摘要Background:Profoundly deaf children beyond 5 years of age and deaf adults with no prior access to hearing have limited options to learn oral speech.They rely mainly on sign language for communication.This is because,in the absence of hearing,the brain of a deaf person is not able to process any feedback of its own speech efforts.Method:We have developed a novel assistive technology that provides visual feedback of speech efforts to the brain of a deaf person learning to speak on a smart phone or computer,in the absence of auditory feedback.We propose that a deaf person with compensatory heightened visual processing skills,should be able to use this visual feedback to develop speech.Results:The first prototype of our novel assistive technology was used on 72 deaf persons(children and adults)attending deaf schools in Delhi.They progressed from speaking no sounds to about 18 sounds in 6 months.Conclusion:Assistive technology using sensory substitution is a promising new approach to help deaf children and adults develop oral speech using visual feedback.More research needs to be carried out in developing this technology further.