A single leaflet can integrate signals from a dozen (or more) different neurons. These integrated calcium events can influence communication among the wrapped synapses. #Integration

Key finding: Leaflets envelop synapses, contain ER fragments, and link via gap junctions to form a functional domain. When nearby synapses fire, small calcium rises occur; integrated activity produces larger calcium events. #Synapse

Why now? The finest astrocyte regions at synapses are tiny and hard to image. The team combined volumetric EM (nanoscale) with a custom optical method to capture calcium changes in very small volumes. #Microscopy

Background: Since the 1990s, calcium has been known as astrocytes’ messenger. Calcium signals can trigger the release of transmitters that tune synaptic strength. The ER stores and releases this calcium. #Calcium #ER

Published in Cell (Sep 24, 2025), the study shows astrocytes don’t just modulate one synapse; they coordinate multiple inputs across space and time—active computation, not passive support. #ComputationalBrain

Right panel: a 3D rendering by artist Rémi Greco, built from real data (© Lucas Benoit & Rémi Greco / GIN). Visualization helps reveal how leaflets sit among synapses. #SciArt #3D

Each astrocyte touches several neurons and >100,000 synapses. At the microscopic level, dozens of synapses cluster around a single astrocytic structure called a “leaflet,” which can detect and integrate multiple inputs. #Brain

Astrocytes, the brain’s unexpected conductors.
A Franco-Swiss team shows these glial cells integrate signals from many neurons—a conceptual shift in how we think the brain computes.
#Neuroscience #Astrocytes #Glia #Cell