Monday, December 29, 2008

Now Wait a Minute ...

It was exactly the kind of search that members of our all-volunteer team are not supposed to be doing: A missing despondent, spouse couldn’t account for all the guns in the house, and a very suburban setting to boot. It’s what we simply call a “law enforcement search,” three guesses who has the training, equipment, and authority to conduct it.

Having said that, just because we couldn’t look for the subject didn’t mean we couldn’t help at all. Our folks took places in the incident command post; among other field-search specialists, Barbara Butler, then a rookie member of our team, and I accompanied a local law officer on a house-to-house survey of the neighborhood, to find out if anybody had seen our guy.

I scored some points out of the gate, by asking the officer if he knew if anybody in the neighborhood was out of town or of any houses otherwise unoccupied. He realized right away what I was getting at, and drove us over to a house that we canvassed quickly to make sure there weren’t any open or unlocked doors or windows. Dead end, but it’s always good to be pitching ideas they like [1].

It was also a bit of an education as to how the world looks to our law-enforcement colleagues: I recall our reception at one house. The officer had commented on these folks being frequent fliers, as it were, and they were bristling with hostility the instant they saw the squad car pull up. But when he introduced us as the department’s search-and-rescue team [2], and it became clear we were looking for their missing neighbor and wanted their help, not to roust them, they brightened up and did what they could. They hadn’t seen anything, but I like to think it may have helped both family and cop down the road to have had at least one interaction that wasn’t adversarial.

But the reason I bring this story up is what happened just as we were saying goodbye to those folks: the officer’s radio crackled with the news that a state trooper had found our guy, not too far from where we stood. Barb and I piled into the back of the cruiser and got quite a ride.

As we careened down the suburban avenues, lights and sirens going, other local and state police cars filed in with us until we were something of a parade. It was fantastic, like being the cameraman for an episode of Cops.

So we pull up to the verge of a small, wooded local park, and the officers pile out of their cars, running into the woods. I don’t think that at the time I knew the full story — that the subject had come at a state trooper with a knife — but it was pretty clear that the situation was their bailiwick. Not for us untrained, unarmed volunteers.

Barb is walking after them.

My hand comes down on her shoulder: “No you are not,” I say, in what probably wasn’t the only time I’ve pulled rank on a junior team member, but may be the only time it ever worked. A few minutes later, we see the police escorting the guy to one of their cars — the trooper had had a Knock on Wood [3] moment and come through with flying colors, disarming a mentally ill subject without having to hurt him.

This is not to pick on Barb, by the way: in the rush to go help, rescuers often get themselves into situations they can’t handle. Tunnel vision kills rescuers: that’s why it frustrates me when everybody lionizes a local rescuer who leaves a widow(er) and kids behind attempting something he or she wasn’t trained to do. You’re always supposed to survey any rescue scene and make sure there isn’t a situation that could make you patient number two; you’re always supposed to stay within the limits of what you’ve been trained to do — and just because people make understandable, very human mistakes, teammates are supposed to rein you in now and again.

All the best intentions aside, somebody just has to say, “Now wait a minute ...”

Enter a paper from last year on ground-scent tracking by humans, which came to my attention again because an automated PychINFO search tagged it (possibly because it just entered that database). The leaders of the multi-institutional team that did the study were Jess Porter of UC Berkeley and Noam Sobel of the Weizmann Institute of Science in Israel.

We have to keep one big thing in mind: These guys were studying whether humans could follow a ground trail, much as a search-and-rescue trailing dog does, mainly because they wanted to study the phenomenon of ground trailing with the benefit of subjects that can tell you what they’re thinking and what strategies they’re using, and will accept all sorts of nose and head attachments that might get you bit by other subjects. On these terms they succeeded amply [4].

The idea was simple: Could they produce a trail of a scent that humans can detect — chocolate — that humans could follow, without the use of their eyes or other senses? And what would that experience teach about how other species follow ground scent?

The short answer: People could not only learn to follow a chocolate scent on the ground, they could get much better at it with practice. Even more interesting:
* Just as in dogs, a higher frequency of sniffing allowed a more accurate and speedy trail.
* As in critters as different as maggots and rats, both nostrils have to be in play for a good, efficient trail, further cementing the human subject as relevant to what the animals are doing.

The latter observation was particularly interesting from the SAR perspective, because it isn’t at all clear how two nostrils, right next to each other, can give you any useful information about which direction to move along a trail. How can a dog’s nostrils, maybe an inch apart, tell you anything about the age of scent in either direction when the microscopic skin particles that carry ground-based scent are only a fraction of a second older than those an inch farther down the trail?

The human subjects simply told Porter, Sobel et al. how they did it: They worked along the edges to keep themselves oriented, in much the same way that a smoke-blinded firefighter sticks to the wall to keep form losing his way in a burning building. And much the same way a number of species follow airborne scent plumes. And for that, the small separation of vertebrate nostrils is more than wide enough, as the outside edges of a scent plume can be fairly sharp.

So this pretty much looks like a win for nurture over nature, right? Maybe humans can become good enough at scent tracking to do without the bloodhounds? Even the researchers said their findings “... suggest that the poor reputation of human olfaction may reflect, in part, behavioral demands rather than ultimate abilities.”

The moderation of that statement with “in part” aside, there’s only one problem with this idea, and it’s where the nurture-conquers-all take starts to fall apart. Instead of leaving trace scent on the ground, which is what SAR dogs follow, the researchers used a string soaked in odorant to create their “ground scent.” That means that, instead of the scent impression left behind by a moving point source of scent, which is what a SAR dog has to trail, their subjects were traveling along a linear source of relatively constant scent. The ersatz trail doesn’t vary nearly as much, if at all, in age and, presumably, intensity as you go along. This isn’t immediately important to the researchers’ findings, but it does cast a shadow on the the long-term relevance (though they could re-design the experiment to get around this).

A string soaked in chocolate is a much stronger, more consistent scent source than a moving human being, whose microscopic debris are hitting the ground in a ragged path partly dictated by crosswind and possibly varying quite a bit in intensity as it goes along. The humans may be able to do the scent-string task, and they may even get good at it: but it’s not the same job the dogs do. And when you compare what humans can do with a continuous, presumably strong scent source versus a dog following a trace trail that’s a day or two old — this experimental design can’t even touch the subject of trail aging realistically — and you realize that the dog is achieving something vastly harder.

Worse, the information this experiment gives on how the human subjects followed the scent trail may not be relevant to real-life scent trailing: because the trail doesn’t vary along its length like a real one does, the directional cue is vastly different. The researchers dont say, but it looks like their subjects basically knew which way to turn once they hit the trail, they just needed to know they’d hit it — and to stay with it once they did. As such, the situation is far closer to that of detecting airborne scent plumes, as in the research I cited above and as airscenting SAR dogs do, than it is to ground scenting. That’s because in the former, there’s also a cue as to which direction to head when you hit the scent: the direction of the wind. For modeling ground scent, it maybe isn’t so germane [5]:

[Note that the scent actually takes the form of delicate filaments, not the dots I have here — I haven’t figured out how to draw that effect yet.]

Which doesn’t really constitute a serious critique of the present experiment — as I said, I think they can redesign it to be more realistic, and in any case they succeeded in meeting their initial goal of showing humans can trail at all. But it does remind us that something is going on between the dog’s prominent nose, ample receptor repertoire, massive olfactory bulbs, and who knows what else, that transcends anything our environment can do to help us use our smellers better.

And Barb? Well, she’s been with the team for quite a few years now, and unlike your’s truly, actually went through the official training and certification for incident staff members. At a search, she’s the boss of me.

If you want to know whether she’s ever had to rein me in, you’ll have to ask her.

[1] And you can bet that, if we’d found anything important, I would have happily given him the credit — local law enforcement are our clients.

[2] No, we’re not actually affiliated with that department. But I never argue when they take ownership of us — again, they’re our clients, and it’s a good thing when they want you. Our uniforms, by the way, were designed to look decidedly not like police uniforms.

[3] The version of the song I knew was
The Mighty Mighty Bosstones’, and it’s great — but I was surprised to find that it has a 42-year history I hadn’t known about.

[4] I’m not going to get into the difference between tracking and trailing as dog handlers use the terms, partly because you’ll get different answers from different handler, and partly because the design of this experiment obscures the issue.

[5] Without going into a ton of detail, a scent plume in the air — and probably a trail on the ground, since it’s in effect an imprint of earlier airborne scent — is pretty ragged and intermittent. Though it may seem obvious that you head into the stronger scent, in practice the direction of the stronger scent may be anything but obvious.

Tuesday, December 23, 2008

Latest Fiction Offerings

Happy Holidays.

Today I’m departing from our usual fare to update folks on my latest fiction projects.

I just received my author’s copy of the January/February 2009 issue of Cicada, which contains my short story “And Yet It Moves,” an historical piece on Galileo’s confession. This is my first resale of a story (it appeared in Paradox in 2003), and although it’s a departure from my usual science fiction offerings it is one of my favorites. The Cicada website no longer seems to allow you to buy single issues of the magazine, but I’ve found that most Barnes & Noble stores stock it; if they don’t, they can order it for you; just tell the salesperson that Cicada is the young-adult literary magazine published by the Cricket Magazine Group.

More of a professional risk on my part is A Matter of Gravity, my novel now posted to Briefly, A Matter of Gravity is a book about communication — and how understanding someone's language is crucial to unpuzzling his intent. Michiko Kawachi, a young linguist with humanity’s first-contact mission with the nont’h alien race, must decode the aliens’ language to prevent war — and discover a secret that will upend humanity's understanding of the universe. Please check out the link to the book, which will take you to the site that allows you to read and rank it.

The context: is an innovative site started by HarperCollins to allow new writers to bypass the slush-pile process. For those who aren’t familiar with the industry, the slush pile is the stack of novels they give to an under-paid, over-worked junior editor, with the instruction, “Find the good stuff: But if you take too long at it, or waste our time with books we don’t like, we’ll likely fire you within a year.” For a long time, many writers have suspected the slush-pile process was too overloaded to produce good decisions, and with so few publishers now accepting manuscripts from new writers it’s become rather hopeless even to get noticed, let alone read, considered, bought, etc. represents HarperCollins’ answer to the proposition that the slush pile process is fundamentally broken and needs to be replaced. They say they’ve had luck with it, in that by allowing visitors to the site to read and rank the books they’ve in essence recruited an army of slush-pile readers who may well be more representative of the general readership. Books that do well get considered for publication by HarperCollins: no guarantees, but at this point I have to say that if I don’t have enough confidence in my book to expose it to this process, well ...

So please check it out; you may also find other offerings on that you might want to read and rank. Heck, it’s free books to read, and you may discover your next favorite writer.

Monday, December 22, 2008

The Buzzer Buzzes On

Well. In answer to the question, “Would Americans still do this?” here is the answer.

I’m not terribly surprised that we did do this today — the memory of 9/11, and the ensuing feeling we had to let the authorities do whatever they needed to if we wanted them to protect us, is still fresh enough. You might say Abu Ghraib et al. might have taught us better, but then the original Milgram subjects had been reading about a Nazi war crimes trial in the papers just before recruitment.

I’m maybe less surprised than saddened by the fact that it was so easy for them to find subjects who hadn’t heard of the Milgram experiment.

“Did we need to repeat this experiment?” was the other question that immediately leapt to my mind. At first I wanted to say, “No,” but maybe the identical result it obtained argues otherwise. Maybe every generation needs to repeat this experiment, if Milgram was so easily forgotten.

BTW, check out my wife’s blog on this — I haven’t read it yet, but I think she may have a different take.

Tuesday, December 16, 2008

We All Pressed the Buzzer

I can’t believe I forgot another connection with yesterday’s alcoholism-treatment study — “Buzzer,” the amazing new song from Dar Williams, which I heard on the incomparable WYEP this morning while driving to work. It should be required listening for all human beings.

The song is about the Milgram experiment, a chilling psychology study from the early ’60s. Briefly, Milgram set the experiment up to look like a study of memory and learning in which the experimental (human) subject, called the “learner,” would be punished for wrong answers via an electrical shock delivered by another volunteer participant, the “teacher.” An “experimenter” monitored the process, telling the teacher when to up the voltage.

The trick was that the teacher, not the learner, was the experimental subject; and the study wasn’t about memory, but about people’s willingness, while the Adolf Eichmann war-crimes trial was still under way, to follow an authority figure’s instructions to do something awful. The learner was actually an actor, who received no electrical shocks but agonized and screamed and finally pretended to lose consciousness under the fake torture. If the teacher balked, he or she received the following set of instructions, with the experimenter escalating the commands for every objection raised:

1. Please continue.
2. The experiment requires that you continue.
3. It is absolutely essential that you continue.
4. You have no other choice, you must go on.

The shocking thing was, the experimenters got 65 percent of the teachers to go all the way to 450 volts, the point at which the actor lost consciousness. Only one teacher refused to go on before hitting 300 volts.

Turns out, under the right conditions, just about all of us are shits.

The Milgram experiment, like our alcoholism study, would probably never be approved these days. But though Milgram got his share of flak on ethical grounds, I think what this experiment taught us is too terrible and momentous to ignore, and probably in the long run justifies the damned thing. (Though some of the people who “verified” his results later on did things that make me angry, like doing it for real, with a puppy as the victim — and no, I’m not making that up.)

A lot of people know about Milgram; fewer know about what folks like psychologist Lauren Slater found out many years later. The teachers who went all the way, it turned out, weren’t the people you’d necessarily think, and neither were the folks who, at one point or another, refused to go on. One obeyer was devastated when he learned what the study had been about, and used the experience as a prod to change his life. He came out of the closet and became an activist for gay rights. One refuser went on to a long career in the military; and while I wouldn’t read too much into that, his reasons for stopping the experiment stemmed from the effect the stress was having on him, not out of concern for the victim. Two points don’t constitute much of a data set, but they show us that the details confound our broadest brush-strokes.

So here it is: We can all be shits. We all pressed the buzzer.


We all get to be individuals. We can choose to change ourselves, make ourselves more honest, braver, better. We can rise above our mistakes. Bilbo was meant to find the Ring. Hope isn’t the last refuge of the clueless.

And it begins with a one-syllable word, a word that comes easily when we’re two but not so much when we're 32:


Monday, December 15, 2008

By Any Means Necessary?

The noise damned-near deafened me as I entered the facility — a government-funded center for research on primates, placed in the boonies to avoid attention from animal-rights activists. In front of me stood a huge, Plexiglas enclosure holding dozens of rhesus monkeys, who played, ate, groomed, fought, and above all, screamed.

It measures my own ignorance, I know today, that the sight terrified and dismayed me. I didn’t realize that this is how monkeys act normally, and that the communal enclosure, which allowed them to socialize and interact as they would have in nature, actually represented the pinnacle of humane digs for these cantankerous but brilliant near-relatives of ours [1].

Monkeys are just loud, is all.

I can’t, however, repudiate my feelings as I walked back out, mulling my interview with the addiction researcher I’d come to cover. I remember being struck by the immediate relevance of this person’s work to human addiction, and thinking that this research could very well provide a breakthrough to alleviate the vast human suffering that drug addiction causes.

I also remember thinking that I wouldn’t want a daughter or son of mine to marry someone who could do what that person had done to those monkeys.

Let me give a quote that encapsulates where I’m coming from:

The value of animal experimentation to human health and knowledge is not seriously in doubt. But past “scientific” beliefs — such as that animals cannot feel pain; that an animal rendered motionless by anesthesia cannot feel pain; and that higher animals such as dogs and primates cannot feel anxiety and fear — have been overturned by increased scientific understanding.

That’s from “Vivisection,” Gale Encyclopedia of Science, Third Edition, and I’m the guy who wrote it. I’d remembered adding something to the effect that, in view of the stunning misapprehensions of the past, we should regard our views today on what constitutes humane treatment of animals with humility; but it’s not in the final version. I may well have cut it myself, in editing the piece down to the specified length. But I wish I’d included it now, because it’s an important corollary.

Both my visit to the primate research center and that encyclopedia article came back to me when I encountered a real gob-stopper of a report from 1967. Unfortunately the PubMed entry doesn’t include an abstract, so here’s my summary of what they did: They took a group of people who had been hospitalized for alcoholism and, to help them kick the habit, exposed them to alcohol in coordination with an intravenous dose of succinylcholine chloride. The effect of that injection, from the original:

It was possible to obtain apnea within seconds of the patient having tasted the beverage. When apnea occurred, the patient was ventilated with a breathing bag. After breathing was restored the patient was asked to get up and dress.

A couple of important details: These guys didn’t invent the method, and were neither the first nor the last to report on it. And clearly, alcoholism had profoundly harmed the experimental subjects before the study:

The criteria used in making a diagnosis of alcoholism included a drinking pattern which consistently interfered with some important aspect of the patient’s life; that is, personal health, family life, occupation or social adjustment.

Keeping in mind these guys had entered a psychiatric hospital for alcoholism (in the 1960s — the cocktail party era), I think we can assume their alcoholism was severe. And amazingly, after undergoing what was in effect a near-death experience, these guys actually referred friends with alcoholism to the study. So we can’t argue any profound lack of informed consent, at least after the fact.

But if you’re thinking of A Clockwork Orange and the (barely) fictional Ludovico technique, you’ve got me for company: Alex, too, volunteered for the surreally brutal conditioning to wean him from the joys of committing murder, rape, and general mayhem. Waterboarding also comes to mind, and all the hairy political context that comes with it [2].

Nor was this the only eyebrow-raising item in the paper: The researchers measured the patients’ abstinence and general progress using a post-study questionnaire. Normally I’d be leery of trusting folks’ self-reporting on abstinence, but in this case the researchers confirmed its accuracy by sending the questionnaire to people who knew the subjects well and could confirm whether they were telling the truth.

This would be profoundly out of bounds today, by my understanding of modern psychiatric practice. I suppose it’s possible that you could write a release form that allowed patients to sign away their confidentiality rights in this way; but I can’t help but think you couldn’t get an institutional review board to approve it, on that basis alone.

The effectiveness the method displayed in this single paper, by the way, was quite murky — amazingly enough, control subjects who didn’t receive the drug did statistically no differently than those who did. The folks who got the drug did do better than two other control groups: patients at one of the hospitals involved who did or did not comply with then-standard psychoanalytic alcoholism treatment [3]. I haven’t tracked down the later reports on this method, which may or may not have confirmed whether it works in keeping people away from alcohol; I’ve certainly never heard of anything like this being used nowadays. But is efficacy beside the point, when the means are so extreme?

I just don’t know. And I’m painfully aware that, in the context of the suffering caused by addiction, I may not have the moral standing to make the call. I’m more comfortable with my position on waterboarding, since intelligence professionals have recently begun questioning whether it’s really been all that useful, even in the very few contexts that its supporters like to raise, which pretty much was my suspicion all along [4]. In the case of today’s paper, though, the guys undergoing the nastiness were also its beneficiaries: And it bears repeating, many of them recommended the study to their friends afterward.

But I wouldn’t want my son or daughter to marry anybody who could do this to a human being.

[1] As an admittedly unscientific observation, a friend who served as a Special Forces sniper in Central America in the 1980s reports that similar monkeys were singularly smart at stealing packs, which they rummaged for food. And as they recognized and remembered individual humans, “God help you if you killed one of them,” he added. I didn’t ask him to elaborate; “nature bats last,” as they say.
[2] Though, my God: When did the appropriate context of torture become grist for political debate?
[3] Actually the researchers pointed out that their
experimental patients were statistically better off than these “standard treatment” patients, but their control patients were not. I’m not sure whether they meant to imply a kind of statistical property of transitivity there, but it’s a dubious argument. Since they admit having used parametric statistics on non-normal data, I’m even less certain that they demonstrated anything at all.
[4] Again, a friend whose past includes a stint as a military intelligence officer in the 1980s confirmed his contempt for the post-9/11 changes in interrogation technique. I’ve absolutely no respect for the feckless argument that waterboarding isn’t torture; I have more regard for those who say, “Yes, but ...” To my mind, it was never about what we (and our allies) did to a very small number of pretty-much-100-percent-known terrorists — the roughly half-dozen “high value detainees” — as much as the hundreds of guys that the method’s defenders don’t bring up, because both their guilt and the value of what they could possibly tell us, tortured or not,
seems to be less-than-well established, to be generous. I’m not proud of saying this, but if the issue were what we were doing with a few top al Qaeda leaders, we wouldn’t have had to build a prison and it probably never would have reached public knowledge.

Monday, December 8, 2008

Tasty Wheat

Mouse: Do you know what it really reminds me of? Tasty Wheat. Did you ever eat Tasty Wheat?
Switch: No, but technically, neither did you.
Mouse: That’s exactly my point. Exactly! Because you have to wonder: How do the machines know what Tasty Wheat tasted like? Maybe they got it wrong. Maybe what I think Tasty Wheat tasted like actually tasted like oatmeal, or tuna fish! That makes you wonder about a lot of things. You take chicken, for example: Maybe they couldn’t figure out what to make chicken taste like — which is why chicken tastes like everything.
The Matrix, 1999

It comes off as inane commentary, the kind of maddening banter you get whenever people are confined together by duty, incarceration, or happenstance (and which may be one reason military rifles almost always have safety switches). But in fact the doomed Mouse’s immortal lines touch on a classic question that has long plagued philosophers.

How do I know that your experience of a thing is anything like mine?

Well, olfaction scientists have an answer to the Tasty Wheat Conundrum, and — talk about maddening — the answer is, “It depends.”

I’ve gotten ahead of myself again. Let’s start, as we often do, with Buck & Axel’s Nobel-winning work on the genes that produce the olfactory receptor proteins. Conceptually, the sense of smell starts out with a simple step: Vertebrates can identify many thousands of smelly chemicals in the air because they make around a thousand different versions of the protein sensor that sits on olfactory neurons. One odorant (or a small family of odorants) tweaks one type of receptor, which in turn is present on only one family of olfactory neurons. When those neurons fire, the brain knows that, say, acetic acid (basically, distilled vinegar) is in the air.

It’s a little more complicated than that: Actually one molecule can have several parts that activate different odorant receptors. But the pattern of olfactory neurons set in a tizzy by a single odorant molecule will be constant, and unique to that molecule.

So far so good: If everybody has the same receptor(s) for the aroma of Tasty Wheat, then at that level at least everybody is tasting the same thing (smell accounts for most of the variety of “flavors” we experience).

The next step in the sense of smell is when the olfactory neurons in the nose tweak the olfactory bulb in the brain. The OB is the central routing station for all smells; it coordinates the signals coming in from the nose, and may in addition enhance those signals — for example, as a powerful amplifying system for detecting faint odors.

Every olfactory neuron with the same receptor reports to the same glomerulus — a little ball of relay neurons that sends the signal up to the higher brain — in the OB, and each glomerulus gets signals from only one type of olfactory neuron. They map perfectly, one-to-one.

This is where things get messy, and a new report by Kimberly Grossman and colleagues at my wire-mommy Alma Mater, the University of Chicago, doesn’t make it any cleaner. But it does raise some interesting questions.

What the Chicago Five did was use sophisticated imaging of glomerular activity in concert with some old-fashioned mousie-chooses behavioral experiments (thanks, I’m guessing, in part to collaborator Leslie Kay, an extremely interesting lady who I’ve written about in the U of C Magazine) to compare what a mouse was doing to what its brain was doing.

One question they wanted to answer was whether a behavioral pattern in odor perception called a configural percept exists at the neural level. A configural percept is what happens when a mixture of chemicals that smell similar to each other add up to a completely different smell. Its opposite is an elemental percept, in which different-smelling odorants retain their individual smells when mixed together.

We know these phenomena exist at some level, because humans report them and mice act as if they experience them, too. But when Grossman and her homeys compared simple mixtures of two smelly molecules — pentanal and hexanal (two very similar odorants that arise from hamster litter, and which contribute to the smell of old rice) — elemental percepts depended on the exact mixture, and configural percepts were nowhere to be found. Worse, what was happening in the OB didn’t seem to bear much relationship to how the animals were reacting.

When they tested Mickey’s and Minnie’s ability to recognize the components of a mixture after being trained to spot the mixture, that ability depended on the ratio of the two components. With ratios of pentanal to hexanal smell that were equal to higher-on-the-pentanal-side, the response was purely elemental. Despite the fact that the two odorants were similar, animals trained on these mixtures were able to recognize either component on its own, no problem.

When hexanal smell outweighed pentanal, though, something very different happened: It was as if the mixture no longer contained pentanal, all the mice could smell was the hexanal. This overshadowing percept wasn’t expected.

Things got even loosier-goosier when they looked at the animals’ brains. The pattern of the glomerular activity of the olfactory bulb paralleled the behavior for the elemental percepts -- the pattern of glomeruli activated by the mixture looked pretty much like adding together the glomeruli activated by each separately. But the glomeruli for poor ol’ overshadowed pentanal were firing like crazy even when its smell was in the minority — and when the mice were acting like they couldn’t smell it.

We already suspected that the higher brain mucks up perception of smells — Proust’s over-cited cookie fetish works both ways, odors don’t only trigger powerful memories, memories exert powerful influence on how we experience odors. What this report shows is that there’s even a gap between the brain’s first processing step and what comes afterward. That gap may yet contain a one-to-one translation of chemistry to perception, but it doesn’t seem all that likely.

So let’s split the difference: At the level of hardware we share with snails and insects, my Tasty Wheat tastes like your Tasty Wheat. But once we move beyond the level of brain structures we share with lizards or fish, maybe my Tasty Wheat is your tuna fish.

Think on that over your morning cereal. But try not to irritate your cellmates.

Tuesday, December 2, 2008

What the ...

The scene: Somewhere in Pennsylvania.

The venue: a local politician’s annual meeting with local emergency responders. Intention is to give us a pat on the back, let us listen to some interesting talks by members of our community, and generally give us the elected official’s ear for an evening.

What we were not expecting, at this gathering of largely middle-aged, white-male cops, firefighters, and EMTs, was the opening act: An interpretive dance by a young man and a young woman, to the tune of "Yankee Doodle Dandy," involving lots of saluting, leaping, and tights. Yes, tights.

Look: I don’t want to come across as some kind of Philistine here [1]. And I’m not foolish enough to think that dancers are sissies — we had one join our kendo club in Boston, back in the Before Time, and I can tell you that, within a month, he was kicking our asses with monotonous regularity. But for this audience, in this venue, it was a colossal mismatch.

We middle-aged white males have come along some, as you may have guessed from the recent election. The audience offered polite — maybe even more-than-just-polite — applause at the end. But you could also see the clockwork whirring in all the balding heads, and it went kind of like this:

What in bleeding heck was it that I just saw???

Sometimes science is like that; a new fact pops into view, and its incongruity is so striking that you literally don’t know what to do with it. But it bugs you enough that you just have to try to make sense of it.

Enter a report by Carl Philpott and crew at the universities of Leicester (I’m guessing pronounced "Lester") and East Anglia back in the Empire. This is a preliminary report of an accidental finding of superosmia — the ability to smell an odor at literally superhuman sensitivity — among a stunning 4 percent of 230 healthy subjects.

First, the background: Philpott and his colleagues were carrying out a new protocol for measuring human sensitivity, using two specific odor-carrying molecules: phenylethyl alcohol (a rose-like floral scent) and eucalyptol (three guesses). To their surprise, they found that 2 percent of healthy volunteers recruited in a hospital waiting room demonstrated sensitivity about a thousand times normal to one of the odorants when exposed to it once. When they gave another group of volunteers 10 or more trials apiece, the per-person frequency of super-smelling in at least one of the trials was a gob-stopping 10 percent. The two averaged out to just under 4 percent of all the subjects tested. Even freakier: these super-smellers sooner or later experienced a rapid loss of this hypersensitivity.

What gives? Honestly, I have no idea, and Philpott & Co. aren’t sure either. The researchers really didn’t find anything compelling on this in the past literature — the closest, a 1994 report by Amoore, even Amoore himself apparently thought was an artifact [2]. We’re all aware of the fact that many women become hypersensitive to odors during pregnancy — but the evidence suggests that’s because of a stronger reaction to odors at a "normal" level of sensitivity, not a true enhanced chemical sensitivity.

Hovering over the whole business: this is a new testing method; they might find something squirrelly about how some people test with this methodology that isn’t a bona fide sensitivity.

What biological function a random, temporary burst in sensitivity to a single odorant might have is what’s bugging me. We could be seeing something conceptually like the immune system’s random generation of antibodies with the idea that some of them will be useful for fighting infections. It’s a stretch, but it’s all I can think of.

The investigators did throw out one very neat idea for a mechanism, though. They suggested that superosmia might be “enabled by stimulation of an alternative olfactory pathway, such as the vomeronasal organ.”

Let me contextualize that a bit: The VNO is the suspected receptor organ for pheromones — airborne hormones that members of a species use to affect each others’ hormonal status, for mating, social dominance, or whatever. Its most interesting facet in this context, though, is that the receptor proteins that the VNO uses to sense pheromones are far more specific, and because of that, bind odorants far more tightly, than the olfactory receptors in the nose that detect run-of-the-mill odors.

Care to guess how much more tightly? That’s a tricky one, because the different chemical properties of olfactory (volatile) and VNO (often non-volatile) odorants make for an apples-oranges comparison. But if you guessed a thousand times — roughly the same factor as the superosmia — you’d be in the neighborhood of an admittedly crude, and maybe off-base, comparison.

In reply to some questions I emailed him, Philpott happened to mention that an earlier version of the paper, with more thoughts along these lines, ran into trouble with the reviewers. But he says that in follow-up experiments they’ll give a particularly close look to the idea that the mechanism for superosmia is the unmasking of a pheromone receptor in the human nose (which we already suspected existed).

So that’s the deal. I’m still trying to make sense of it; it feels like it ought to be important. But I still have no idea what it was I just saw. But I’m looking forward for the bigger picture to jete into view.

[1] A remarkably cultured and urbane people, the Philistines. But they picked on the wrong dudes, at least for their long-term PR.
[2] Sorry, no abstract on Oxford University Press or Google Scholar. But if you want to look up hardcopy, it’s Amoore J (1994) Chemical Senses 19:434.