Tibetan eye chart

The Tibetan eye chart is a tool allegedly developed by Tibetan monks.^{[1][unreliable source?][2][unreliable source?][3][unreliable source?]} According to some authors, it can be used to train the muscles and nerves of the optical system, correcting visual problems.^{[4][unreliable source?][5][unreliable source?]} However, the International Orthoptic Association has found no scientific evidence of the effectiveness of this treatment.^{[6][verification needed]}