise background that's as loud as the signal.

Now, I've been bloviating on the dog lists for some time now about how I'm having trouble seeing how a dog's nostrils, which draw scent from about three inches apart, can detect a usable concentration gradient. I'd say the fly results pretty much put any doubt to rest.

Having said that, it occurs to me that what I was tripping over had less to do with whether they could detect a smell difference across that distance than how it would be useful. To see why that's an issue, let me explain how our understanding of what smell looks like has changed since the 1980s, when the scent theory explanation that most dog handlers have read was published.

Starting from the idea that, as wind blew scent along, it would diffuse outward and mix with the surrounding air, creating what we call a “scent plume:”

If you look at how the scent gradually decreases with downwind distance, there's a very subtle change that would be incredibly difficult to detect.

But wait; folks working with smoke in wind tunnels have found out that that old picture of a scent plume is vastly oversimplified. In reality, as the scent mixes with surrounding air, it does it turbulently. Think of how, if you stir a black coffee and then drip cream in, it doesn't mix evenly. Stronger chunks of cream remain visible for a while. Same thing with cigarette smoke, or a smokestack. The real scent plume looks like this (and note you can see a much better drawing, for which I wasn't able to get reprint rights, in this paper):

So even though I had the correct picture in my head of a filamentous scent plume, with really strong chunks of smell interspersed with increasingly large voids, I wasn't putting it all together: dogs don't have to detect subtle scent gradients — or at least not that subtle — because such gradients essentially don't exist in nature. All the pups need to do is detect the transition from no smell to strong smell and back, as it sweeps past: and for that, a different signal in each nostril actually does provide important information.

'Course, it's not as simple as turning toward the stronger scent, like you would in the “old” scent plume. If a filament has just swept by you, that would be the wrong direction. But by checking which nostril got the smell when, and what direction the wind was blowing from, you can develop a more involved strategy, something like the ones seen in insects and birds and fish — and unless my own, humble and as-yet-anecdotal observations are way off base, search-and-rescue dogs as well.

For the flies, that signal-to-noise problem still stands. But at least, finally, I think I may be on track to “doing it right.”

Tuesday, February 9, 2010

Phil Klass, aka William Tenn

I made a jackass of myself the first time I interviewed — hell, spoke with — Phil Klass.

“You have no idea who I am, do you?” he asked, frustrated, after I’d posed a few questions over the telephone. I hadn’t yet connected him with his pen name.

To be honest, I hadn’t read much William Tenn at that point, even if I had known he and Phil were one and the same. And as a relative newcomer to Pittsburgh, I didn’t yet have an internal map of the local SF community’s leading lights. It wasn’t until later, when I looked Phil up in the Encyclopedia of Science Fiction, that I tumbled to how badly I’d blown the interview, which the Pittsburgh Post-Gazette had assigned me by way of covering ConFluence, the city's major SF convention.

For all his multicultural sophistication — he went to war as a socialist, Jewish U.S. soldier, the son of a Brit and a Russian — Phil Klass was an American original. He embodied so much of what makes me proud of this country. He had his opinions, and stated them courageously no matter what anybody thought; during the McCarthy era, he was one of a few SF authors openly parodying the Red Scare. He claimed no special courage, on the grounds that the folks who would have objected didn't read, and wouldn't have understood, science fiction.

Having done some intelligence work on captured Nazis, and despite the fact that he and they were each other's worst nightmares, Phil had utter contempt for torturers and their ultimately craven arguments of “utility.” Yet he told a story about dragging local townspeople in to see what had been happening in the death camp next store to them, belying their claims of “not knowing.”

Phil also told a captivating story of a major SF editor of the classic era — I think it may have been Campbell, but I'm not sure — confiding in him that “Jews probably are Homo superior” — an embarrassingly common trope of SF in its sophomore years — and how, despite his best attempts, he couldn't get the man to understand why this was so wrong, how it insulted rather than honored the memory of the Holocaust's victims. “I told him I was sorry to hear that, because it meant we'd learned nothing,” Phil said decades later.

Phil also was generous in advice, and gave good advice. I wish I could tell you how his tips transformed my SF career — but sadly, the industry is too much of a train wreck for anybody to provide the magic words. Suffice it to say he was bullish on nonfiction, bearish on creative nonfiction, and absolutely gloomy on science fiction. I've seen nothing to indicate that he got anything even slightly wrong in that.

Of course, Phil Klass, under pen name William Tenn, was a gifted science fiction author, a David-Bowie-like figure who maybe didn't get read as often as the Asimovs, Heinleins, and Herberts, but who was read by, and influenced, just about every subsequent major SF author. He was as honest in his fiction as he was in real life, arguing at a time when SF stories typically had genius inventors creating the first moon rocket in their back yards that it was going to take the finances and physical resources of a large government bureaucracy to reach the moon. It pissed people off to have someone puncture a cherished trope like that, but I note that it was a bloated, inefficient, can't-do-anything government agency called NASA that got the job done, and not private-sector venture capitalists.

But I digress.

Going over my notes from that first interview with Phil and my subsequent research, I had an inspiration: I would fight my every instinct. Rather than side-step my cluelessness, I would confront it. I opened the article with Phil’s exasperated words. It gave me a perfect entree into talking about the many reasons people come to an SF convention, and the uphill battle those of us with the SF-writing compulsion face.

After the piece ran, I ran into Phil at ConFluence, and introduced myself. He said simply, “I read your article, and it was mostly accurate. I was surprised!”

Phil, wherever you are, I'm going to take that as an indictment of modern journalism. That’s my story, and I’m sticking to it.

Sunday, February 7, 2010


Literally snowbound, it's hard to come up with excuses not to blog. And I suppose, on a frigid day, it's not too unusual to be put in mind of old flames.

Mind you, this wasn't someone I actually dated — more an unrequited torch, before th'wife, even before the Before Time. We're talking what cosmologists call Deep Time, back around the point when God was thinking maybe the neutron might be a good idea.

Her name was Kathy Ewing, and she was my Self, Culture, and Society lecturer at Hogwarts [1]. She was young, pretty, and smart as all get-out — and I had a fantastic crush on her, though doubtless she wouldn't remember me at all by now.

At least, I hope to God she wouldn't, the reasons being imminently obvious.

Required background: Like many of the common-core courses [2] at the University of Chicago, Self, Culture, and Society had two hour-and-a-half discussion sections each week, in which Kathy and about a dozen of us would discuss, argue, and hash out the course materials — in this case, a “Great Books” [3] mix of psychology, anthropology, and social science.

A side-note: the U of C is the intellectual equivalent of someone throwing a knife to you and hollering, “Now, come at me!” It's exactly the kind of place that pussy little right wingers like to bitch about being hostile to their ideas — only they're missing the point: it's hostile to everybody's ideas. It's all about forcing you to defend your beliefs, structure your arguments so that they make sense somewhere else besides the addled interior of your head ...


I don't remember whether it was every week, every two weeks, or what, but every once in a while all those little discussion sections met in a big hall for a lecture. The professors and lecturers teaching the study sections [4] would rotate this duty, each taking, I suppose, a topic of particular interest or expertise on which to hold forth.

So this particular upcoming lecture was Kathy's, and I was determined to sit front and center, nodding sagely at all the appropriate points, impressing her with my interest in her topic — and, strange as it seems now, thereby my interest in her. Not that I had it planned out even that clearly.

Only the night before, a good friend who will remain nameless had the latest in a series of fights with her boyfriend, another nameless good friend, and I spent much of the night and next morning sitting in a stairwell offering fantastic advice [5]. Didn't really get any sleep to speak of that night.

So picture me the next morning, bleary eyed, too late to get coffee at the dining hall, stumbling into the lecture hall, only just barely conscious enough for a fogged corner of my mind to remember the plan of the previous day.

Unfortunately, all it remembered was, “Sit front and center.”

I'm sitting there, then, about 10 minutes into Kathy's talk when the realization comes over me that there's no way I'm staying awake. Just can't keep the eyes open. I did my best to hide it — the old, cover-your-forehead-with-your-hand-while-you-look-down-at-your-notebook thing, the hunch-down-over-the-table thing, every trick I could think of. Needless to say, even five minutes afterward it didn't seem likely that I'd had much luck at hiding from Kathy that I was sleeping through her lecture.

Dashed expectations are the subject of today's entry, a bit from C. Eisenegger and pals at the Institute for Empirical Research in Economics in Zurich and other environs, about testosterone.

Now, in the words of Robert Sapolsky — of whom I'm an admirer — in his wonderful essay The Trouble with Testosterone, here's the gist of the results when you inject testosterone into a submissive male monkey:

“Take that third-ranking monkey and give him some testosterone. None of this within-the-normal-range stuff. Inject a ton of it, way higher than what you normally see in rhesus monkeys, give him enough testosterone to grow antlers and beard on every neuron in his brain. And, no surprise, when you check the behavioral data, he will probably be participating in more aggressive interactions than before.

So even though small fluctuations in the levels of the hormone don't seem to matter much, testosterone still causes aggression, right? Wrong. Check out number 3 more closely. Is he raining aggressive terror on everyone in the group, frothing with indiscriminate violence? Not at all. He's still judiciously kowtowing to numbers 1 and 2 but has become a total bastard to numbers 4 and 5. Testosterone isn't causing aggression, it's exaggerating the aggression that's already there.”

So you get the background here: testosterone as a vehicle of aggression, of conflict, if not social dominance.

Imagine Herr Eisenegger & Co.'s collective surprise, then, when they gave sublingual testosterone to a bunch of women [6] and then had them play one of those social-strategy games: In this case, they gave one woman $10 [7] and told her that she had to make an offer to another — to give that other woman $5, $3, $2, or nothing. If the second woman refused the offer, nobody got anything. If she accepted, she got what was offered and woman number one kept the rest. So there are two separate motivations: the less woman one offers, the more she gets to keep; but if she doesn't offer enough, woman two can play the spoiler.

The expectation, of course, is that testosterone will bring out woman one's inner total bastard, to use Sapolsky's words, and offer less, even at the risk of losing it all.

You've probably guessed that it didn't come down that way: in fact, testosterone made woman one offer not less to woman two, but more. On the average, she offered about fifty cents more than when she hadn't been given the testosterone.

This isn't necessarily a surprise; some experts the investigators had polled beforehand had actually predicted this result, on the grounds that testosterone would enhance the women's desire to take leadership: and one way to establish leadership is to make a more generous offer that makes the other gal more likely to trust and follow you.

But that's not the interesting bit. Eigenegger etc. then took their data, and sorted it differently. Instead of separating the “women one” who'd gotten testosterone vs. those who got a placebo, they separated by which of the two the women thought they'd gotten. And guess what? The women who thought they'd gotten testosterone acted, if not like total bastards, then at least like bastards: on average they offered a dollar less than the women who thought they'd gotten placebo.

That's right, the expectation of testosterone was more potent in terms of both size of effect and statistical significance than the real thing was. And it had the opposite effect of the real thing. For all the world, it looks like testosterone's bad rap in popular culture carries more weight than its biological effects in our little brainbones.

Deep waters here: did expecting testosterone make gals one a bit on the bitchy side, or did the bitchier girls expect they'd be given testosterone? And since the anti-placebo effect was stronger than the real thing, what thence?

Our authors did a bunch of work to control for various complications; you can read more about it in their paper. As always, a single experiment isn't going to be gospel. But it does give us a wallop of a lesson in being careful about our expectations.

I don't know what expectations Kathy had of me, if any — for obvious reasons I never had the guts to ask her about that day. But I got a disturbing window on the question a few years later, as a senior, when I ran into a fellow student from Kathy's study section.

When we figured out that we'd been in the same class, his eyes first narrowed, a bit angrily. Then the light bulb went on, and he said, “Oh, I remember you — you always asked the stupidest questions!”

Oh well; expectations be damned.

[1] A prospective student I was interviewing for the college put this metaphor into my head. Geeks surrounded by stone: God, yes. At Harvard, Heather may have been a resident tutor at Slytherin, but we had Lord Voldemort — I mean, Milton Friedman.
[2] U of C is one of those liberal-arts-and-a-bit-angry-about-it places — everybody shares the same common core of science, social science, and humanities courses before they get to take their major requirements and electives.
[3] Mostly dead white European men, though there were a few chicks in there —
Mary Douglas and the like. And I understand they've been broadening it since.
[4] And I think most of them actually were lecturers or professors of varying type, and not grad students — that's another thing U of C is serious about to the point of it being a “thing.”
[5] I don't know what's harder to believe — that we actually did this, or that anybody would want to hear my advice.
[6] This, of course, is a loose end to the study: would the result have been different had you done the experiment with men? It's a quandary, though, since in men there'll be a normal variation between individuals and from day to day, and so, like the monkey, you have to give a snoot-load of it to make sure you're significantly changing what's already there — and then you have to worry about non-natural effects of what amounts to an OD of testosterone. And they won't let you do that with humans anyway. Women, at least, are more of a blank canvas, though you do have the possibility that their brains won't react in the same way that mens' will.
[7] Actually, it was “monetary units” — maybe euros — but you get the idea.