So Many Itches To Scratch

The sometimes-innovative power of things that can be scratched, one of our lesser-appreciated forms of physical interaction.

By Ernie Smith

Today in Tedium: It may be weird to consider in a world where we have so many ways to interact with things through touch, but we don’t use all of those types of interaction to communicate with a computer. To offer an example: Scratching. Often done with fingernails, quarters, or other somewhat abrasive materials, it’s a common type of gesture that has no true equivalent in the world of smart devices (well, unless you scratch your screen). I’ve been thinking a lot about the nature of scratching recently, and for today’s Tedium, I wanted to offer up every single scrap of thinking on scratching. I’m feelin’ kinda itchy. — Ernie @ Tedium

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The year that Friedrich Mohs, a German geologist, came up with the Mohs scale of mineral hardness, an approach that helps researchers determine how resistant to scratching various materials are. This long-in-use tool, kits for which can be purchased on Amazon has gained a modern use case for some—the popular tech YouTuber JerryRigEverything frequently uses it to test the resistance to scratching that smartphones have.

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(Erica Feliciano/Flickr)

Scratch-off lottery tickets: The guy who invented them is doing something kind of ironic today

There have been a lot of innovations involving scratching over the years, but none has perhaps reached the same level of cultural cachet as the scratch-off lottery ticket.

Thanks to its use of a latex-based ink or varnish that covers up the winning details until you scratch them off, scratch-offs are naturally multi-layered, and that general design allows for things to be hidden. In some ways, the coating is the key element—but in others, it’s the underlying algorithms behind the game of chance. Maybe it’s the combination of the two.

As the Detroit Free Press reported late last year, the invention comes to us from an early computer scientist named John Koza, one of the first graduates of the University of Michigan’s computer science program. Koza’s innovation was not the scratch-off material itself—which was already in wide use by his employer in undergrad at the time, the sweepstakes company J&H International—but the addition of algorithms that helped turned lottery games into things that could be played—and won—instantly, rather than things that came with a long wait.

“It offered instant gratification,” Koza told the Freep. “Now, you wouldn’t have to wait until Saturday night to see if your ticket was a winner, you could find out immediately. It was really quite obvious to us that it would work.”

Koza’s idea was a winner, but J&H was not—it went into bankruptcy in the early ’70s. Rather than let that stop the idea dead in its tracks, Koza and marketing-focused business partner Daniel Bower launched a new company, Scientific Games, to market the idea. It wasn’t easy—trying to sell instant lottery games was a complex endeavor, as the field was highly regulated—but once everything was in place, the idea took off in a big way.

Scientific Games is still around today—to give you an idea of its size, it’s the parent company of Bally Technologies, the billion-dollar slot machine maker that is directly tied to the one-time pinball machine maker.

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John R. Koza, the inventor of the scratch-off instant lottery card, and a crusader for the National Popular Vote. (Eric Slomanson/Handout photo)

Koza, however, has long past moved on—an impressive technical mind, he has taught at Stanford and is considered an expert on the subject of genetic programming. More recently, though, he’s become well-known for something completely unrelated to either computer science or lottery tickets: He is one of the key figures in National Popular Vote, a long-running campaign to make the case for working around the electoral college by getting states to pledge their votes to the leading vote-getter in a given election. Koza’s efforts there have been successful enough that slightly less than a third of all states, representing 196 of the 538 electoral college votes, have passed laws agreeing to the plan. Once the plan hits 270 electoral votes—possible as it’s seen success in many legislatures around the country—it becomes the de facto law of the land.

It’s ironic that a guy known for popularizing a game of chance is now trying to take some of the chance out of the process of voting for president, right?

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Fewer stock photos of people scratching themselves than I was expecting, so here’s a picture of a dog going at it. (Kristian Niemi/Flickr)

Five interesting facts about scratching things on the human body

  1. Scratching an itch triggers a neurological response that helps distract from the itchiness. As Harvard Medical School’s On the Brain notes, research has been done in recent years to show that scratching—which, technically, involves hurting yourself to distract from something annoying—brings deep relief that you feel all the way in your spinal cord, directly to your brain. The report also notes that it’s believed the reaction came about as a defense mechanism against flies or other insects.
  2. However, scratching an itch has an unfortunate side effect. As you might have noticed when you get a scratching fit, you often feel itchier after you’ve started scratching. Part of this is the result of serotonin, a chemical produced by nerve cells, going into overdrive. As the BBC notes, when the spinal cord responds to the serotonin, it actually intensifies the impact of the itch. “In mice, there is a vicious itching [and] scratching cycle,” noted Professor Zhou-Feng Chen, the director of Washington University’s Center for the Study of Itch. “If you reduce the serotonin the itchy intensity reduces.”
  3. Some itches are better relieved by scratching than others. Back in 2012, itch expert Gil Yosipovitch, M.D. of Wake Forest Baptist Medical Center put together research that tried to figure out where the relief from itching was most pronounced. As a part of his experiment, he induced itching in a number of research subjects in different parts of the bod, and found that itching was felt most intensely on the ankle and back, while scratching the ankle tended to offer more relief than other parts of the body during an itching fit. “We never understood why those areas were more affected, and now we better understand that itch in these areas is more intense and pleasurable to scratch,” Yosipovitch said.
  4. If you have an itchy scalp, it might be dandruff—or worse. Want to have nightmares about your scalp for a week? Check out this page from the American Academy of Dermatology, which suggests reasons people get itchy scalps. A failure to remove shampoo from your hair is one reason—along with lice. (Also, we missed this, but apparently there was a video trend in 2018 involving scratching off dandruff?)
  5. “Skin writing,” or dermatographia, is actually fairly common. Some people, when they scratch themselves, are able to draw on their skin, technically, due to the nature of the hives they get. It might sound bizarre or even painful, but it’s not considered dangerous, and is actually fairly common—around 2 to 5 percent of the population is afflicted by the condition. Not exactly one-in-a-million odds.

“Many cats will scratch, paw, or knead the ground around their food bowl before or after eating. The pawing and digging is an example of instinctive behavior, meaning your cat probably didn’t learn it from its mother.”

— Franny Syufy, a freelance writer, discussing the reasons why cats tend to paw or scratch the floor near their food bowl. It’s not because they don’t like it, according to The Spruce Pets. “It may not seem to make sense that a house cat without any threat of their food being taken would exhibit this kind of behavior,” Syufy writes. “And, it doesn’t make sense, really, except for the fact that the behavior is instinctual and cats do it naturally.”

The convenience store chain Circle K actually used Scratch N’Sniff technology as a marketing tool in the ’80s.

How does scratch and sniff paper work? The underlying innovation behind the scents

I have many memories of the 1980s and early 1990s, but one of the most enduring memories for me is seeing the 3M logo on various sizes of floppy disks. For a while, that logo was everywhere in the computer world.

But that simple use of solid red Helvetica was not the starting point for the Minnesota Mining and Manufacturing Company. As highlighted by The Logo Smith, not by a long shot. Graham Smith, a visual designer, counts 30 different logo variants for the company over a nearly century-long period, with some years seeing multiple separate redesigns. (They’ve mostly stuck with the current design since 1978.)

Likewise, 3M the company has gone through an array of evolutions over the years, selling things as diverse as dental products, Scotch Tape, Post-it Notes, and even traffic signs.

Fascinating, right? Well, on the way to basically making everything under the sun, a 3M researcher invented a key scratching innovation—scratch and sniff paper. Like many good inventions, it built off of the ideas of others. In the 1950s, National Cash Register employees Barrett K. Green and Lowell Schleicher came across a process for something called carbonless copy paper, a transfer-coating material that allows for writing on multiple forms at the same time without the use of carbon.

This was done using a process called microencapsulation, in which small particles or droplets were placed on the page, which then appeared when pressure was applied to the page, causing microcapsules to burst. While microcapsules have a variety of uses—most notably, they drive eink screens today—this was one of the most technically novel uses at the time.

NCR’s Green and Schleicher came up with the general idea (with some necessary changes due to chemicals used), but 3M came along and added its own twist to the process.

The Minnesota company’s own chemist, Gale W. Matson, implemented the microcapsules using a different material. Not content to simply let microencapsulation be used for the boring work of filling out forms, the company figured out that scented oils, rather than colors, could be included inside of microcapsules.

As Mental Floss notes, this realization, per Matson’s patent filing, gave us the process for Scratch N’Sniff paper:

A number of perfumes were encapsulated in the foregoing manner using the perfume oil concentrate for My Sin, and Arpege both by Lanvin, the pine or apple blossom scent of Magnus, Mabee and Reynard, Inc., and Toilet Water Concentrate Y of Lanvin-Charles of the Ritz, Inc., which is the perfume base for the perfume Yves St. Laurent.

Adding scents to papers became extremely successful in the ’70s and ’80s, finding success both with kids (who bought novelty stickers by the droves) and as a marketing tool (ever try a perfume in a magazine?).

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More controversial than they look. (via Amazon)

The concept, which has fallen out of patent ownership by now, had a bit of a resurgence a few of years ago, when the U.S. Postal Service added it to a popsicle-themed stamp series. But it’s worth reminding everyone that despite the fact that the scents are fun, we’re ultimately dealing with chemicals here, and that led the American Lung Association (a long-time USPS partner) to oppose the use of the stamps on the grounds that the fragrance could create problems for people with asthma.

So yes, even scented stickers have become problematic in the modern day.

“It’s kind of a crazy idea but a simple one. If you have a cellphone in your pocket and want to silence an incoming call, you don’t have to pull it out of your pocket. You could just drag your fingernail on your jeans.”

— Chris Harrison, a researcher at the Human-Computer Interaction Institute at Carnegie Mellon University, discussing the concept of “Scratch Input,” a form of interface that relies on the use of scratching as a form of interaction. Harrison, who spoke to Wired in 2009 about the idea, noted that one of the goals of the project was to help find more naturalistic approaches to human-computer interaction.

In many ways, scratching is the ultimate form of analog innovation. The ability to combine scratching with paper gave stickers and card stock superpowers that built billion-dollar industries.

Scratching tells us things about other people—and not just that they’re itchy, either. Various business texts about body language suggest that nose-scratching is a sign of dishonesty … or a cold.

And often, scratched surfaces create new shapes to play with—for example, the way that record scratches became a fundamental element of hip-hop music in the 1970s.

Scratching has been a fundamental part of human interaction, but it doesn’t seem like it stands a chance of making the leap into modern technology—in part because we don’t have the right interface for it. Glass is not particularly forgiving when it comes to scratches.

Back in 2019, a French researcher named Marc Teyssier came up with a new type of interface for communicating with our phones, which used realistic-looking skin, not unlike the kind that’s frequently very itchy. Speaking to The New Scientist, Teyssier noted that he wanted to be able to “pinch” his phone—not like a gesture at the top of the screen, but an actual pinch.

The response has been … well, you know. Let’s just say that Steve Jobs was probably right not to go with a lump-of-flesh iPhone prototype.

But the odd nature of that experiment is a great reminder … despite the fact that we have multitouch, we don’t have the full range of touch for our devices just yet. And we may not get it at all, because there are bigger fish to fry.

We’re only scratching the surface.


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Ernie Smith

Your time was just wasted by Ernie Smith

Ernie Smith is the editor of Tedium, and an active internet snarker. Between his many internet side projects, he finds time to hang out with his wife Cat, who's funnier than he is.

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