Denis Aristide Baylor. 30 January 1940—16 March 2022

Abstract

Denis Baylor was one of the leading sensory neuroscientists of the latter part of the twentieth century. His research on the rod and cone photoreceptors of the retina provided a deep understanding of the electrical responses of these cells to light and also of the molecular mechanisms of photo­transduction, whereby light absorption is linked via biochemical reactions within the cell to ion channels in its membrane and thence to cellular membrane voltage changes. He also made major contributions to knowledge of the transmission of these signals to the retina's ganglion cells, which forward information to the brain. Over his career, he invented and/or exploited three important methods for electrophysiological recording: ultra-high-resistance sharp microelectrodes; the suction-pipette technique for photoreceptors; and multielectrode arrays for retina. His research findings have provided important advances in our understanding of visual neuroscience, from the detection of individual photon absorptions by rod photoreceptors, through the underlying molecular mechanisms, to the processing and transmission of these visual signals through the retina. He instilled a love for experimental neuroscience and rigorous scientific investigation into a generation of postdoctoral trainees, students and colleagues. He died of a heart attack on 16 March 2022.