A pretectal command system controls hunting behaviour

Abstract

For many species, hunting is an innate behaviour that is crucial for survival, yet the circuits that control predatory action sequences are poorly understood. We used larval zebrafish to identify a command system that controls hunting. By combining calcium imaging with a virtual hunting assay, we identified a discrete pretectal region that is selectively active when animals initiate hunting. Targeted genetic labelling allowed us to examine the function and morphology of individual cells and identify two classes of pretectal neuron that project to ipsilateral optic tectum or the contralateral tegmentum. Optogenetic stimulation of single neurons of either class was able to induce sustained hunting sequences, in the absence of prey. Furthermore, laser ablation of these neurons impaired prey-catching and prevented induction of hunting by optogenetic stimulation of the anterior-ventral tectum. In sum, we define a specific population of pretectal neurons that functions as a command system to drive predatory behaviour. Key findingsO_LIPretectal neurons are recruited during hunting initiation C_LIO_LIOptogenetic stimulation of single pretectal neurons can induce predatory behaviour C_LIO_LIAblation of pretectal neurons impairs hunting C_LIO_LIPretectal cells comprise a command system controlling hunting behaviour C_LI