All fear conditioning took place in Med Associates conditioning chambers (28 × 21 × 21 cm; Lafayette Instrument Co.; Lafayette, IN) that were controlled through Med Associates Video Freeze software, as described previously (Zelikowsky et al., 2013 (link)). The conditioning chambers were configured into 3 distinct contexts: Context A, Context B, and Context C. Footshocks were delivered to the animals through Med Associates shock scramblers in each conditioning chamber (ENV 414-S). Conditioning sessions were recorded by near infrared cameras. Freezing behavior was analyzed via Med Associates Video Freeze software (Zelikowsky et al., 2013 (link)).
Context A consisted of a flat grid floor, windex odor, and white light illumination. Animals were transported to Context A in their homecages, which were mounted on a hanging rack. Context B consisted of an alternating thick and thin grid floor, acetic acid odor, red light illumination, and an A-frame insert. Animals were transported to Context B in a novel, large plastic box. Context C consisted of a white plastic floor, simple green odor, red light illumination, and a white plastic insert. Animals were transported to Context C in a plastic cage with fresh bedding.
Context A consisted of a flat grid floor, windex odor, and white light illumination. Animals were transported to Context A in their homecages, which were mounted on a hanging rack. Context B consisted of an alternating thick and thin grid floor, acetic acid odor, red light illumination, and an A-frame insert. Animals were transported to Context B in a novel, large plastic box. Context C consisted of a white plastic floor, simple green odor, red light illumination, and a white plastic insert. Animals were transported to Context C in a plastic cage with fresh bedding.
