Before revision:  Applying tools from topological data analysis, we present TopoAct, a visual exploration system used to study topological summaries of activation vectors for a single layer as well as the evolution of such summaries across multiple layers.
After revision:  Applying tools from topological data analysis, we present TopoAct, a visual exploration system to study topological summaries of activation vectors for a single layer as well as the evolution of such summaries across multiple layers.