Fear conditioning system

Coulbourn Instruments fear conditioning system was used in conjunction with Freezeframe 4 software (Actimetrics, Wilmette, IL, USA) to deliver tones and shocks and perform unbiased behavioral analysis. Freezing behavior was used as a measure of fear memory strength and was defined as the complete absence of all movement except that required for respiration. At the start of each day, animal cages were transferred from the vivarium facility to a holding room in our lab, and the subjects were given a 30 min acclimation period before removal for experimentation. Fear conditioning and testing were done in four identical sound attenuating chambers, in a room adjacent to the holding room. For three days prior to training, animals were habituated to the experimenters, conditioning chambers, and the training context.

Animals were fear conditioned 21 days post viral infusion. A Coulbourn Instruments fear conditioning system with computer-controlled shockers, USB cameras for video monitoring/video capture, and FreezeFrame Software (Actimetrics) for unbiased behavioral analysis was used to auditory fear condition rats and to test for conditioned fear responses.