An improved experimental situation for studying visual psychophysics in the goldfish, with data on discrimination of the vertical.
D000818:Animals; D003216:Conditioning, Operant; D003530:Cyprinidae; D004193:Discrimination Learning; D005556:Form Perception; D006799:Housing, Animal; D009949:Orientation; D011601:Psychophysics; D012054:Reinforcement, Psychology; D014785:Vision, Ocular; D014796:Visual Perception