Threshold visibility of frequency gradient patterns.
D005556:Form Perception / Q000502:physiology*; D005584:Fovea Centralis / Q000502:physiology; D006801:Humans; D008297:Male; D008954:Models, Biological; D010364:Pattern Recognition, Visual / Q000502:physiology*; D012160:Retina / Q000502:physiology; D014785:Vision, Ocular