A novel spherical treadmill apparatus for the head-fixed behaving rat

ANABEL M.M. MIGUELEZ FERNÁNDEZ; ARIEL BURMAN; ALFREDO I. MARTÍNEZ CÁCERES; B. SILVANO ZANUTTO; SERGIO LEW

Congreso; XXIX Congreso Anual de la Sociedad Argentina de Investigación en Neurociencias; 2014

We introduce a novel training apparatus for rodents that allows animals to perform motor responses while being head fixed.This apparatus was developed for the purpose of recording extracellular neuronal activity in the motor cortex of an animal while it performs a motor task.  It consists of a freely rotating spherical treadmill and an iron structure where animals are head fixed.  Once secured to the structure, animals are placed over the treadmill with their limbs on the sphere so they can walk in any direction. Head fixation is achieved by an x-shaped aluminum piece that is surgically implanted on the skull.Movements of the animal are measured as rotations of the spherical treadmill. Sphere speed and rotation direction are detected with a 60fps video camera, using custom designed software. The software also allows a wide control of training parameters and performs data storage for posterior analysis. Here we report training a Long Evans rat in an operant conditioning task where walking on the treadmill after presentation of an auditory stimulus was rewarded with a drop of water.