May 10, 2010 -- Children with hearing loss in one ear have lower speech-language scores than siblings with normal hearing, new research shows.
A team of scientists at the Washington University School of Medicine in St. Louis recruited 74 children from the St. Louis region between the ages of 6 and 12 with one-sided hearing loss. Each child was compared to a sibling with normal hearing.
This allowed the researchers to take into account the possible effects of environmental and genetic factors on language skills.
The children with one-sided hearing loss, called unilateral hearing loss, scored worse than their siblings on tests of language comprehension and oral expression. Children with unilateral hearing loss were also more likely than normal-hearing siblings to have received speech-language therapy. There were no differences between children with unilateral hearing loss in the right ear vs. the left ear or with different degrees of severity of hearing loss.
Unilateral Hearing Loss Affects Language Skills
Judith E. C. Lieu, MD, a Washington University professor and ear, nose and throat specialist at St. Louis Children’s Hospital, says in a news release that previous research has suggested children with hearing loss in one ear might experience problems in school.
“Now our study has shown that, on average, children with hearing loss in one ear have poorer oral language scores than children with hearing in both ears,” she says.
The study is published online in advance of its appearance in the June print issue of the journal Pediatrics.
Other factors affecting test scores were family income and maternal education level.
“This study should raise awareness that if children with hearing loss in one ear are having difficulties in speech or reading in school, their hearing may be part of the problem,” Lieu says. “Parents, educators and pediatricians shouldn’t assume that having hearing in one ear means children won’t need additional assistance.”
She suggests that studies in the future should examine whether hearing aids or amplification systems in classrooms would help children with unilateral hearing loss.
“The effect of hearing loss in one ear may be subtle,” she says. “These children may shun large group situations because the noise overwhelms them, and they have a hard time understanding speech.”
Such children could have trouble playing team sports because “they can’t localize sound well and can’t tell who is calling to them,” Lieu says. “For them, listening takes a lot more work, and they may have to put in extra effort.”
It’s possible that hearing loss affects overall educational achievement and even occupational choice, she says.
The researchers write that the common practice of withholding hearing-related accommodations from children with hearing loss in one ear should be reconsidered, that further research is needed, and that parents and educators ought to be told about the negative impact of unilateral hearing loss on oral language skills.
It is estimated that one in 50 per 1,000 school-aged children have hearing loss in one ear, according to the researchers.