Appetitive-aversive interactions: Superconditioning of fear by an appetitive cs

Four groups of rats received conditioned suppression training in which a tone and light compound was reinforced with shock. If the light had been previously paired with free food, enhanced fear conditioning accrued to the tone during compound training relative to control groups pre-exposed to the light alone, the light semi-randomly associated with food, or the light unpaired with food. The second experiment replicated the difference in aversive conditioning for the groups receiving the light either paired or unpaired with food. The results are discussed in terms of the functional similarity of a conditioned excitor for food and a conditioned inhibitor for shock.