The effect of congenital deafness on duration judgment

Objective: Congenital deafness provides the opportunity to study how atypical sensory and language experiences affect different aspects of information processing, e. g., time perception. Methods: Using two methods of temporal estimation, reproduction (Exp. 1) and production ( Exp. 2), the effect of deafness on duration judgment was investigated within a time domain of a few seconds. We examined 16 congenitally deaf adolescents, aged between 16 and 19 years, and 16 normally hearing subjects, matched for gender and age. In Exp. 1 subjects were asked to reproduce durations from 1 to 5.5 s, whereas in Exp. 2 they produced durations from 1 to 6 s. Results: The results showed that in both experiments, the region of accurate estimation was significantly limited in deaf individuals, compared to normal hearing ones. Deaf adolescents judged accurately only intervals around 3 s, whereas they overestimated standards shorter than 2 s and underestimated those above 3 s. In contrast, controls correctly estimated the majority of standards applied in both experiments, with the exception of underreproduction of intervals longer than 3 s ( Exp. 1). Conclusions: The effect of deafness on the accuracy of duration judgment can be linked to differences in the use of conventional time units, applied strategy as well as cognitive processes such as attention or working memory.