Populations of cells exhibit a remarkable diversity of behaviors, from the reliable development of multicellular structures to complex coding in neural ensembles. Proper characterization of these phenomena requires an understanding of how dynamics at the single-cell level, when combined with intercellular signaling and environmental cues, give rise to the collective behaviors observed in populations. First, I will present results characterizing the universal signaling dynamics in individual cells of social amoebae, and discuss cell density-dependent transitions to collective, synchronized oscillations. I will then consider population coding in retinal ganglion cells. Recent experiments have shown that the distribution of spiking activity in these cells is poised near a unique critical point where the extensive parts of the entropy and energy are exactly equal. I will demonstrate how such behavior robustly arises due to shared stimulus input. Connections to the statistical mechanics of learning will also be discussed.
David Schwab, Postdoctoral Research Scholar and Lecturer in
Physics, Princeton University, Departments of Physics, Molecular Biology,
and Lewis–Sigler Institute for Integrative Genomics