Video freeze v2

Fear conditioning was performed as previously described (Wehner and Radcliffe, 2004 (link)). Briefly, test mice are placed in a fear conditioning chamber (MedAssociates) and allowed to explore the arena for 2 min, after which a loud auditory stimulus (30 s; 90 dB) that co-terminates with a 2 s mild footshock (0.5 mA) is presented to the animal. This is repeated twice more, with a 1 min interval separating the tones/shocks. After 24 hr, animals are returned to the chamber, and its behavior in the context, in a new context, and with the audible tone played in a new context is recorded by a videotracking system (Video Freeze V2.6; MedAssociates) (RRID:SCR_014574). Data are presented as percent of time the mouse is immobile.

Fear conditioning was performed as previously described [25 ]. Training was performed at P44 and testing at P45. Briefly, test mice were placed in a fear conditioning chamber (MedAssociates) and allowed to explore the arena for 3 min, after which a loud auditory stimulus (30 s; 90 dB) that co-terminates with a 2 s mild foot-shock (0.5 mA) is presented to the animal. This is repeated twice, with a 1 min interval separating the tones/shocks. After 24 h, animals are returned to the chamber, and mouse behavior (moments of freezing and moving) when exposed to the same environment (contextual fear-conditioning) and when exposed to a new environment, where the audible tone is played, is recorded by a video-tracking system (Video Freeze V2.6; MedAssociates). Data are presented as percent of time the mouse is immobile.