Figure 1. Qualitative measure of the illusion.

Rating from the questionnaire separately for congenitally blind (gray bars), late blind (white bars) and blindfolded controls (dark gray bars). Error bars indicate standard errors. Statements #1 and #2 indicate the illusion statements, while the other three statements were used as control statements for suggestibility. While blindfolded participants reported the illusion, congenitally and blind individuals strongly rejected the illusion statements.