An automated behavioral box to assess forelimb function in rats

Chelsea C. Wong and colleagues at the University of California – San Francisco have developed and shared a design for an open-source behavioral chamber for the measurement of forelimb function in rats.

Forelimb function (reaching, grasping, retrieving, etc) is a common readout of behaviors for studying neural correlates of motor learning, neural plasticity and recovery from injury. One version of the task used commonly to study these behaviors, the Whishaw single-pellet reach-to-grasp task, traditionally requires an experimenter to manually present each pellet and to shape the behavior rats by placing a subsequent pellet only when the rat has relocated to the other end of the cage over multiple trials. Wong et al. developed an open source, low-cost, automated high-throughput version of this task. The behavioral apparatus, constructed out of commercially available acrylic sheets, features a custom built pellet dispenser, cameras and IR detectors for measuring position of a rat and position of a pellet, and an Arduino board to integrate information about the animal with dispensing of the pellet. Code for automation of the task was built in MATLAB and includes a GUI for altering experiment parameters. Data collected can be analyzed using MATLAB, excel, or most other statistical programming languages. The authors provide example data from the device to highlight its potential use for combining this reaching task with chronic electrophysiological recording techniques. The full design is available in their publication in Journal of Neuroscience Methods.