A native of Shanghai, Liu’s early interest in science stemmed from his collecting centipedes, beetles, and locusts as a child. He earned an undergraduate degree in biology at Fudan University in Shanghai and completed his doctoral research, focused on fruit fly memory, with Ron Davis at the Baylor College of Medicine in Houston, Texas.
As a postdoctoral fellow in the laboratory of Susumu Tonegawa at MIT, Liu and graduate student Steve Ramirez used optogenetic techniques to identify the neurons involved in encoding fear memories in mice. In a follow-up study, Liu and Ramirez used their understanding of fear memory formation to create a false fear memory of a harmless location. The work generated great scientific and public interest. The team’s two TED talks on this work have generated nearly 1 million views online. Liu and Ramirez were awarded the 2014 Smithsonian American Ingenuity Award and were runners-up for Science’s Breakthrough of the Year in 2014. Later research replaced negative memories with positive ones.
“For me, what made [Liu and Ramirez] successful was their fearlessness,” Sheena Josselyn of the Hospital for Sick Children in Toronto told Smithsonian last year. “They applied the best sort of mind power.”
“We hope that our work can lay the foundations for potential future treatments for memory-related disease,” such as Alzheimer’s disease and PTSD, Liu told Smithsonian.
Liu officially started at Northwestern this month. “Xu was much more than an accomplished and gifted scientist. His colleagues have noted his generosity, his mentorship of students, his genuine friendliness, and his sense of humor,” a release from Northwestern’s neurobiology department noted. “This is truly a great loss for . . . the larger neuroscience community at Northwestern and worldwide.”