 Not much is known about how intrinsic timescales, which characterize the dynamics of endogenous fluctuations in neural activity, changed during cognitive tasks. Here, the authors show that intrinsic timescales of neural activity in the primate visual cortex changed during spatial attention. Experimental data were best explained by a network model in which timescales arise from spatially arranged connectivity. This article was authored by Roxana Serrati, Yang Liangcha, Nicholas A. Steinmetz, and others.