The world’s most popular online course is a general introduction to the art of learning, taught jointly by an educator and a neuroscientist.

“Learning How To Learn,” which was created by Barbara Oakley, an electrical engineer, and Terry Sejnowski, a neuroscientist, has been ranked as the leading class by enrollment in a survey of the 50 largest online courses released earlier this month by the Online Course Report website.

The course is “aimed at a broad audience of learners who wanted to improve their learning performance based on what we know about how brains learn,” said Dr. Sejnowski, the director of the Computational Neurobiology Laboratory at the Salk Institute for Biological Studies in La Jolla, Calif.

With 1,192,697 students enrolled since the course was created last year, “Learning How to Learn,” which is offered by the University of California through Coursera, an online learning company which has partnered with a number of universities, has narrowly edged out the more tightly focused course, “Machine Learning,” taught by Stanford University professor Andrew Ng, which currently has 1,122,031 students enrolled.

The similar enrollment figures are striking in part because the field of machine learning has become one of the hottest university areas of study in recent years. High technology companies are competing intensely in Silicon Valley and elsewhere for newly minted data scientists.

The enrollment figures indicate that massively open online courses, or MOOCs, which in 2012 emerged as a potentially disruptive force that some believed might threaten the modern educational system, are continuing to evolve and gaining broad acceptance as part of an increasingly diverse marketplace for online education.

The Achilles heel of the MOOC phenomena has been that while enrollments have been huge, the number of students who actually complete courses for credit has remained low. That has led traditional educators to argue that the new technology would fail because students are generally less motivated to complete coursework online.

The completion rate — or “stickiness” — of the “Learning How to Learn” course has been above 20 percent, said Dr. Sejnowski, roughly twice the average for most MOOCs. He said the course is now attracting about 2,000 new students a day from 200 countries. The course was created after the two researchers met at the National Science Foundation-financed Science of Learning Center at the University of California at San Diego, which Dr. Sejnowski directs.

Dr. Oakley, a professor of engineering at Oakland University in Michigan, acknowledged that although only roughly 50,000 of the more than one million enrollees in her course had actually received a certificate for the course, certification was the wrong metric to understand the impact of the new form of online education.

“People frame it incorrectly,” she said. “Students are clearly hungry to learn, and they’re particularly hungry for practically useful, scientifically based information told in a way that they can really get it.”

She is a passionate advocate of the MOOC concept against a range of academic critics. She recently wrote an essay defending online education technologies. Dr. Oakley claims there is evidence that the course has touched a nerve more broadly from a diverse audience that is eager to acquire to improve their learning skills.

She cited a range of groups who are promoting the course from the California State Prison System, federal K-12 teacher certificate programs, as well as refugee camps in Somalia and Sudan, where she asserted that students threatened to overwhelm the meager Internet bandwidth available in those countries.

There is evidence that MOOCs are being fed by a broad base of “life-long learning” interest said Merrill Cook, editor of the Online Course Report.

“Your average person taking a MOOC has a bachelors degree and is in their 30s,” he said.

He noted that there is now an increasing proliferation of a range of different online learning offerings beyond MOOCs. That can be seen in the shift in strategy in one of the earliest commercial efforts in the new approach to teaching.

Take Udacity, which was founded by Sebastian Thrun, an artificial intelligence researcher who taught at Stanford and then founded Google’s X Lab research effort. After first offering MOOCs, the Mountain View, Calif.-based firm shifted its strategy and now offers “Nanodegrees” to train online customers in very specific skills.

“If I look back at the MOOC hype, what actually happened was that people equated a cheaper delivery method with the replacement of the entire educational system,” Dr. Thrun said. “A cheaper technology is not the same as a business revolution.”