Exogenous orientation of attention in congenitally deaf individuals

Objective: The goal was to investigate the exogenous orientation of attention in congenitally deaf signers who communicate through Portuguese Sign Language. Method: To study the exogenous orientation of attention, the Posner cueing task was used. In this experimental paradigm, an initial facilitation in the detection of a target at previously attended locations is followed, for longer stimulus onset asynchrony (SOA), by an impairment in speed detection of targets in those locations. This slowing effect is known as inhibition of return (IOR). The sample included 42 participants, 11 deaf subjects with sign language as their first language and 31 hearing subjects with no contact with sign language. Results: Deaf participants detected the targets faster, F(1, 33) = 5.97, p = .02, and more frequently, t(40) = 3.30, p = .002, than the hearing subjects. Also, IOR initiated and ended earlier for the deaf than for the hearing subjects, least significant difference (LSD) test, respectively, at 400 ms, p = .001. p = .97, and at 1,600 ms p = .74 vs. p = .006. These results demonstrate that the sample of congenitally deaf subjects presented a different time course in orienting attention. Results suggest that deaf people are quicker and more accurate in orientating attention to peripheral stimuli, and it is argued that deaf people can orient peripheral attention with less effort, engaging and disengaging attention faster than hearing individuals. Conclusions: Findings support the claim that being congenitally deaf leads to compensatory alterations that improve peripheral visual attention.