Jc. Stevens et al., TACTILE ACUITY, AGING, AND BRAILLE READING IN LONG-TERM BLINDNESS, Journal of experimental psychology. Applied, 2(2), 1996, pp. 91-106
Tactile acuity came under investigation in 69 blind and 69 age-matched
, sighted adults. Measures comprised thresholds for discriminating gap
s, length (lines), and orientation (along vs. across the finger). Acui
ty of blind and sighted participants' index fingertip declined as a fu
nction of age at the same rate: roughly 1% threshold rise per annum. S
lower braille reading paralleled this decline, as assessed with a tact
ile adaptation of the Tinker-Carver test. From youths to elders, howev
er, blind participants outperformed sighted participants with the fing
ertip but not the lip, a site of commensurate acuity. Experimental tri
als of enlarged braille and development of a tactile Snellen-type char
t for screening of acuity-related difficulty suggest themselves as pro
mising applications.