Only one speed per object.
Braddick
O
O
D000818:Animals; D001288:Attention; D006801:Humans; D011601:Psychophysics; D011930:Reaction Time; D012684:Sensory Thresholds; D014785:Vision, Ocular / Q000502:physiology*; D014793:Visual Cortex / Q000502:physiology; D014796:Visual Perception / Q000502:physiology*