Alejandra A. SILVA-MORENO^* and Francisco J. SANCHEZ-MARIN^†

Centro de Investigaciones en Optica, Loma del Bosque 115 Col Lomas del Campestre, Leon, Gto. 37150, Mexico

(Received December 24, 2002; Accepted April 14, 2003)

Psychophysical experiments were done with hearing and deaf subjects, children and adults to investigate their visual performance when detecting a moving stimulus. Our experiments were done under the Two-Alternative-Forced Choice paradigm, using images with Gaussian noise of known energy as background and moving stimuli of predetermined energies. We confirm the results of better visual performance of deaf adults obtained in previous experiments with static stimuli. In this study, unexpectedly, deaf children also obtained higher performance indexes for relatively high signal energies, when compared to hearing counterparts. Also unexpectedly, in the last experiments, all deaf adults obtained 100% of correct responses while none of the hearing subjects achieved that. Our results suggest a kind of compensation effect in deaf people.

Key words: visual detection, two alternative forced choice, performance index, moving stimulus

^*E-mail address: asilva@foton.cio.mx
^†E-mail address: sanchez@foton.cio.mx