Washington ? For the first time, researchers have demonstrated the ill effects of mindless reading, a phenomenon in which people take in sentence after sentence without really paying attention.

Mindless reading occurs when the reader goes over same paragraph three times. Or when the reader gets to the end of a page and realizes what it says is a blur.

It is the literary equivalent of driving for miles without remembering how you got there, an event so common many people don’t even notice it.

In a new study of university students, researchers from the University of Pittsburgh in the United States and the University of British Columbia in Canada established a way to study mindless reading in a lab.

Their findings showed that daydreaming has its costs.

The readers who zoned out most tended to do the worst on tests of reading comprehension – a significant, if not surprising, result.

The study also suggested that zoning out caused the poor test results, as opposed to other possible factors, such as the complexity of the text or the task.

The researchers hope their work inspires additional research into why zoning out happens and what can be done to stop it.

For now, they want the problem to be taken seriously.

“When you talk about this work at conferences, it does lend itself to a lot of jokes,” acknowledges University of Pittsburgh professor Erik Reichle, co-leader of the study.

“It’s so ubiquitous. Everybody does it,” he said. “I think that’s one of the main reasons it’s been overlooked. And there’s been a view that it is tough to study experimentally. Hopefully, now, there will be more interest in the topic.”

The federal government is showing some.

Reichle and fellow psychology professor Jonathan Schooler did the study on a $691,000 grant from the Institute of Education Sciences, an arm of the U.S. Education Department. It is among 178 federally backed projects aimed at giving schools scientific bases for sound policies.

Over three experiments, students used computers to read the first five chapters of Leo Tolstoy’s “War and Peace.” (Reichle wanted boring reading – better for zoning out.)

Reichle said the dry text itself did not skew the results toward mindless wandering; the students were on alert, unlike the typical reader.

Participants were told to monitor and report instances of zoning out as they read text on a computer. Half got computer reminders, too: “Were you zoning out?”

Despite all that, many still reported zoning out at a regular pace.

“That’s the amazing thing,” Reichle said. “It shows how often this can happen even under conditions that are designed to keep it from happening.”

The students said as their eyes scanned the words, their minds often were elsewhere.

They were hungry, or thirsty, or tired. They were thinking about plans, worries or memories. Some drifted into fantasies. Others stuck with the book, but their minds wandered into tangents about the plot.

Karen Wixson, a nationally recognized reading expert and professor of education at the University of Michigan, cautioned not to read too much into this.

“This is a long ways away from having implications for reading instruction,” Wixson said. “It could, eventually, down the line. But to draw inferences about this as a contributing factor toward reading comprehension would be a huge, huge leap.”

By the way, last sentence here. If you missed anything, there’s no shame in rereading.