While interest in active avoidance has recently been resurgent, many concerns relating to the nature of this form of learning remain unresolved. By separating stimulus and response acquisition, aversive Pavlovian-instrumental transfer can be used to measure the effect of avoidance learning on threat processing with more control than typical…

We investigated the role of cholinergic neurotransmission in olfactory fear learning. Mice receiving pairings of odor and foot shock displayed fear to the trained odor the following day. Pretraining injections of the nicotinic antagonist mecamylamine had no effect on subsequent freezing, while the muscarinic antagonist scopolamine significantly…