The Braille pattern dots-1246 ( ⠫ ) is a 6-dot braille cell with both top, the middle left, and bottom right dots raised, or an 8-dot braille cell with...

characters. The Braille pattern dots-15 ( ⠑ ) is a 6-dot braille cell with the top left and middle right dots raised, or an 8-dot braille cell with the top...

in vision and involves the macula being stimulated with distorted patterns of dots and the patient identification of where in the visual field this occurs...