Breakthroughs in Language and Literacy in Children Born Deaf

New discoveries help restore hearing in children born with hearing loss.

Posted Feb 25, 2020

When I was growing up in San Diego, there was a brother and sister in my neighborhood whose speech I could not easily understand, because they talked with high-pitched voices and did not pronounce words clearly. My mother told me they spoke this way because they were deaf. In retrospect, because we only saw them on weekends, I also believe they were enrolled in a school for the deaf during the week.

It is noteworthy that these children—and their family—probably represented optimal conditions at that time. Both wore hearing aids on both ears, and their mother encouraged them to play with other children in the neighborhood. And they had horses, which means we were at their house frequently on weekends to feed the horses and play in the barn, which was an interesting place for us to explore. I lived in a semi-rural neighborhood in Southern California, and some of the more affluent families owned horses (my family did not), so I also presume this family was reasonably well-off financially.

Years later, when I was an undergraduate student at San Diego State University learning to be a speech-language pathologist, one of my teaching rotations was at a special school for deaf children in San Diego. In those days, many children born with a severe to profound hearing loss were taken from their families and enrolled in residential schools, where students were exclusively or nearly exclusively children with hearing loss.

I was very impressed with the dedication and commitment from the teachers, students, and their families, who worked so hard together to teach language, most often sign language, to the children and to help them learn to read. I learned the rudiments of a form of sign language, signed exact English (SEE), that included specific hand gestures to highlight grammatical markers such as past tense, auxiliary, and possessive in the hopes of transferring this knowledge to reading ability.

Despite these Herculean efforts, the overwhelming majority of children with severe to profound hearing loss only developed rudimentary reading skills. A landmark study by Hans Furth, published in 1964, reported that the average reading level for deaf people was at the second- or third-grade level and that only about 10 percent ever attained even a fourth-grade reading level[1].

Fast forward more than 25 years, and the reading outcomes for these students remained quite low[2]. In 2009, a commentator on a national report on self-advocacy for deaf people remarked that a decades-long persistence of “The 3rd-grade/4th-grade reading level is a national disgrace.”[3] In essence, there had been no improvements for these children for more than half a century.

Fortunately, recent studies have shown dramatic improvements in speech, language, and literacy outcomes in children born with severe to profound hearing loss. Indeed, many many more children are performing at or above grade level, and some are achieving far beyond the fourth-grade level[4]. To be sure, some reading problems continue[5], but by and large, there have been dramatic improvements and new hope for children born with severe to profound hearing loss.

A key contributor to this progress has been the development of ever-more-effective cochlear implants for children. Ever younger age of implantation along with improved teaching approaches and better hearing aid technology all have contributed to these improved outcomes. The absolute miracle of cochlear implantation cannot be overstated. Otolaryngologists are now able to surgically restore hearing.

Essentially, a cochlear implant involves surgically threading wires through the cochlea, which is shrouded in bone in the temporal region of the skull, and inserting electrodes directly into the auditory nerve. Thereafter, a microphone attached to these wires sends electrical impulses to the auditory centers in the brain via the auditory nerve which can then utilize this information to "hear" spoken language and other important environmental auditory input.

This simple explanation grossly understates the complexity of the operation and the awe-inspiring talents and surgical skills of the otolaryngologists placing the electrodes and the audiologists fine-tuning the auditory input into the processor. One of my colleagues at Vanderbilt University School of Medicine, Dr. Robert Labadie, who is both an accomplished physician and an engineer, is not only one of the nation’s leading surgeons completing cochlear implantation in adults and children but is also an innovative researcher, constantly conducting studies that improve and refine cochlear implantation techniques.

As an example, he and his research team have integrated high-resolution neural scanning methods with preplanning the implant location to reduce the time needed for surgery and to dramatically increase the precision of electrode placement to optimize hearing. Although he is humble about this amazing discovery, Dr. Labadie is literally putting new ears on children with severe to profound hearing loss—and providing their families with new hope that their children will be able to speak, understand what is said to them, and—unlike my neighbors long ago—to learn to read like other children who are born without hearing loss.

In order to put this miracle in perspective, it is also important to mention the work of Dr. Blake Wilson, who, in 2013, won the highest prize for science in the U.S.: the Lasker Prize. In my opinion, he should also be awarded the Nobel prize for his breakthrough discoveries that resulted in effective cochlear implants that have restored the hearing of millions. At the risk of oversimplification, Dr. Wilson developed a procedure for placing the electrodes in an array that essentially harnesses the brain’s natural ability to “fill in” missing information to supplement the relatively weak auditory information being transmitted by the cochlear implant. Prior to his research, cochlear implants worked to only a very limited degree and were not very effective for understanding speech or other complex auditory input.

There is still much to be done, and far too many children born with severe to profound hearing loss continue to have difficulty learning to speak, understanding spoken language, and learning to read. But it is also heartening to reflect on the amazing progress that has been made not only in cochlear implants but also in hearing aid technology and effective teaching. I think back on my neighbors and on the students I taught at the school for deaf, and I can celebrate the fact that we now have many more ways to support the speech, language, and literacy development in children born with severe to profound hearing loss—and that there have been such revolutionary improvements in their lives.

References

[1] Furth, H. G. (1966). A comparison of reading test norms of deaf and hearing children. American Annals of the Deaf, 111(2), 461–462.

[2] Limbrick, L. E. (1991). Reading Development of Deaf Children: Critical Factors Associated with Success. Teaching English to Deaf and Second-Language Students, 9(1), 4-9.

[3] National Consortium of Interpreter Education Centers (2009). The Case for Deaf Self-Advocacy Training and the Need for a National Curriculum on Communication Access. p. 63.

[4] Mayer, C., & Trezek, B. J. (2018). Literacy outcomes in deaf students with cochlear implants: Current state of the knowledge. The Journal of Deaf Studies and Deaf Education, 23(1), 1-16.

[5] Bell, Nicola, Anthony J. Angwin, Wayne J. Wilson, and Wendy L. Arnott. "Reading development in children with cochlear implants who communicate via spoken language: a psycholinguistic investigation." Journal of Speech, Language, and Hearing Research 62, no. 2 (2019): 456-469.