Larry J. Young (1967–2024)

Larry Young, the self-described "guy who spends his days thinking about love and bonding in terms of biochemical reactions in localized circuits of the brain" (The Chemistry Between Us1Young L. Alexander B. The chemistry between us: Love, sex, and the science of attraction. Current, 2012Google Scholar), passed away, too early, in March 2024. He was a brilliant scientist who used prairie voles (Microtus ochrogaster) and other rodents to pioneer a deeper understanding of the mechanisms by which the neuropeptides oxytocin and vasopressin act in the mammalian brain to mediate affiliative behaviors. He was also so much more—to his family, his field, his trainees and colleagues, and the larger world with whom he so skillfully communicated his complex studies that have illuminated how the social brain works. Larry grew up in the small town of Sylvester, Georgia, where his parents were successful peanut farmers. As a boy, he spent his days fishing, hunting, and checking his traps, his pet possum draped around his shoulders. His mother often lamented over the numerous pairs of shoes he wore out each year. Larry's second love was his chemistry set, and when it was too dark to hunt and fish, he would dream up various experiments. His family always knew he was destined for greatness, but never imagined he would become a world-famous neuroscientist and a leader in the field of social behavior. Larry was fascinated by the intricacies of living things and entered the University of Georgia on a Pell Grant to pursue a career as a veterinarian. His plans changed after volunteering in the endocrinology lab of Dr. Mark Brown and Dr. Arden Lea dissecting mosquito brains. Intrigued by the genetic basis of behavior, he changed his major to biochemistry and hoped to uncover life's molecular mechanisms. Larry applied to just one graduate program to work with David Crews at the University of Texas at Austin. There he discovered the power of hormones while researching unisexual whiptail lizards. In 1994, he moved to Emory University to work with Tom Insel on an emerging rodent model for studying the neurobiology of monogamy. Thus began a rich scientific career championing the prairie vole as a window into the neurochemistry behind complex social behaviors relevant to the human condition. When Larry started at Emory, it was becoming apparent that the reproductive strategies of vole species, whether polygamous or monogamous, varied dramatically based on the distribution of oxytocin and vasopressin receptors in the brain, unlike other neuroactive peptides or reproductive hormones. Larry's efforts focused on the how questions stemming from these observations in ways that have hinted at answers to the evolutionary why questions everyone loves asking. Early on, he showed that the phylogenetic plasticity of the oxytocin and vasopressin systems across species mirrors individual differences within a species and correlates with behavioral differences in their social interactions—including the likelihood of forming monogamous pair bonds. Importantly, Larry was not just satisfied with correlation but strove for causation. He was a pioneer in a growing research strategy to manipulate genes, brain areas, and circuits to effect social behavior. Larry's lab grew as he transitioned from postdoc to tenure-track faculty and was promoted to William P. Timmie Professor and Division Chief of Behavioral Neuroscience and Psychiatric Disorders in the Emory National Primate Research Center. He went on to publish a slew of now classic papers that have elucidated the roles of oxytocin and vasopressin in specific regions of the central nervous system in mediating social behaviors. His 2001 study,2Young L.J. Lim M.M. Gingrich B. Insel T.R. Cellular mechanisms of social attachment. Horm.Behav. 2001; 40: 133-138Google Scholar in which he pharmacologically blocked oxytocin receptors in the prairie vole's nucleus accumbens and prelimbic cortex during "cohabitation," identified those regions as necessary sites for the neuropeptide's action in pair bond formation. In 2004,3Lim M.M. Wang Z. Olazabal D.E. Ren X. Terwilliger E.F. Young L.J. Enhanced partner preference in a promiscuous species by manipulating the expression of a single gene.Nature. 2004; 429: 754-757Crossref PubMed Scopus (512) Google Scholar with graduate student Miranda Lim, he employed a viral gene transfer strategy to over-express the vasopressin 1a receptor in the ventral pallidum of polygamous meadow voles (M. pennsylvanicus), resulting in a behavioral phenotype that more closely resembled the monogamous prairie vole. These studies were the first to show that modifying the expression of a single gene could dramatically alter the selective affiliative preferences toward a partner—leading hundreds of spouses to write to Larry wanting to know how they could change their polygamous partner into a more monogamous one. Voles are obviously not humans, and Larry the "Love Doctor" was careful to make the distinction whenever he talked about his research. Nevertheless, his research pushed the envelope using prairie voles to model various natural behaviors that the public often assumes have only evolved in primates. With graduate student James Burkett,4Burkett J.P. Andari E. Johnson Z.V. Curry D.C. de Waal F.B.M. Young L.J. Oxytocin-dependent consolation behavior in rodents.Science. 2016; 351: 375-378Crossref PubMed Scopus (406) Google Scholar they revealed in 2016 that both male and female prairie voles (but not meadow voles) console their mates and siblings (but not strangers) by allogrooming after seeing them undergo a stressful experience—a behavior requiring oxytocin. "A furry shoulder to cry on," proclaimed the New York Times, as the authors went on to show evidence for emotional contagion and state-matching—hallmarks of empathy. Larry was a strong proponent of diversifying neuroscience research organisms, but he was not averse to using the laboratory mouse in his studies and published some of his most cited research on social memory, social recognition, and maternal care in mice. Still, he wanted to bring molecular genetic tools so commonly deployed in mouse research to the prairie vole. He collaborated with Robert to use optogenetics for the first time in prairie voles5Amadei E.A. Johnson Z.V. Kwon Y.J. Shpiner A.C. Saravanan V. Mays W.D. Ryan S.J. Walum H. Rainnie D.G. Young L.J. Liu R.C. Dynamic corticostriatal activity biases social bonding in monogamous female prairie voles.Nature. 2017; 546: 297-301Crossref PubMed Scopus (74) Google Scholar to bias pair bond formation by stimulating a corticostriatal pathway. He brought in expertise to generate oxytocin receptor knockout and Cre recombinase-expressing voles and produced CRISPR viruses to site-specifically label and manipulate the oxytocin and vasopressin systems. Larry was always at the cutting edge of the mechanistic science of affiliative behavior. Larry's research success propelled him onto ever larger stages where he helped to grow the field of social neuroscience worldwide through his collaborative efforts. As an assistant professor, he headed the Affiliation Collaboratory for the National Science Foundation-funded Center for Behavioral Neuroscience in Atlanta, bringing local behavioral neuroscientists together in conversation about the latest research on prosocial behavior. As a full professor, he founded and directed the National Institute of Mental Health Silvio O. Conte Center for Oxytocin and Social Cognition, bringing together leading researchers using model systems from rodents to non-human primates and humans. He created and directed the Center for Translational Social Neuroscience at Emory and the Center for Social Neural Networks in Tsukuba, Japan. He had one goal: to raise the profile of neurobiological research on social behavior and its translational potential. He was an officer and founding member in the then fledgling Society for Social Neuroscience—serving terms as secretary/treasurer and then as president. He helped organize numerous scientific conferences around the world, most recently in South Korea and Japan. But these trips were not just about the work and the scientists he got to know and inspire; they were sources of fascination for his adventurous spirit, and he always returned with stories to tell along with souvenirs of his travels (including a diverse collection of acquired animal skulls proudly displayed in his office). One of Larry's many gifts was his ability to take a complex problem or dataset and cut straight to the key issues, design the "money experiments," and communicate the story in a simpler light. He was prolific and wrote numerous influential review articles that articulated the implications of his animal research for understanding normal and disordered human social behaviors. To reach an even larger audience, he co-authored a popular book1Young L. Alexander B. The chemistry between us: Love, sex, and the science of attraction. Current, 2012Google Scholar with writer Brian Alexander to tell the stories of scientific discoveries in behavioral neuroendocrinology using the voices of scientists themselves. Robert assigns that book in a freshman seminar at Emory, and when Larry came one year to a meet-the-author session of the course, he amazed students with tales of his experimental findings in lizards and voles. A student later commented, "It is rare to find a book that easily integrates various areas of interest into a cohesive, informative, and understandable narrative, but Dr. Young achieved just that." Until 2019, even Larry did not recognize the global implications of his science. Reverend Patti Ricotta of Life Together International reached out to him that year on a whim to let him know she had been using his research since 2011 to try to persuade certain East African communities to abandon the practice of female genital mutilation. Larry was stunned and delighted. He traveled with Patti to Africa to lay out the scientific facts about the neurochemistry behind pair bonding at conferences in Uganda and Kenya attended by health care professionals, clergy, and tribal leaders. He would always begin his talks—even the ones at regular scientific conferences—by showing a picture of Anne, his own deeply loved pair bonded partner, and that invariably made a connection with audiences hungry to learn how that happens. Reflecting on the experience, Larry noted, "I always intended for my research to benefit humans and human health, but this is an area I would not have predicted could make such a big difference for thousands of people." Back in the lab, Larry's legacy stems—not just from the science he produced—but also the scientific offspring he fostered. He felt privileged to be in a career where creative thinking was rewarded. He acknowledged that no job is 100% fun all the time, but even with grant writing, publishing manuscripts, and administrative duties, he thoroughly loved his career and life and was a role model for his trainees, particularly in work-life balance. He and Anne would host joint lab parties at their home or family cabin, featuring roasted goat, drinks, competitive sports, even more competitive chili cookoffs, and the frequently present bouncy house castle. He was a tireless advocate of his students and gifted them with monogrammed lab coats to memorialize their scientific growth. Larry advised or co-advised 26 PhD students and 19 postdoctoral fellows—the majority of whom have continued in research within the academy. His trainees have helped grow the ranks of those using prairie voles to model mammalian social behavior and its deficits—so much so that Larry's research will continue to inform and inspire for years to come. In fact, before his unexpected passing, he was planning his next grants and collaborations with many of us who will nevertheless continue to carry forward the scientific vision his research has sowed. The scientific community has lost a pillar of social neuroscience research, and we mourn for the discoveries that were yet to come and are now delayed. Just as poignantly, each of us who have known Larry personally feel the hole that has been left behind, which is most acute for his wife of 20 years, Anne, also a neuroscientist and professor at Georgia State University. Anne and Larry were presenters at a scientific conference in Italy in 2002 (their session was on the neurocircuitry of love), and they have been "pair bonded" ever since. Together, they raised five children and were in the beginning stages of planning their retirement. They shared a love of all things outdoors and would spend weekends biking, hiking, and fishing. He and Anne also loved traveling together and had recently become certified scuba divers. Sadly, we will no longer experience the enthusiasm and see that glint in Larry's eyes, accompanied by the little shake of his head when he got excited about something. We will miss the enduring love he had for his family, which in his own words from his book, was "a passion undiminished by his reductionist perspective."