Reflecting on five decades of groundbreaking sleep research

Dr. Krueger in the audience, laughing during one of the presentations.

Dr. James Krueger is recognized as a leading sleep expert and his contributions to the understanding of sleep have earned him international recognition and had a profound impact on his field of study.

His career of discovery and innovation in sleep science has spanned more than five decades, including the past 27 years at Washington State University, where he leads groundbreaking research in the Department of Integrative Physiology and Neuroscience.

During his career, Krueger published more than 400 manuscripts and 390 abstracts and presented at more than 330 symposiums and seminars. He holds seven patents and is the recipient of dozens of prestigious honors and awards, including the Sleep Research Society’s Distinguished Scientist Award, the society’s highest award that recognizes significant, original, and sustained scientific contributions to the sleep and circadian research field.

Krueger’s research focused on the biochemical regulation of sleep, how microbes affect sleep, the function of sleep, and the brain organization of sleep. Some of his notable accomplishments include identifying an endogenous sleep-promoting Factor S as a muramyl peptide, discovering the physiological roles of cytokines in sleep regulation and multiple other sleep regulatory substances, detailing the dramatic changes in sleep over the course of infectious diseases (Hippocrates suggested this happened, but 2,400 years passed before Krueger showed how infections altered sleep), and documenting sleep initiation within small neuronal/glial networks. He is also at the forefront of the debate concerning the function of sleep. His favorite theories posit sleep serves an immune function and that sleep first evolved to maintain brain plasticity. In addition, in collaboration with WSU mathematicians, he developed a pair of mathematical models of sleep regulation. Collectively his research led to the idea that sleep is an emergent manifestation of the human holobiont condition. (A holobiont is a collection of different species that live closely together forming a unit thus forming a distinct ecosystem through their symbiotic relationships, e.g., humans and their microbiomes.)

“If my science is remembered 100 years from now, it’ll be for two things,” Krueger says. “One, that bacteria are playing a normal part of the physiologic regulation of sleep, and two, the idea that any collection of viable neurons and glia, whether in an animal or not, will oscillate between sleep-like and wake-like states.”

Group of speakers gathered around Dr. Krueger.

In addition to his research contributions, Krueger is known for his dedication to education and mentorship. He trained countless students and researchers who have gone on to make their marks in science and medicine.

Krueger joined WSU in July 1997 as the IPN chair and professor and in 2006 was promoted to Regents Professor.

Upon arrival at WSU as chair, he was tasked with implementing a new neuroscience program without any new financial or personnel resources. The IPN faculty and staff already had full-time jobs, but through their brilliance, extraordinary effort, curiosity, and dedication the program thrived. 

Dr. Krueger at the podium during his closing presentation at the symposium.

“We were one of the first, if not the first, in the country to have an undergraduate neuroscience program,” Krueger said. “Working with the students was a joy. It was easy to mentor them because they were very bright and hard-working.”

By 2003, Dr. Krueger had organized an informal sleep research group at WSU-Pullman, and by 2004 his efforts led to a congressional earmark of $4.5 million to create the WSU-Spokane Sleep and Performance Research Center.  Dr. Greg Belenky was then recruited to WSU-Spokane as its director.  Dr. Hans Van Dongen is currently the SPRC director. 

Within its first five years, SPRC faculty generated more than $32 million in research grants, published 322 scientific papers, trained 155 WSU undergraduate students and 44 graduate students, and gave 330 seminars/symposium talks worldwide. 

“It was an administrative accomplishment and, more importantly, intellectually rewarding being part of that effort with so many outstanding WSU faculty, students, and staff. Seeing it flourish, like it has, is incredibly satisfying,” Krueger said.

His many responsibilities after joining WSU often competed with one of his deepest passions, teaching students.  

“If I had any regrets about my days in Pullman, it is I didn’t teach as much as I wanted to. I was so busy with chairing, and by the time I got done with chairing, I had four NIH RO1 grants simultaneously, which I kept for the next 20 years. Even after I moved to Spokane, I worked with many students in the lab, but I couldn’t spend a lot of time teaching in the classroom, as I would have lost the grants. There just wasn’t enough time.”

Before coming to WSU, Krueger received a bachelor’s degree from the University of Wisconsin, a doctorate in physiology from the University of Pennsylvania, and a Doctorem Medicinae Honoris Causa from the University of Szeged. He did postdoctoral work at Harvard Medical School and held faculty positions at Rosalind Franklin University and the University of Tennessee Medical School.

Krueger is the recipient of numerous prominent awards including a Javits Award from the National Institutes of Health/National Institute of Neurological Disorders and Stroke, a Taniguchi Fellow, Kyoto, Japan, recipient of two W. M. Keck Foundation research awards, and the Eminent Faculty Award at WSU. He was elected to the Washington State Academy of Sciences in 2012. Krueger’s scholarly publications have been cited over 27,000 times.