Mr. Holmes, now 24, was arrested in the mass shooting at an Aurora, Colo., movie theater early Friday that killed 12 people and injured 59.
He grew up in San Diego and later attended the University of California, Riverside, graduating with honors with a degree in neuroscience. Last year, he moved to Colorado and enrolled in the neuroscience program at the University of Colorado, Denver.
In the six-year-old video, he appears to be slightly nervous during his discussion of “temporal illusions” at a science camp at Miramar Community College in San Diego.
“Over the course of the summer, I’ve been working with a temporal illusion. It’s an illusion that allows you to change the past,” Mr. Holmes says in the video.
During the introduction to his presentation, he was described as having goals “to become a researcher and to make scientific discoveries.”
“In personal life,” the introduction continued, “he enjoys playing soccer and strategy games, and his dream is to own a Slurpee machine.”
Duration : 0:2:9
First 3 games, Highlight film. #74