Research Has Probably Been Overstating How Smart Dogs Are

And other science headlines you don't want to miss.
Dog holding stick

The Grossest Thing You’ll Touch At The Airport

Whenever I travel, I worry about getting sick from being on airplanes, surrounded by rogue sneezes and coughs. In a study from March, data scientists calculated the potential risk of catching something from your planemates, and found that if you sit directly in front or back of a sick person you have an 80 percent chance of getting infected—even on the other side of the aisle.

But for whatever reason, I didn’t worry too much about the airport itself—until now. A new study in BMC Infectious Diseases looked for respiratory viruses on 90 surfaces at Helsinki Airport, which 18.9 million passengers passed through in 2017. They collected surface and air samples weekly, three different times, at peak flu season.


They found at least one respiratory virus in ten percent of their samples, so nine out of 90. This included: “A plastic toy dog in the children’s playground (2/3 swabs, 67 percent); hand-carried luggage trays at the security check area (4/8, 50 percent); the buttons of the payment terminal at the pharmacy (1/2, 50 percent); the handrails of stairs (1/7, 14 percent); and the passenger side desk and divider glass at a passport control point (1/3, 33 percent),” the paper said.

Out of all the surfaces they tested, the plastic security trays showed the most potential risk for infection, and “and handling these is almost inevitable for all embarking passengers,” the paper said.

In a surprising (to me) turn of events, they did not detect any respiratory viruses on the toilets—not on the upper surface of the toilet bowl lid, the button for flushing, or the lock at the door inside the toilet. They also did not detect any respiratory viruses on the armrest of a chair in the waiting area, the handrails of an escalator, the buttons of an elevator, the trolley handles for luggage, or the touch screen of the check-in machine—which means I’ve been applying hand sanitizer at all the wrong times.

Still, for us germaphobes, remember they only sampled three times. Who is touching what in an airport, and with what virus, surely varies widely. But their findings probably mean you should try not to bury your face in your hands in frustration while your bag is getting searched— at least, not before washing your hands.


Your Dog Isn’t That Special

When Stephen E. G. Lea, an emeritus professor of psychology at the University of Exeter, was editor of the research journal Animal Cognition he received many papers on the cognition of animals. But he began to notice that one animal seemed to be winning the intellectual arms race, at least based on the claims the papers were making: Dogs.

“I noticed that many of the claims that were being made for dog intelligence could equally, and in some cases better be made for the intelligence of some of these other animals,” Lea tells me. “So I wanted to review as much as I could of this literature to see how it stacked up.”

In a new paper in Learning and Behavior, Lea and collaborators reviewed evidence from more than 300 papers and found several cases of "over interpretation" in favor of dogs' abilities. The analysis compared the findings of dog’s cognitive ability, to other animals that are biologically similar to dogs, like hyenas, bears, seals, sea lions; animals that socially hunt like dogs do, including chimpanzees and dolphins; or animals that were similarly anthrogenic, aka have a domestic relationship to humans.

Many studies found that dogs were the winners in areas of sensory cognition, physical cognition, spatial cognition, social cognition and self-awareness. But Lea and his collaborators found that for each of these “wins,” they could find examples where the species they were compared to did at least as well as dogs do in those tasks.


"During our work it seemed to us that many studies in dog cognition research set out to 'prove' how clever dogs are," Lea said in a press release.

Previously, psychologists weren’t that interested in doggy smarts, Lea tells me. But there has been a lot of progress in understanding dog intelligence, especially in the past three decades. “In our excitement at new discoveries, my co-author, Britta Osthaus, and I felt that we—the scientific community as a whole, that is—had sometimes lost sight of basic disciplines in interpreting animal behavior,” he says.

For one, we shouldn’t justify a simple, sometimes instinctual or mechanistic behavior with an elaborate cognitive explanation. Some experiments he saw described behavior as empathetic or insightful, but those behaviors could also be explained by basic conditioning, like training and association. “You need to ask yourself every time, ‘Could I train a slug to do this?’” Lea says.

He doesn’t think that researchers consciously do this, but that scientists who work with animals, and especially dogs, tend to like and respect them—which is a good thing. (We don’t want animal haters researching animals.) But this quality might make it easier to imbue their canine subjects with qualities that just aren’t there.

And who cares if scientists think your dog is a genius? For one, the belief that dogs are exceptionally smart might lead to an over-concentration of research on dog intelligence. One of the main reasons we study animal intelligence is to compare cognition levels between many species, to understand why evolution has led to advanced intelligence in just a few of them.


“If we want to understand where intelligence comes from, evolutionarily speaking, we need to look at lots of different kinds of animals, not just a handful,” Lea says.

The other issue is that believing dogs are more special than other animals could lead us to think less of other animals, and treat them worse accordingly. Animals like pigs and goats—which have been found to rival dogs on some cognitive tasks—don’t get the same royal treatment as dogs do. “Our estimation of their level of intelligence tends to influence how seriously we take their welfare—and it probably should, though there is an argument to be had about that,” Lea says.

This Is Why Your Vision Doesn’t Go Dark Each Time You Blink

We blink every five seconds, and when we do, our eyelids close—interrupting the information we get through our eyes about the outside world. But we generally don’t experience these interruptions. We see our surroundings as a stable image, rather than one that’s constantly going dark.

How is this possible? The brain must use memory to fill in that gap, says Caspar Schwiedrzik, the head of the neural circuits and cognition lab at the European Neuroscience Institute in Germany, and a co-author of a new paper on this phenomenon. “Such a memory can in principle help us in perceiving whenever the visual input is interrupted, noisy, or ambiguous,” he tells me. The study, published in Current Biology, found out where this perceptual memory is located in the brain, and how it works.


Schwiedrzik and his collaborators were able to record directly from the brains of people who have epilepsy, using pre-existing electrodes implanted in their brains. “It's an incredible opportunity to directly observe brain activity in humans,” he says. “This is usually only possible in animal models, and the methods usually available in humans (like magnetic resonance imaging) are all indirect. “

Rather than waiting for people to blink, the participants were shown images intermittently, sometime slightly different from one another, with a brief gap between each one. The researchers asked the participants to describe what they saw, to see if the first image a subject saw affected their perception of the image after that gap. “This is what we found, and that is an effect of perceptual memory,” Schwiedrzik says.

In the past, it was thought that perceptual memory took place in parts of the brain that are dedicated to visual perception, which are located in the back of the brain. But Schwiedrzik saw brain activity at the other end of the brain, in the frontal cortex—areas which are usually associated with working memory, decision making, and aspects of social cognition.

“An interesting commonality between many of the known functions of the medial frontal cortex is that they require the integration of past and current information, similar to what one would need for perceptual memory to take effect,” Schwiedrzik says.


Intriguingly, Schwiedrzik was also able to study a patient who had had part of their medial frontal cortex removed from a previous illness. In that person, he didn’t observe the same effect as the other subjects; prior images didn’t have an effect on their perception of subsequent ones. "We were able to show that the prefrontal cortex plays an important role in perception and in context-dependent behavior," he said in a release.

The next thing he’d like to study: the role that confidence plays into this perceptual memory.

Health reads you don’t want to miss:

How I discovered my depression—and began to confront it. By David M. Perry in Pacific Standard.
A vulnerable account of one man accepting his mental health condition, and finally seeking help at 46.

Nobody Was Going To Solve These Cold Cases. Then Came The DNA Crime Solvers. By Jessica Testa in BuzzFeed.
DNA testing could help find criminals from long-ago cold cases, but that’s not what the DNA Doe Project does. “Its volunteers are devoted to the dead, rather than the living. They don’t hunt elusive suspects; they put names to unidentified bodies.”

He got schizophrenia. He got cancer. And then he got cured. By Moises Velasquez-Manoff in the New York Times. How did a bone-marrow transplant, for a patient’s leukemia, also help treat his delusions?

Paper Trails: Living and Dying With Fragmented Medical Records. By Ilana Yurkiewicz in Undark.
“Every year, an untold number of patients undergo duplicate procedures — or fail to get them in the first place — because key pieces of their medical history go missing.”

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