Conditioned Responses to Manipulative Procedures Resulting from Exposure to Gamma Radiation

Abstract

The use of gamma radiation as a conditioning stimulus was investigated. Confinement in plastic radiation chambers without actual exposure to radiation caused decreased food and water consumption in rats which had previously experienced eating and drinking during irradiation under similar confinement. Animals deprived of both food and water during exposure did not show the decrement in food and water intake during subsequent confinement in the radiation chamber. Three to five 8-hour exposures (75 r each) produced these effects. In contrast, control animals subjected to a series of confinements without radiation exposure tended to increase their consumption during the later confinement tests. Manipulation and confinement acted as conditioned stimuli to produce reduced consump-tion and ingestion of food and/or water during exposure was necessary to produce the effect.