Automated Imaging of Visual Recognition Memory in Larval Zebrafish

This protocol describes an assay for measuring visual recognition memory in larval zebrafish using an automated imaging system. Dubbed the “context recognition assay,” this assay measures the responses of larvae to familiar and unfamiliar visual stimuli displayed on an LCD screen beneath the larvae. Larvae at 7 days postfertilization are exposed for 2 h to one of two patterned, colored stimuli. They are then tested for 15 min with either the exposed stimulus (same) or with the other stimulus (different). In testing, larvae spend less time on the edge and are more active in the same condition. The assay is relatively rapid, robust, and can easily be adapted for parametric studies of learning and memory about visual stimuli.