An essential feature of neurons is their ability to centrally integrate information from their dendrites. The activity of astrocytes, in contrast, has been described as mostly uncoordinated across cellular compartments without clear central integration. Here we report conditional integration of calcium signals in astrocytic distal processes at their soma. In the hippocampus of adult mice of both sexes, we found that global astrocytic activity, as recorded with population calcium imaging, reflected past neuronal and behavioral events on a timescale of seconds. Salient past events, indicated by pupil dilations, facilitated the propagation of calcium signals from distal processes to the soma. Centripetal propagation to the soma was reproduced by optogenetic activation of the locus coeruleus, a key regulator of arousal, and reduced by pharmacological inhibition of α1-adrenergic receptors. Together, our results suggest that astrocytes are computational units of the brain that slowly and conditionally integrate calcium signals upon behaviorally relevant events.

神经元的一个基本特征是它们能够集中整合来自树突的信息。相比之下，星形胶质细胞的活动被描述为跨细胞区室大多不协调，没有明确的中央整合。在这里，我们报告了星形胶质细胞体体远端过程中钙信号的条件整合。在成年雌性小鼠的海马体中，我们发现通过群体钙成像记录的整体星形胶质细胞活动反映了过去几秒时间尺度的神经元和行为事件。通过瞳孔扩张表明的过去的显着事件促进了钙信号从远端过程到体细胞的传播。向体的向心传播是通过蓝斑（唤醒的关键调节因子）的光遗传学激活来再现的，并通过α1-肾上腺素能受体的药理学抑制来减少。总之，我们的结果表明星形胶质细胞是大脑的计算单元，可以根据行为相关事件缓慢且有条件地整合钙信号。