title: Effect of conditioned stimulus intensity on visually conditioned heart rate change in the pigeon: a sensitization mechanism.
mesh_terms: D000818:Animals; D010856:Columbidae; D003214:Conditioning, Classical / Q000502:physiology*; D003463:Cues; D005260:Female; D006339:Heart Rate; D008297:Male; D010146:Pain; D010775:Photic Stimulation