"Thirty human Ss were presented with a light-shock conditioning sequence, half under avoidance and half under nonavoidance conditions. Avoidance conditioning was significantly inferior to nonavoidance conditioning. Avoidance Ss show relatively prolonged extinction curves. This is consistent with experimental data on resistance to extinction following massed partial reinforcement training." (PsycINFO Database Record (c) 2006 APA, all rights reserved)