Self-determination theory: A quarter century of human motivation research

In the 1970s and 1980s, Richard Ryan, PhD, and Edward Deci, PhD, then both at the University of Rochester, began fleshing out a humanist theory of motivation that differed from the behaviorist theories that dominated at the time. “Up to that point, everything revolved around the role of reinforcement. We said, ‘Let’s start with human nature and people’s inherent propensities to learn and to be curious,’” said Ryan, now a professor at the Institute for Positive Psychology and Education at Australian Catholic University. “It was a kind of Copernican turn in the field of motivation.”

Over the next few years, he and Deci took what they called a “brick by brick” approach to fleshing out their theory: methodically testing elements of SDT across multiple contexts, refining the theory, and adding and testing new sub-theories as they went. Though they took a measured approach, it resulted in a steady stream of evidence for SDT. By the time their American Psychologist paper was published, research on SDT science “had hit a critical mass,” Ryan said. The influential paper reviewed the empirical support for the theory and summed up the framework in a tidy package that psychological scientists could run with—and run they did.

A quarter century later, SDT is established as an evidence-based framework for understanding human motivation, personality development, and wellness. It has generated thousands of publications, spawned the nonprofit Center for Self- Determination Theory and a triannual SDT conference, and resulted in practical applications to increase positive outcomes in education, parenting, organizations and workplaces, health and medicine, and beyond.

Ryan, R. M., & Deci, E. L. (2000). Self-determination theory and the facilitation of intrinsic motivation, social development, and well-being. American Psychologist, 55(1), 68–78

SDT describes factors that help or hinder human motivation, including both internal motivation and external influences. At the core of Ryan and Deci’s theory was the concept that self-directed motivation and personal growth rely on three psychological needs: autonomy, competence, and relatedness.

When those needs are met, the research showed, people tend to be more self- motivated, feel more satisfied, and experience greater well-being. By contrast, when people are motivated to act because of external pressures—or internal pressure to live up to external expectations—they have more trouble staying engaged and feel less fulfilled.

As Ryan, Deci, and a host of other scientists have built on those findings, SDT has evolved into a metatheory, encompassing six smaller sub-theories, that provides a global framework for understanding human motivation and development across cultures.

In the classroom, autonomy might look like giving students more choices in what they study or how they demonstrate mastery of a topic. Some may choose to take an exam, for instance, while others may opt to give an oral presentation. Meanwhile, incorporating well-designed group work or peer feedback could help learners tap into the need for relatedness.

In 2011, Levesque-Bristol launched a pilot of her IMPACT (Instruction Matters: Purdue Academic Course Transformation)opens in new window program to improve student-centered learning by supporting all three psychological needs identified by SDT. Since then, more than 580 courses at Purdue have been redesigned through the program. Students in IMPACT courses report high levels of self-determined motivation and low levels of non-self- determined motivation, and more than 8 in 10 perceive the course to be student centered. What’s more, in courses with high numbers of failing grades, Levesque-Bristol and her colleagues saw significant decreases in failure rates, sometimes by as much as 20%.

IMPACT has since been adapted by about 20 other universities in the United States. More broadly, principles of SDT have been incorporated into education and teacher training curricula in many locales, including countries as varied as Singapore and Belgium, Ryan said. Yet despite the success of efforts like IMPACT, SDT hasn’t been embraced in U.S. education as widely as proponents would like. “There is still a lot of room to apply these principles,” Levesque-Bristol said. And, in spite of the demonstrated benefits of such student-centered learning, the idea sometimes butts up against traditional ideas of competition and control over the classroom—especially in university settings where there’s often a lot of pressure on both students and professors to excel.

“Students often come into [higher education] excited to learn, but it doesn’t take long for them to start feeling the weight of the pressure. That’s not self-determined,” she added. “We want to create environments where you feel like you can grow and create and develop passion and creativity.”

The classic SDT framework describes motivation as a continuum from internal factors to external influences. But Legault recognized that there’s more to the story than whether motivation is internal, external, or somewhere in between. “It’s also about the content of that motivation,” she said. For instance, someone might be motivated to become less racially biased in the service of personal growth. For others, the same goal might be driven by concern for the welfare of others. Though the emphasis is different, both drives are self-determined. Legault is exploring how self-determined motivation differs from person to person and from situation to situation—and how tapping into those differences could inspire people to act in more prosocial ways.

In a study under review for publicationopens in new window, she compared two antiracist messages influenced by SDT—one self-focused and the other focused on empathy for others—with an externally driven message that encouraged antiracism as a way to conform with social norms. Of the three approaches, the SDT message built on interpersonal empathy was most likely to increase awareness of bias, egalitarianism, antiracism, and allophilia (positive feelings for members of a different group). The findings suggest that not all types of internal motivation are created equally.

Beyond reducing prejudice, Legault’s work includes applying SDT to craft more nuanced motivational messages in areas such as encouraging body positivityopens in new window and embracing pro-environmental behaviorsopens in new window like the adoption of solar panels (Body Imageopens in new window, Vol. 41, 2022; in R. M. Ryan [Ed.], The Oxford Handbook of Self-Determination Theoryopens in new window, Oxford University Press, 2023). “Public service messages usually have a noble goal, but most messages tell you what to think or feel or do,” she said. “By understanding why different types of self-directed motivation are meaningful, we can better inform messaging and intervention efforts.”

Deci and Ryan’s landmark 2000 paper was published in a special issue of the journal devoted to positive psychology (American Psychologist, Special Issue: Positive Psychologyopens in new window, Vol. 55, No. 1, 2000). At the time, “positive psychology” was a freshly coined term and a hot trend among many psychological scientists. As positive psychology has evolved, SDT has taken on a movement all its own—and has extended beyond the realm of positivity, Ryan said. “SDT is concerned with human potential and how it can be actualized, but it's also about understanding [factors that] degrade, undermine, and harm people’s motivation and their wellness,” he added.

He and Deci sensed early on that they’d tapped into something important with their theory. Yet they took time to make their case. “Our rule all along has been to build this theory slowly and not make mistakes,” Ryan said. As with any field, researchers still debate some of the details and continue to test and hone the theory and its component parts. Yet the body of evidence supporting SDT is hard to deny. In a recent meta-review that examined 60 meta-analyses of SDTopens in new window, Ryan and colleagues showed strong support for the validity of the framework, and for its relevance and utility to domains including organizational psychology, health care, parenting, and education (Psychological Bulletinopens in new window, Vol. 148, Nos. 11–12, 2022). It has even spilled into technology design, where the framework helps developers design apps and video games that are more likely to satisfy a user’s psychological needs than leave them frustrated.

What began as a line of inquiry between two friends at the University of Rochester has grown into a scientific community that includes thousands of active researchers around the world. “The theory is owned by everybody, and there are a lot of young researchers with a lot of energy and creative ideas,” Ryan said. “Our goal is to support them in engaging this framework to both do good research and to change the world in a better way.”