Table 1.

Demographic information of the involved blind and sighted subjects.

Group	Gender	Age	Onset age
	(M/F)	Mean ± std.	Mean ± std.
CB	13/7	26.6 ± 5.0	0
EB	20/7	28.9 ± 7.4	8.0 ± 3.0
LB	30/14	30.9 ± 6.5	19.0 ± 5.3
SC	33/17	28.8 ± 7.00	/
Statistical value	χ 2 = 0.63	F = 2.07	F = 164.14
P value	0.889	0.107	<0.001

CB: congenitally blind, EB: early blind, and LB: late blind.