Multiple studies have concluded that varying degrees of hearing loss in adults can lead to serious complications such as cognitive decline, but some risks are even higher for the youngest members of the hard of hearing community. Though deafness in children has already been linked to changes in how their brain processes sound later on, a new study has shown even mild to moderate hearing loss may result in similar changes. With 3 out of every 1000 children born with hearing loss, researchers from the University of Cambridge believe this new information may change the way babies are screened for hearing loss, a time where early detection and intervention are so critical, and how healthcare providers handle mild-to-moderate hearing loss in children.
In adults, hearing loss can result in a reduced quality of life and changes to how your brain processes sound or understand speech and language. This is due to the brain having to overcompensate for its reduced hearing capability, taking important processing power from other areas such as high-level thinking. As the brain adjusts, studies have shown people with untreated hearing loss have less gray matter density in the auditory areas of the brain and show less brain activity when listening to complex sentences.
For children, the effect on the brain can be even more severe. The brain is developing at a rapid rate during adolescence, with auditory stimuli being a critical component of that development. Hearing loss in children may result in diminished language acquisition, poor social and emotional skills, reduced academic achievement, and understanding speech. Without the proper auditory stimulation, the brain will adjust the way it operates in life-changing ways.
Led by Dr. Lorna Halliday of the Cognition and Brain Sciences Unit, the team at the University of Cambridge used an electroencephalogram (EEG) to measure brain responses in 46 children who have been diagnosed with permanent, or mild-to-moderate, hearing loss while they were exposed to auditory stimulation. After dividing the children into two groups, younger (aged 8-12) and older (aged 12-16), the team had found that the younger group showed relatively normal brain responses to sound, similar to those with healthy hearing, while the older group showed smaller brain responses. To confirm these findings, researchers re-tested the younger subset six years later, concluding that as they aged, their brain responses changed even though their hearing loss had not worsened. This suggests a “functional reorganization” had occurred instead, changing the way the brain allocates resources and processes sound over time.
These findings are critically important when addressing the risks of mild hearing loss in children, shining a light on the importance of comprehensive screenings. “Current screening programs for newborn babies are good at picking up moderate-to-profound levels of hearing loss, but not at detecting mild hearing loss.” explains Dr. Halliday, “This means that children with mild hearing impairment might not be detected until later in childhood, if at all.”
If you believe you or your child may be suffering from mild-to-moderate hearing loss, seek the medical advice of a hearing health professional and a comprehensive hearing evaluation.