Differentiation of the intensity of photic stimuli.
D000818:Animals; D002645:Chickens / Q000502:physiology*; D003214:Conditioning, Classical / Q000502:physiology; D004056:Differential Threshold; D004193:Discrimination Learning / Q000502:physiology; D005260:Female; D005502:Food; D008027:Light; D014796:Visual Perception / Q000502:physiology*