Figure 1.

Expression of platform-mediated avoidance. A, Rats press a bar for sucrose pellets (green quadrant). At tone onset, they gradually step onto the platform to avoid shock (blue quadrant). At tone offset, they gradually return to the bar. B, The position of the rat was defined as the quadrant in which both front paws were located and was scored every 3 s from videos by a trained observer. Position data were scored for days 9 and 10 of conditioning (Trials 1–3, n = 12 rats). The black bar indicates shock. In this and subsequent figures, error bars depict SEM.