Voice pitch control ability of hearing persons with or without tactile feedback using a two-dimensional tactile display system

Abstract

It is difficult for the deafblind or the hearing impaired to control the pitch of their voice because they cannot perceive it. In particular, when singing, it is very difficult for them to control their voice pitch because they need to maintain a stable tone. We have developed a voice pitch control system to assist their singing by means of a tactile display. Using this tactile feedback system, we verified in a previous study that two deafblind subjects were able to control the pitch of their voices with as much accuracy as hearing children. By using this tactile feedback system, the correspondence between musical scale and proprioceptive sensation (muscular sensation and so on) of the two subjects was returned to pre-hearing loss levels. They sung using not only tactile feedback but also proprioceptive feedback. In this paper, we investigate the ability of hearing subjects to control the pitch of their voice, without auditory feedback, using our tactile feedback system. Seven hearing participants were examined under two conditions-"without tactile feedback" and "with tactile feedback"-to ascertain their abilities to control their pitch while subjected to masking noise. The results indicated hearing subjects could not sing with accurate pitch using only proprioceptive feedback ("without tactile feedback" condition).