title: Visuomotor transformations underlying hunting behavior in zebrafish.
abstract: Visuomotor circuits filter visual information and determine whether or not to engage downstream motor modules to produce behavioral outputs. However, the circuit mechanisms that mediate and link perception of salient stimuli to execution of an adaptive response are poorly understood. We combined a virtual hunting assay for tethered larval zebrafish with two-photon functional calcium imaging to simultaneously monitor neuronal activity in the optic tectum during naturalistic behavior. Hunting responses showed mixed selectivity for combinations of visual features, specifically stimulus size, speed, and contrast polarity. We identified a subset of tectal neurons with similar highly selective tuning, which show non-linear mixed selectivity for visual features and are likely to mediate the perceptual recognition of prey. By comparing neural dynamics in the optic tectum during response versus non-response trials, we discovered premotor population activity that specifically preceded initiation of hunting behavior and exhibited anatomical localization that correlated with motor variables. In summary, the optic tectum contains non-linear mixed selectivity neurons that are likely to mediate reliable detection of ethologically relevant sensory stimuli. Recruitment of small tectal assemblies appears to link perception to action by providing the premotor commands that release hunting responses. These findings allow us to propose a model circuit for the visuomotor transformations underlying a natural behavior.
authors.affiliation: Department of Molecular and Cellular Biology and Center for Brain Science, Harvard University, Cambridge, MA 02138, USA. Electronic address: i.bianco@ucl.ac.uk.
authors.forename: Isaac H
authors.initials: IH
authors.lastname: Bianco
authors.affiliation: Department of Molecular and Cellular Biology and Center for Brain Science, Harvard University, Cambridge, MA 02138, USA.
authors.forename: Florian
authors.initials: F
authors.lastname: Engert
mesh_terms: D000818:Animals; D015350:Contrast Sensitivity / Q000502:physiology; D009474:Neurons / Q000502:physiology*; D010364:Pattern Recognition, Visual / Q000502:physiology; D010775:Photic Stimulation / Q000379:methods; D011235:Predatory Behavior / Q000502:physiology*; D011597:Psychomotor Performance / Q000502:physiology*; D012858:Size Perception / Q000502:physiology; D013477:Superior Colliculi / Q000166:cytology* / Q000502:physiology; D014796:Visual Perception / Q000502:physiology*; D015027:Zebrafish / Q000502:physiology