Even in the absence of visual stimuli, assemblies of neurons in the visual system of zebrafish larvae collectively activate. Physically, these assemblies are each localized and together cover the optic tectum along its retinotopic axis. Functionally, less is known about these assemblies, such as how the subnetworks of neurons generate and maintain spontaneous dynamics. To better understand the spontaneous dynamics of neural assemblies in zebrafish larvae optic tectum, we recorded calcium imaging of ~2000 neurons for 1 hour at 15 Hz for 12 fish, and then identified glutamatergic, GABAergic, and cholinergic neurons using immunostaining. We applied a topological data analysis (TDA) to the correlations of assembly neurons during and outside of spontaneous activity. Using Betti curves to summarize the persistent homology, we identified a plausible low-rank structure to the correlations agnostic to spectral analyses. Incorporating TDA into a sliding window analysis allowed us to cluster spontaneous activations into distinct dynamic profiles, ultimately leading us to hypothesize about the role of cholinergic neurons in recruiting and maintaining assembly activity, and more broadly, visual attention.