The open-source tracking microscope. (Source: Helmholtz Zentrum München and the Technical University of Munich)An open-source tracking microscope developed by German researchers enables concurrent neuro- and behavioral imaging in freely behaving zebrafish larvae. Built with off-the-shelf components, NeuBtracker can be used for neurobehavioral drug screening and for the simultaneous imaging of neuronal activity and behavior of freely swimming fluorescent reporter fish.

Mirror-based tracking avoids moving stages, objectives or light beams to minimize confounding effects on behavior. The system is equipped with two cameras: one to monitor the unrestricted behavior of zebra fish larvae and another fixed on the transparent head to record fluorescent images of the brain.

“This approach makes it possible to observe neuronal activity during unrestrained behavior. We can test the larvae in different environmental conditions and can immediately analyze the effects,” says Prof. Dr. Gil Westmeyer from the Institutes of Biological and Medical Imaging and Developmental Genetics at the Helmholtz Zentrum München as well as the Department of Nuclear Medicine and Munich School of Bioengineering at the Technical University of Munich.

“It is finally possible to see the effects of pharmacological substances on the behavior and the neuronal activity - or other cellular signal processing events - at the same time and across an entire organism. This systemic approach enables us to make new discoveries and we will for example seek to use this device in drug discovery and metabolic research,” Westmeyer adds.