On January 8, 2025, neuroscience lost one of its founding fathers, Floyd E. Bloom, MD. Floyd, who helped establish neuroscience as a recognized multidisciplinary field, was President of the Society for Neuroscience (1976–1977), Editor in Chief of Science (1995–2000), President of the American Association for the Advancement of Science (2002–2003), President of the American College of Neuropsychopharmacology (1989) and an ambassador for neuroscience to the broader science community.
After graduating from the Washington University School of Medicine in 1960, Floyd launched his research career as a Research Associate at the NIMH facility at St. Elizabeth’s Hospital using the electrophysiological technique of microiontophoresis to study neurotransmitter function. He then moved to Yale as a postdoctoral fellow and then Assistant and Associate Professor, during which time he co-authored, with Jack Cooper and Bob Roth, the "bible" of neuropharmacology, The Biochemical Basis of Neuropharmacology. In 1968 he returned to Washington, DC to become Chief of the Lab of Neuropharmacology at NIMH, St. Elizabeth's. Floyd's lab at NIMH pioneered a multidisciplinary approach to neural circuitry that combined anatomical, physiological, and pharmacological tools to fully characterize and biochemically code identified brain circuits. In 1971, the year the Society for Neuroscience was founded, he, Barry Hoffer, and George (Bob) Siggins published a trio of articles documenting the anatomy, electrophysiology, and second-messenger impact of noradrenergic synapses between locus-coeruleus axons and cerebellar Purkinje cells. This work helped launch a new paradigm that linked neurotransmitter identity, synaptic function, and neuroanatomy to identified circuits, an approach that would be a dominant force in neuroscience for the next few decades.
Floyd moved to the Salk Institute in 1975 to establish the Arthur Vining Davis Center for Behavioral Neurobiology. The years at Salk established the Bloom Lab as a leading force for interdisciplinary neuroscience. In 1977, Floyd was elected to the National Academy of Sciences, becoming one of its youngest members at 40 years of age. In 1983, Floyd and his team moved down the street to the Scripps Research Institute. With the expansion of space, there was also an expansion of the scientific enterprise, and independent faculty members occupied labs in five areas of focus: cellular neurobiology and neurohistology, neurophysiology, neurochemistry, and behavioral pharmacology, as well as a new emphasis on region-specific gene expression patterns and novel neuropeptides. While at Scripps, Floyd’s role as a scientific statesman expanded further when he became Editor-in-Chief at Science, where he ushered in multiple innovations and expanded the journal’s standing at the apex of scientific publishing.
Floyd won numerous awards throughout his career, including the Walsh McDermott Medal, the Janssen Award in the Basic Sciences, the Pasarow Award in Neuropsychiatry, the Hermann van Helmholtz Award, the Paul Hoch Distinguished Service Award and the Sarnat Award for Mental Health Research. He also was a member of the Royal Swedish Academy of Sciences and the Institute of Medicine (now the National Academy of Medicine), and he received numerous honorary degrees from major universities.
Although Floyd's direct role as an ambassador for science and his scientific accomplishments were exceptional, he was at least as proud of his profound and far-reaching role as a mentor. His impact as a mentor was celebrated in the Bloom Family Tree that several of his prior trainees assembled in 2005. At that time, the Bloom Family Tree extended across four generations that included 1,000 neuroscientists spread across 60 sites in the United States, 17 in Canada, 1 in Mexico, and 45 sites in 15 countries across Europe and Asia, prompting us to declare that the sun never sets on the Bloom Family Tree! Floyd's impact on how we unravel the profound mysteries of the brain will continue to be felt for many years as the next several generations of his scientific offspring take on new and bigger challenges.
We greatly appreciate the editors of The Journal of Neuroscience commemorating Floyd's scientific legacy through this collection of articles that he co-authored in the Journal through the years. Please note that the thesis work of one of the authors of this Introduction (GAJ) is proudly featured in the collection, a direct reflection of Floyd's enduring mentorship.
—Gary Aston-Jones, Stephen L. Foote, and John H. Morrison
Read more about Dr. Bloom's life in the History of Neuroscience in Autobiography.
Below are a selected collection of JNeurosci publications that broadly span Floyd Bloom's influence in the field over his career.
Activity of norepinephrine-containing locus coeruleus neurons in behaving rats anticipates fluctuations in the sleep-waking cycle
G. Aston-Jones and F. E. Bloom
August 1, 1981. 1(8)876–886; https://doi.org/10.1523/JNEUROSCI.01-08-00876.1981
Nonrepinephrine-containing locus coeruleus neurons in behaving rats exhibit pronounced responses to non-noxious environmental stimuli
G. Aston-Jones and F. E. Bloom
August 1, 1981. 1(8)887–900; https://doi.org/10.1523/JNEUROSCI.01-08-00887.1981
The distribution and morphology of opioid peptide immunoreactive neurons in the cerebral cortex of rats
Jacqueline F. McGinty, Derek van der Kooy, and Floyd E. Bloom
April 1, 1984. 4(4)1104–1117; https://doi.org/10.1523/JNEUROSCI.04-04-01104.1984
Characterization of the prodynorphin and proenkephalin neuropeptide systems in rat hippocampus
Charles Chavkin, William J. Shoemaker, Jacqueline F. McGinty, Alejandro Bayon, and Floyd E. Bloom
March 1, 1985. 5(3)808–816; https://doi.org/10.1523/JNEUROSCI.05-03-00808.1985
Induction and habituation of immediate early gene expression in rat brain by acute and repeated restraint stress
Kathleen R. Melia, Andrey E. Ryabinin, Richard Schroeder, Floyd E. Bloom, and Michael C. Wilson
October 1, 1994. 14(10)5929–5938; https://doi.org/10.1523/JNEUROSCI.14-10-05929.1994
Ethanol Self-Administration Restores Withdrawal-Associated Deficiencies in Accumbal Dopamine and 5-Hydroxytryptamine Release in Dependent Rats
Friedbert Weiss, Loren H. Parsons, Gery Schulteis, Petri Hyytiä, Marge T. Lorang, Floyd E. Bloom, and George F. Koob
May 15, 1996. 16(10)3474–3485; https://doi.org/10.1523/JNEUROSCI.16-10-03474.1996
The 5-HT3 Receptor Is Present in Different Subpopulations of GABAergic Neurons in the Rat Telencephalon
Marisela Morales and Floyd E. Bloom
May 1, 1997. 17(9) 157–3167; https://doi.org/10.1523/JNEUROSCI.17-09-03157.1997
Phosphatidylinositol 3-Kinase Is Required for the Expression But Not for the Induction or the Maintenance of Long-Term Potentiation in the Hippocampal CA1 Region
Pietro Paolo Sanna, Maurizio Cammalleri, Fulvia Berton, Cindy Simpson, Robert Lutjens, Floyd E. Bloom, and Walter Francesconi
May 1, 2002. 22(9)3359–3365; https://doi.org/10.1523/JNEUROSCI.22-09-03359.2002