Jonathan Dobres

I’m taking a class about professional issues in psychological science, in other words, a class in how to be a real scientist. Giving talks is as much a part of the professional life of a scientist as running a lab and applying for grants, so yesterday was talk day. The goal was to give a talk about your research lasting no more than ten minutes, and I hit it on the dot. The talk was generally well-received, which was gratifying, as it will likely evolve into my eventual dissertation defense. Then the professor spoke. “Really great job,” she said, “but, Jon, why should I care about this topic?”

Ah yes. That. I knew I had forgotten something. To be fair, I’m not likely to give this talk to audiences who are utterly unfamiliar with the topic in question, which in this case is something called perceptual learning. But I’m hedging here. I can play devil’s advocate with myself until the sun implodes, but really, I should have just found an extra thirty seconds to explain why my field matters. Good scientists explain their work clearly and concisely. Great scientists—your Carl Sagans, Oliver Sackses, Steven Pinkers, and Albert Einsteins—make the point of their work so obvious and accessible that anyone can understand it.

To the above list of Great Scientific Communicators we should certainly add Dr. Jean Berko Gleason. Dr. Gleason is one of the world’s preeminent psycholinguists, and if you don’t know what a psycholinguist is, I’ll let her explain. All those clips are wonderful (and yes, she is exactly like that in person), particularly for how clearly she explains herself. Multiple branches of nuanced research laid out—zip, boom, bonjour—in half a minute. After watching those clips no one is left wondering why psycholinguistics is an important field. We all understand why Dr. Gleason has allowed psycholinguistics to fill her life, and how it’s relevant in our own.

So what about my field? What’s perceptual learning?

Perceptual learning is a process by which we get better at perceiving things over time. We’re not interested in changes in strategy or decision making (usually), rather, true perceptual learning means that you are literally getting better at seeing. With practice, you can become more sensitive to contrast, motion, or a thousand other things. Take my dentist, for example. Since I’m a graduate student with a bargain basement dental plan, my dental work is performed by fourth and fifth year students at my university’s dental school. Before the end of every visit, a supervising dentist double-checks the student’s work. During one recent checkup, my student dentist told his supervisor that he hadn’t found any cavities in my mouth. The supervisor took one of her tiny metal hooks in hand and glanced it over my molar for what could not have been more than a second. “There’s some decay there. We’ll need to schedule a follow-up to treat it.” She, the experienced dentist, had seen plainly what the less experienced student could not, because her extensive training had made her more sensitive to the tiny precursor of a cavity on my tooth.

It’s not just dentists, of course. Radiologists have to hunt through murky x-rays to find fractured bones and dangerous tumors. Baggage screeners need to be able to spot a knife amongst shampoo and sweaters. Jewelers peer inside diamonds, looking for perfection. Perceptual learning makes the difference between an amateur and an expert.

Perceptual learning is important because it demonstrates that experience and practice can create dramatic change in the brain. If you have a stroke, can we help you recover? Yes. As the developed world grows older on average, what can we do to protect the brain from the ravages of age? Back in ‘86, two researchers showed that you could turn an eighty year old into a twenty year old, given enough practice. We spend increasingly large amounts of time playing video games. Some decry this as a waste of time, a habit fated to create a nation of ADHD-addled zombies. But the science says video games improve our visual capacities. Hell, what are you doing right now? How did you get so good at reading? How are you able to process letters, words, and whole sentences with such blinding speed? In part, reading is a product of perceptual learning.

Over the summer, I participated in a colleague’s experiment, one that involved what’s called a texture discrimination task. Imagine a grid of horizontally dashed lines. Somewhere in the grid, off in your peripheral vision, three of the dashed lines have been turned into diagonal slashes. Sometimes the slashes are arranged vertically in the grid, and sometimes horizontally. The whole stimulus is displayed for a fraction of a second, and your job is to say whether the slashes were vertical or horizontal. On the first day of the experiment, the task was impossible. My performance was so poor that I might as well have had my eyes closed. It was the same story on the second day. After three weeks of training, however, my performance bordered on perfect. The exciting thing, the amazing thing, was that I could feel my perception changing over time. What had once been impossible became trivially easy. The slashes, once as jumbled and fleeting as a snowflake in a blizzard, now jumped out at me as clearly as a snowball in summer.

As scientists we can argue at length about why and how my perception changed. Was it a low-level change in highly specific sets of neurons, or was it a broader change in the way I allocate attention? Will this transfer to other tasks, and what does that mean? Was I detecting the slashes, or filtering out the horizontal lines? It’s easy to get bogged down in the methodology and specifics, and lose sight (har har) of the big picture. Whatever the reasons, there is no doubt in my mind that my perception changed over those three weeks, simply as a result of diligent practice. That’s an amazing thing, a powerful thing. That’s why I do what I do.

Every Psychology 101 course will spend a week or two on the principles of learning. The larger question being addressed is: How can a person’s thoughts or behaviors be changed in an enduring way? In discussing how this question has been studied by psychologists, the lesson invariably starts with the example of Pavlov’s famous drooling dogs and ends with B. F. Skinner and his quirky pigeons. How quirky were they, you ask? Skinner successfully trained his birds to play ping-pong, and even secured military funding to see if he could train them to act as bomb guidance systems. Project Pigeon, as it was called, actually worked, to an extent. True story.

Students don’t have much trouble with the drooling dogs and bombardiering birds. Nor do they have much difficulty mastering the concepts of positive reinforcement, in which you are given something desirable (food, money, etc)to reinforce a target behavior, and punishment, in which you experience something unpleasant whenever you perform an undesired behavior. Confusion doesn’t set in until_negative_ reinforcement is brought up. Negative reinforcement, just like positive reinforcement, increases the likelihood that a target behavior will occur (in contrast, punishment decreases the likelihood of a behavior occurring, and isn’t very good at creating long-term behavior change). The difference is that while positive reinforcement introduces something pleasant to reinforce behavior, negative reinforcement works by removing something unpleasant.It’s a tricky concept to teach because it’s difficult to think of examples in which you’re removing something unpleasant without also introducing something pleasant. As it happens, I’m living just such an example right now.

I am not a morning person. I never have been, and I probably never will be. I am not one for whom the dawn is its own reward. It takes a supreme effort and an elaborate system of alarms to wrench myself out of bed every morning. During holidays my circadian rhythms inevitably slide toward the nocturnal. I eventually find myself falling asleep at 4:00AM and waking up at the crack of noon. Nevertheless, I can count on one hand the number of times I’ve overslept for an early appointment. If I absolutely have to be somewhere at 7:00AM, I’ll be there. It’s just how I was raised.

For the past two weeks I’ve been arriving at the lab by 7:30AM. Initially I did this because I had to; a subject in an experiment I’m running could only come in at 8:00AM. But the subject in question finished up last week, and now I’m coming in early by choice. You may be wondering how I’ve managed to sustain such a miraculous change in my behavior, and believe me, “miraculous” is definitely the word here.

It has everything to do with the B Line. Anyone who lives in Boston knows what I’m talking about. The B Line is by far the slowest, most crowded, and least reliable subway line in the city. That it serves the most densely residential sections of the city but runs the fewest trains is a topic for another day. The end result is that rush hour on the B Line is a nightmare. Moreover, the B Line remains crowded for huge swathes of the day, even as the ridership on other branches of the Green Line thins to almost nothing. The thought of having to stuff myself into a B Line car for what is, all things considered, a short commute fills me with dread.

It turns out that if I can get myself onto the train by, say, 7:00AM, all of these problems go away. The trains haven’t had the chance to get backed up, seating is plentiful, and the ride is quantifiably faster. The whole experience is far less aversive, so much so that I’m actually willing to push against twenty-seven years of night owl habits to change my behavior. Negative reinforcement in action, ladies and gentlemen.

There are positive reinforcers as well, of course. There are more hours in my day and I’m more productive (the only other time in my life where I managed to maintain this schedule also happens to be the time I wrote daily). Since I’m in so early, I don’t feel bad about dodging the evening rush hour by leaving at 4:00. The positive reinforcers are obvious, but it’s the negative reinforcement of avoiding a horrible commute that gets me up in the morning. Skinner tends to get a bad rap these days, but there’s no denying that the man was on to something.

Imagine that it’s 1939 and your country is about to enter World War II. Further imagine that you work for your country’s government, and you have been charged with designing a series of posters with the goal of calming the public in the event of mounting catastrophe. Also, you are British. Immersed in such a situation and thrown a dash of inspiration, you might—I say again, might—come up with something half as brilliant as what was actually designed for this purpose: “Keep Calm and Carry On”.

“Keep Calm” was the final poster in a series of three commissioned by the Ministry of Information. It was intended to be used only if Britain was invaded by the Germans. I mean, really, how stiff upper lip can you get? There you are knee-deep in Nazis and the King’s message to you is simply, “Keep calm and carry on.” Of course, Britain was never invaded and this third poster never saw the light of day (though one supposes that this might have been an ideal message during the Blitz). The poster was forgotten by history until 2000, when an errant copy turned up at Barter Books of Northumberland.

The bold color, stark typography, minimalistic Crown symbol, and wonderfully succinct slogan combined to create something that was both emblematic of the era and perfectly British, all in little more than five words. Suddenly I remembered that the Southerner’s birthday had just passed (don’t look at me like that, he’s not big on presents) and that he has an affection for all things Royal. It became clear that I had no choice but to buy him a copy for his own especial privilege and certain knowledge.¹

Here’s where things get tricky. Crown Copyright on “Keep Calm and Carry On” expired more than twenty years ago. Combined with the poster’s simple design and immense popularity,² this means that there are a lot of knock-offs floating around the internet. All of them feature the Crown, but only some of them use an accurate font. Since the poster is almost all text, the accuracy of the typeface is critical. Barter Books claims to have the original poster. I have no reason to disbelieve them, but some of their merchandise uses a font that is obviously different from the original’s (note the way the letter “C” terminates, as well as differences in the “M”). The match is close, but not close enough, which is deeply confusing. KeepCalmAndCarryOn.com (even more rhyming than the original!) seems to employ the same near-miss typeface, except on the book (weird, right?). Don’t even get me started on the cheap and highly inaccurate reproductions available on Amazon, which appear to use Adobe’s Myriad Pro. While Myriad has the benefit of being free, it looks nothing like the original 1939 letterforms (particularly noticeable on the letters “K”, “C”, and “M”).

So, Mr. Amateur Typographer, you might be thinking, what’s the correct typeface, then? The answer, I think, is that it doesn’t exist. Given the way that posters were produced in 1939 and the limited set of letters that “Keep Calm” employs, it’s more likely that the text was drawn by hand specifically for the job. This means that the only accurate type sample is on the original poster itself. I found one vender on eBay who had gorgeous, accurate prints for sale, but because I live in a disreputable neighborhood the print went missing somewhere between the confirmed delivery and my arriving home. Luckily enough, Wikipedia’s version of the poster appears to be a direct copy of the original, and even better, it’s in SVG format. This means that provided you have a suitable vector graphics application and a decent print shop, you can make your own crisp, typographically accurate copy in any color or size you like. As it happens, I have both, so today I’ll be able to present the Southerner with his long-overdue birthday gift. 24x36 inches big, violently red, and defiantly British.

A few years ago I had to go to the RMV to get my driver’s license renewed. This involved, aside from the paperwork and general atmosphere of human degradation, a quick eye exam. In Boston this is done by peering into what looks like a table-mounted View Master, only instead of slides of the Superfriends, this one has an eye chart.

“Read the letters above the green line, please.”

“X-O-Q-T,” I say. This is followed by a slightly too-long pause.

“And the rest of the line, sir?”

“Oh,” I say, quickly recognizing the problem. I need to turn on my right eye. I squint my left eye shut to give my right eye a jumpstart, and the rest of the line pops into existence. “R-P-V-M.”

Without another word she moves on to the rest of the paperwork. I didn’t get my license renewed that day, but that’s a different story. The point of my telling you this is to let you know that like many people born with cerebral palsy, I have a lazy eye. Or rather, I had a lazy eye, surgically corrected when I was about two years old. As with language, where there’s a sensitive period during which the brain can soak up a native language with ease, there’s a similar period for the wiring of depth-sensitive neurons. This period occurs at a very early time in development, so my depth-sensitive neurons didn’t develop in an ideal manner.

I’ve spent most of my life with this crippling visual disability. Unable to play catch or aim a frisbee. Terrible at estimating how far away I am from anything. And most damningly, utterly unable to shake hands or open doors without accidentally punching someone in the mouth or mashing my fingers against the wall. My hands, they ache from being bitten and bludgeoned so.

Or, you know. Definitely not.

This is why articles like “How 3D Works (And Why It’s Back!)”, by Erez Ben-Ari, never fail to tick me off. They inevitably equate depth perception with stereopsis (literally “solid sight”), a phenomenon experienced when the two slightly different images hitting your eyes merge to produce a sensation of depth (this process is also called binocular fusion¹). In reality, stereopsis is a minor contributor to depth perception, most useful within a range of five feet and essentially useless beyond twenty. The lion’s share of depth perception arises from monocular (one-eyed) cues. We tend to take these for granted since they seem so basic: the way solid objects overlap each other, the way things get smaller as they get farther away, changes in texture and other visible details, to say nothing of a little thing called motion, which always seems to get neglected in discussions of depth perception, academic or otherwise.

Mr. Ben-Ari’s article makes a mistake pretty early on when he claims that “3D imagery has been around for ages, mostly as a gimmick, but things have changed in the past few years.”

Well, sort of. Stereoscopy, or the process of creating a sensation of depth from a pair of 2D images, has been around since 1840. Sir Charles Wheatstone invented the first stereoscope (among a few dozen other things). In fact, Wheatstone’s stereoscope is still used in vision research today, as the apparatus is both cheap and easily adjustable for each observer. You can make one yourself, either with mirrors and cardboard or, if you’re feeling particularly American, with iPods. Even setting the research applications of stereoscopy aside, Ben-Ari’s claim that it’s mostly a “gimmick” is debatable. Any doctor who’s ever gazed into a professional-grade microscope will tell you how useful that extra depth cue can be. Of course, research into stereopsis eventually led Béla Julesz to the random dot stereogram, which in turn gave us the Magic Eye. That’s not just a gimmick, that’s torture. There is no Easter Bunny.

Ben-Ari can also be faulted for failing to do some basic research into the history of 3D movies. Discussing the various methods of projecting 3D movies he says, “…the most popular way, initially, was to use the notorious red-blue glasses…A few years ago, a new delivery method came about, based on polarizer glasses.”

Ben-Ari gives the impression that this polarization technique is all newfangled, arriving on the scene “a few years ago.” I suppose that’s true, if by “a few years,” you mean seventy-four. Polarized 3D movies were patented and marketed by the brilliant Edwin H. Land in 1936. In fact, he started a little Mom and Pop business called Polaroid, perhaps you’ve heard of it? Most of the 3D films shown during the “golden era” of 3D in the 1950s were projected using the polarized method, with the more well-remembered red-blue lens system being used for comic books and later TV adaptations.

All this is window dressing that hides Ben-Ari’s real whopper. After a discussion of the basics of binocular depth perception and before his inaccurate recounting of the history of 3D film, he casually says, “For this reason, people with a damaged eye cannot judge distances correctly.”

Oh, I beg to differ. So would cinematographers, surveyors, and snipers (and anyone who spends a lot of timing estimating distances with one eye shut, really), as well as Bryan Berad, the one-eyed professional hockey player. While we’re on the subject of sports, I found at least three Major League pitchers who are blind in one eye: Thomas Sunkel, who pitched for the Cardinals, the wonderfully named Whammy Douglas, who pitched for the Pirates, and Abe Alvarez, who pitched a few games for the Boston Red Sox during—get ready for it—the 2004 season.People with damaged eyes should be concerned more with their diminished field of view than anything else. Judging distances is not a problem.

Let it also be known that not all “damaged eyes” are equal. If you’re like me and you have some form of amblyopia then not all is lost. Evidence suggests that special visual exercises can restore an amblyope’s visual function to normal levels. At a large vision conference last year, I had the pleasure of meeting Dr. Sue Barry, who showed me that I can even restore my stereopsis, provided I’m looking at the right things. My recent experiences at 3D movies like Up and Coraline have shown me that I am indeed capable of perceiving stereoscopic effects, which suggests that with training I might be able to fully restore my 3D vision.²

So let’s review. Erez Ben-Ari wrote an article on the resurgence of 3D movies in which he botches the science, rewrites history, and fundamentally misunderstands why this resurgence is taking place. It’s not really about improved stereoscopic technology (although it’s certainly easier today than it was in 1936, when two reels of film had to be meticulously synchronized to prevent the audience from dying of eye strain). It’s more about 3D as an attraction. You still can’t get good 3D in your home, which means that the theater is the place to be. For this reason, I doubt we’ll ever see a usable home solution for full-color 3D. If the movie industry hasn’t already gummed up the works on that project, they really should. It’s where the money is. Just look at Avatar.

As games go, Tetris is hard to improve upon. Things like head-to-head play, “obstacle” Tetris, and 3D variations increase the novelty of the experience, but rarely make for a better game than the original 80s action puzzler. I had yet to see a modification of the original formula that actually makes for a better game, until now. Not only is this a pixel-perfect recreation of the classic Nintendo version, but it comes with a simple, brilliant twist that will make you laugh out loud, tear your hair out, and keep you coming back for more. I played Tetris—this exact version of it, no less—for hundreds of hours, and yet with this one simple change, the entire experience is fresh again. That’s quite an accomplishment.

From a recent article on video games, written by Charlie Brooker:

If you’re a gamer, you’ll naturally want others to share the experience. So you try to introduce the game to your flatmate, your girlfriend, your boyfriend. But they’re wary and intimidated. From their perspective, even the joypad is daunting. To you it’s as warm and familiar as a third hand. To them it’s the control panel for an alien helicopter.

But you persevere, press the pad into their unenthusiastic hands, and offer to talk them through a few minutes of play. And almost immediately you have to bite your tongue to avoid screaming. They run into walls or hit pause by mistake. They swing the camera around until they can see nothing but their own feet, then forward-roll under a lorry. They try to put the controller down, complaining that they’re “no good at this”. You force them to have another go, but within minutes you’re behaving like a bad backseat driver.

What’s funny is that not one week before I read this article, I had exactly this experience with Damian, he of the fine photography and frequent website comments. He was visiting Boston for New Year’s, and in one of our quieter hours I suggested he try out the demo for God of War III, which amounts to roughly fifteen minutes of truly exquisite violence. “I’ve never really played video games,” he said, by which I thought he meant, “I rarely play them, they are not my thing.” What he really meant was, “No, seriously, I’ve never played a video game. Certainly not one of these 3D ones.”¹

Apparently his mother had forbidden him from playing such games as a kid, which strikes me as odd, as Damian routinely describes his mother as a garden variety California hippie, and not the sort of person I would imagine prohibiting a Playstation in the house. Well, you’re on the East Coast now, buddy, where the only rule is, there are no rules. Except that in Boston you can’t ride the subway after 12:30AM and in New Jersey you can’t make a left turn on a highway. Other than that, no rules.

Ever the good sport, Damian starts the demo and commences the surprisingly fun process of murdering several dozen faceless minions. The demo walks him through the basic controls as he plays. So far so good. Then we come to the Harpy Ride section. “Press L2 and Square to fire your bow,” says the game. Damian does so, thus attracting the attention of a nearby flying harpy the subtle way, by puncturing it with flaming arrows. As the harpy draws near, the game commands, “Press L1 and Circle to ride the harpy.” Again, Damian complies, and finds himself attached to the harpy as it flies across a small chasm, towards a second harpy he’ll have to commandeer if he wants to finish the crossing.

Here’s where we run into trouble. The game makes it simple to jump from one harpy to the other. As the player gets within range of the second harpy, the harpy is highlighted in a blue light. Press X, and the player will simply jump onto the highlighted harpy. The thing is, the second harpy never lights up. Damian seems to get close to it each time, and maybe it flashes blue for a split second, but never long enough for him to press X and grab on. This section of the demo takes a little getting used to, and most people mess it up once or twice. But six times? Seven? Troubling.

Finally, I see the problem. God of War uses a fixed-camera system, allowing the game designers to present each section of the game as beautifully and cinematically as possible. During this particular section the camera is at a 30-45° angle to the action. Instead of moving in a straight line over the chasm, Damian is veering sharply to the right.

“You’re moving him off to the right. You need to move him more forward.”

“I am.” Welcome to the joys of backseat video gaming, by the way.

“No you’re not. Move him away from the camera.”

“And which direction is that, Jon?”

“You know, forwards…away…in. Move him into the screen.”

At this point I get up and move myself behind Damian so that I can look at the controller. I look at the control stick and imagine myself playing this section of the demo. “Up and just a bit left.”

And just like that, he was across.

I find it downright fascinating that Damian had a problem here, because for any experienced gamer there is simply no problem to be had. The game tells me to move, and I just know how to do that. The fact that I’m using a 2D control stick to move in 3D space doesn’t even register, because I first learned how to do this kind of spatial conversion, what, fifteen years ago? I don’t even know which game might have been responsible for rewiring that part of my brain. Final Fantasy VII? Battle Arena Toshinden? Super Mario RPG? Q*bert? God only knows.

The point is, this sort of spatial mapping is an acquired skill, one I learned entirely through video games. It’s easy to think of more specific examples. Are there four unlit torches in an otherwise empty room? Is this a Zelda game? Well then, let me go get my matches. I once played Zelda: The Wind Waker as my brother, nine years younger than me, observed the action. I was visiting home from college, and this was thoroughly His Game. I walked into the dungeon, saw the unlit torches, and, without a second thought, proceeded to light them. “How did you know how to do that,” he asked, confident that his older brother would’ve gotten stuck on this puzzle, crying out for assistance. I said, “I have been lighting these torches since before you were born.”

Light the torches. Move the stick up and to the left to go in. Who says video games can’t teach you anything?