A Hearing Test Could Detect Autism in Babies
A new study has found that a hearing test in babies might help to diagnose autism earlier in childhood. As many parents are well aware, the signs and symptoms of autism often don't show until the toddler age or older, and it can be difficult for some children to get properly diagnosed. And, as is the case with many different health conditions, the earlier the diagnosis the better the outcomes might be for the child, because parents and caregivers can adjust to the new condition and get connected with resources and therapies that can help.
So how does a study on hearing tests in babies connect to autism? Well, according to the study that appeared in the Journal of the American Osteopathic Association in January 2019, the study was based on the knowledge that individuals with autism have sensory processing and/or structural changes in their brain that alter how they hear sounds. As the study explains, high-functioning children with ASD have been found to have significantly slower and asymmetric auditory brainstem reflexes, as well as significantly fewer neurons in auditory nuclei.
What does that mean exactly? It means that a lot of children with autism have hearing issues that range from deafness to being extra-sensitive to sounds, which can then cause additional stress, especially if the autism hasn't been diagnosed yet and neither the child nor the parent knows what's going on.
Knowing that those with autism have different auditory (sound) processing, the researchers theorized that doctors could look more closely at hearing tests in babies as a potential early screening tool for autism.
As you may know, all babies already do receive hearing screens, but this study was new in that it thought to use those hearing screens for more than just testing a baby's ear function. Sometime after a baby is born, and before they are discharged from the hospital, they will undergo a mandatory hearing test as part of the routine newborn tests that all babies receive. However, those hearing screens aren't really analyzed deeply or used for anything more than a “pass” or “fail” result. And at times, they can be difficult to carry out, especially if the infant was just born or underwent a C-section, as there may be more fluid in the baby's ears. The point is, the hearing screens are pretty much just used to determine if your baby can hear or not, but nothing more than that and this study hoped to put the hearing screens that are already being done to further use to diagnose autism.
The study's authors proposed using a specific type of testing called acoustic, or stapedial reflex testing, which measures pressure changes in the middle ear of a baby as it responds to different frequencies. How the baby responds can provide doctors with more information about any potential hearing problems that could point to early signs of autism. They suggested using the testing as early as the first week of the baby's life for earlier detection.
Unfortunately, although it is tempting to think testing for autism could be as simple as a hearing test in babies–and hopefully maybe someday it will be–for now, hearing tests may be used as just one step in the diagnostic process. Many children who have autism will have hearing problems, but not all children with hearing problems will also have autism, so a hearing test could only serve as a sign to parents and doctors to keep an eye out for any additional signs that autism may be present. Additionally, hearing screens that show that there could be a hearing problem could have additional benefits if they lead to therapy for the child, as other studies have shown that interventions that focus on vocalizations and auditory training can help improve brainstem responses in children with ASD, as well as behavioral responses.
According to the study, autism is incredibly common in children, with 1 in 36 children (and affecting more boys than girls) having some form of ASD (autism sensory disorder). With autism so common, it is more important than ever to do everything we can to ensure that all individuals with autism get the highest quality of life available, which, in many cases, involves early diagnosis and intervention.