When University of Washington psychology professor Kristina Olson got the call telling her she’d be receiving one of the MacArthur Foundation’s “genius grants,” she had to ask if they had the right number.

“For a few days after, I continued to think it was an elaborate prank,” Olson said in a news release.

But there’s no denying it now: On Thursday, Olson was listed among this year’s MacArthur Fellows, which earns her a no-strings-attached $625,000 stipend that’s spread out over five years. Other fellows include writers, artists, musicians, activists, scholars and even an investigative journalist (Ken Ward Jr. of the Charleston Gazette-Mail in West Virginia).

Olson is known for her work at the UW’s Social Cognitive Development Lab and her leadership of the TransYouth Project, the nation’s largest longitudinal study of transgender children. She’s considered one of the country’s foremost researchers into child gender identity.

Early results from the project suggest that children who have socially transitioned to the gender they identify with embrace that gender as firmly as children who identify as the gender they were born with. Such children had rates of depression and anxiety no higher than two control groups — their own siblings and a group of unrelated children matched to age and gender.

Olson and her colleagues are now recruiting children who don’t conform to their birth gender, and have not made a social transition. Previous studies have shown that such gender-nonconforming children do face higher rates of anxiety and a higher risk of mental health problems. Eventually, the project will include teenagers who are in the process of transitioning as well as intersex children.

In announcing the award, the MacArthur Foundation cited Olson’s work “advancing the scientific understanding of gender and shedding light on the social and cognitive development of transgender and gender-nonconforming youth.”

“I’m incredibly honored to have the work of my team celebrated by the MacArthur Foundation,” Olson said.

Olson, 37, hasn’t yet decided how she’ll use the grant. One priority is to support others in their research and training, such as through a mentorship program for underrepresented undergraduate students interested in gender research at UW. Such a program is likely to focus on LGBTQ students, students of color, first-generation college students, and those from small colleges with fewer resources for research.

The other priority, she said, is “to take on riskier, challenging new projects that wouldn’t be supported by traditional grants.”

As large as it is, the MacArthur grant isn’t the biggest award Olson has received this year. In April, she won the National Science Foundation’s Alan T. Waterman Award for early-career researchers, which brought her a $1 million, five-year research grant.

Olson is the first UW faculty member to receive the Waterman Award, and the 12th person to win a MacArthur grant while serving on the UW faculty. The most recent previous winner was computer scientist Shwetak Patel, who won his “genius award” in 2011.