RODENT -SELFIES- ROARS* : MASTER PRECIS

' Glued To Their Gadget ' : Our rodent selfies, ourselves. Rats with a very humanlike traits.

When Augustin Lignier, a professional photographer in Paris, was in graduate school, he began to ponder the point of picture-taking in the modern world :

Why did so many of us feel compelled to photograph our lives and share those images online?

It was not a novel question, but it led Mr. Lignier to a surprising place : Before long, he found himself building what was, in essence, a photo booth for rats.

He took inspiration from B.F. Skinner, the behaviorist who devised a test chamber to study learning in rats. The Skinner Box, as it became known, dispersed food pellets when rats pushed a designed lever.

It became one of the best-known experimental paradigms in psychology. Scientists found that reward-seeking rats became lever-pressing pros, pushing the bar down over and over again in exchange for food, drugs or even a gentle electric zap directly to the pleasure center of the brain.

Mr. Lignier built his own version of a Skinner box and released two rats inside. When the rats pressed the button inside the box, they got a small dose of sugar and the camera snapped a photo.

The resulting images were immediately displayed on a screen, where the rats could see them. [ '' But honestly, I don't think they understood it,'' Mr. Lignier said.]

The rodents quickly became enthusiastic button pushers.

But after this training phase, he made the rewards more unpredictable. Although the rats were still photographed every time they hit the button, the sugar, by design, came only occasionally.

Such intermittent rewards can be powerful, scientists have found, in keeping animals glued to their experimental slot machines. And indeed the rats persisted. Sometimes they ignored the sugar and just kept pressing the button.

Mr. Lignier noted a parallel. '' Digital and social media companies use the same concept to keep the attention of the viewer as long as possible,'' he said.

[ Emily Anthes ]