Gilles Laurent to receive the 2025 Karl Spencer Lashley Award
The American Philosophical Society is pleased to announce the recipient of the 2025 Karl Spencer Lashley Award, Gilles Laurent, in recognition of his “pioneering studies of information encoding and computation in populations of neurons in the central nervous system.” The award will be presented to Prof. Laurent on April 23, 2026, at the Society’s annual Spring General Meeting.
Gilles Laurent spearheaded neural circuit analysis by demonstrating and analyzing coordinated activity of neurons within circuits that encode odors, determining that odor coding in the brain can be understood incisively by considering patterns of neural activity across the population of encoding neurons, as opposed to the traditional approach of considering the properties of each neuron individually. Importantly, Laurent discovered that the number of patterns that actually occur in ongoing neural activity is small compared to the number of patterns that are possible in principle. This set of unique activity patterns corresponds to the set of odors encoded by the circuit, and together forms a continuous, low-dimensional surface within the set of theoretically possible patterns.
In addition to introducing concepts and methods for studies of neural populations, Laurent pioneered the use of evolutionary adaptations to understand general principles of neural organization. His work spans a variety of species, ranging from locusts to turtles, cuttlefish and lizards. A remarkable illustration is his recent work on sleep dynamics in Australian bearded dragons. Exploiting its unique regularity of sleep, Laurent discovered the existence of rapid-eye-movement (REM) sleep in this lizard (REM sleep is equivalent to vivid dream sleep in humans). Before this work, REM sleep had been found only in mammals and birds, a puzzling observation as birds evolved from reptiles. Laurent’s discovery suggested that REM possibly existed already in the common ancestor of all amniotes. Continuing his work on Australian bearded dragons, Laurent also demonstrated the coordination of activities between both sides of the brain differs dramatically between Slow Wave and REM sleep, with unilateral independence during the former and inter-side competition during the latter Analyzing neural population activity across widespread regions, he showed that the regular switches between REM sleep and non-REM sleep are controlled by a rhythm generator in the brainstem.
William T. Newsome, chair of the Karl Spencer Lashley Committee, notes, “By bridging evolutionary biology with experimentation, theoretical frameworks and analysis of high-dimensional data, Laurent has crafted an innovative and transformative body of work that has decisively shaped modern integrative neuroscience.”
“This award comes to me both as a truly wonderful surprise,” notes Laurent, “and as a source of great pride and joy; great pride to be in such amazing company and great joy to see our work—often based on unusual systems—receive such recognition. I am very grateful to the American Philosophical Society and to the Karl Spencer Lashley Award Committee.”
About Gilles Laurent
Gilles Laurent is Director of the Max Planck Institute for Brain Research in Frankfurt, Germany. He holds a doctorate in veterinary medicine from the Ecole Nationale Vétérinaire de Toulouse and a Ph.D. in Neuroethology from the Université Paul Sabatier. Following postdoctoral work at the University of Cambridge, Laurent was appointed Lawrence Hanson Professor of Biology and Computation & Neural Systems at the California Institute of Technology. He is the recipient of the 2025 Louis-Jeantet Prize for Medicine.
About the Karl Spencer Lashley Award
The Karl Spencer Lashley Award was established in 1957 by a gift from Dr. Lashley, a member of the Society, and a distinguished neuroscientist and neuropsychologist. His entire scientific life was spent in the study of behavior and its neural basis. Dr. Lashley’s famous experiments on the brain mechanisms of learning, memory and intelligence helped inaugurate the modern era of integrative neuroscience, and the Lashley Award recognizes innovative work that continues exploration in the field.
