A spherical treadmill system to train head-fixed adult rats

Publication date: 1 March 2018
Source:Journal of Neuroscience Methods, Volume 297
Author(s): Anabel M.M. Miguelez Fernández, Ariel Burman, Alfredo I. Martínez Cáceres, Camilo J. Mininni, B. Silvano Zanutto, Sergio E. Lew
BackgroundWhile spherical treadmills are widely used in mouse models, there are only a few experimental setups suitable for adult rats, and none of them include head-fixation.New methodWe introduce a novel spherical treadmill apparatus for head-fixed rats that allows a wide repertory of natural responses. The rat is secured to a frame and placed on a freely rotating sphere. While being head-fixed, it can walk in any direction and perform different motor tasks.Comparison with existing methodsInstead of being air-lifted, which is acceptable for light animals, the treadmill is sustained by three spherical bearings ensuring a smooth rotation in any direction. Movement detection is accomplished using a video camera that registers a dot pattern plotted on the sphere.ResultsLong Evans rats were trained to perform an auditory discrimination task in a Go/No-Go (walking/not-walking) paradigm. Animals were able to successfully discriminate between a 1 kHz and a 8 kHz auditory stimulus and execute the correct response, reaching the learning criterion (80% of correct responses) in approximately 20 training sessions.ConclusionsOur system broadens the possibilities of head-fixation experiments in adult rats making them compatible with spatial navigation on a spherical treadmill.



http://ift.tt/2rVJ3Ou