What makes self-directed learning effective?

"In recent years, educators have come to focus more and more on the importance of lab-based experimentation, hands-on participation, student-led inquiry, and the use of "manipulables" in the classroom. The underlying rationale seems to be that students are better able to learn when they can control the flow of their experience, or when their learning is "self-directed"....

While the benefits of self-directed learning are widely acknowledged, the reasons why a sense of control leads to better acquisition of material are poorly understood.... In an article published in Perspectives on Psychological Science, a journal of the Association for Psychological Science, researchers Todd Gureckis and Douglas Markant of New York University address this gap in understanding by examining the issue of self-directed learning from a cognitive and a computational perspective."