Pigs can learn to manipulate joystick and react to video game screen, researchers say

Omelette, Hamlett, Ebony and Ivory, the pig subjects in a Purdue University study, were able to use a joystick to play a multilevel version of a game that loosely resembles Pong. 

Study shows pigs have more mental and behavioural flexibility than previously known

Omelette works the joystick for a video game as part of a study of porcine intelligence. (Penn State College of Agricultural Sciences)

Remember when Charlotte spelled out "Some Pig" with her spiderweb?

It was a testament to the gentle intelligence of a pigs (or one pig in particular, in the classic children's story Charlotte's Web).

Now, researchers in Indiana have proven that pigs can learn to play video games.

Omelette, Hamlett, Ebony and Ivory, the subjects in the Purdue University study, were able to use a joystick to play a multilevel version of a game that loosely resembles Pong. 

"One thing it clearly tells us is that pigs have a lot more mental flexibility and behavioral flexibility than we previously knew," Candace Croney, the study's lead author, told the Calgary Eyeopener. "They're frankly more cognitively sophisticated, and have the ability to learn things that we previously would not have understood."

Ebony the pig gets into the game. (Penn State College of Agricultural Sciences)

Croney, a professor of animal behaviour and a director at the Center for Animal Welfare Science, said the researchers used food rewards and words of encouragement to see how far the pigs could go.

"Well, you know, they're pigs and so they are food motivated," she said. "So we definitely used treats. One of the things that we did also use very effectively was just positive social interactions with them, petting, verbal reinforcement. All those seem to be really motivating to them, and frankly, sometimes even more motivating than food, particularly when things got frustrating for them."

The game itself is fairly simple. The pigs could operate a joystick to hit targets that would appear as lines around the four borders of the screen.

"All they have to do to hit that target is move a cursor that's located in the centre of the screen to one of those four blue borders or sides, and they've hit a target," Croney said. "If they do that multiple times in a row and complete the task, the computer makes the task a little bit harder. So randomly one of those sites or targets will disappear. And if they then move the cursor into that particular side that's missing, it's an error."

Omelette the pig. (Penn State College of Agricultural Sciences)

Crawley said the pigs showed an ability to react to what was happening on the screen.

"It really was, frankly, an attempt to use this established technology to really evaluate the pigs' ability to learn this very simple task, which reflects a certain level of conceptual ability and cognitive sophistication," Croney said. 

The pigs could operate the joystick by pushing it with their snouts, or using their mouths.

For Croney, the results were eye opening.

"It changed the way I look at pigs," she said. "It changed the way I think about everything we do, where we use pigs for our benefit, maybe without quite as much thought as to how it impacts them or what their interests are."

The task was designed to compare pigs with other species taking the same test, Croney said, so non-human primates, such as monkeys and chimpanzees. 

"And while our pigs are nowhere near as competent as monkeys and chimpanzees, what's really is cool is, they could do the task to any degree and conceptually grasp any concept of what they were manipulating, which is the joystick having its effect on the computer by way of the cursor," she said. "And that they were actually controlling that movement is the thing that I find really remarkable."

Hamlet the pig uses his mouth to skillfully manoeuvre the controls. (Penn State College of Agricultural Sciences)

Croney said even though the pigs couldn't master the game as well as primates, the results suggest that we may have been underestimating pigs' intelligence.

"The fact they can do it at all suggests that there may be other things that they know, they understand, they learn that they can do, that really should raise questions for us about what else they might be capable of, that we just haven't found good ways to ask them about," she said. 

Listen to the full interview here:

With files from the Calgary Eyeopener.


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