Holmes graduated from University of California, Riverside, in the spring of 2010 with a bachelor of science degree in neuroscience, said university spokesman Sean Nealon. No other details were immediately available about his life on campus, Nealon said.
In 2011, Holmes enrolled in the Ph.D. neuroscience program at the University of Colorado-Denver but was in the process of withdrawing, said spokeswoman Jacque Montgomery. University officials earlier said he was a student at the university's medical school.
Associated Press writers Eileen Sullivan in Washington, Amy Taxin in Orange County, Calif., and Dan Elliott and Colleen Slevin in Denver contributed to this report.