Living in the head shadow of single-sided deafness
Ears may come in pairs, but that doesn’t mean hearing conditions necessarily come in twos as well.
That’s a good thing, because in many cases hearing loss in one ear can be improved through the other. Single-sided deafness (SSD) is a condition in which a person has lost hearing in one ear, while he or she may have anywhere from normal hearing to profound hearing loss in the other.
We were designed to have two ears for a reason; the brain uses both ears for elevated volume, to pinpoint the direction of a sound and for additional processing power. The California Ear Institute says losing the function in one ear severely limits a person’s hearing on a variety of levels:
The Head Shadow Effect
Patients with SSD often experience a phenomenon called the head shadow effect, in which sounds that originate on the side of the deaf ear are lost to the listener completely. Low-frequency, long-wavelength sounds bend around a person’s head, and are often perceived well even though the deaf ear may be turned in the direction of the sound.
High-frequency, short-wavelength sounds, however, are not as elastic and do not bend around to the side of the good ear. Thus many high-frequency sounds are lost to a person with SSD. Consonant sounds in speech occur as high-frequency sounds, so a person with SSD can often miss a significant amount of surrounding conversation.
There are a number of potential causes of SSD, including:
SSD is often permanent, but is sometimes treatable through the opposite ear. Your audiologist will perform a hearing test on you, and ask you questions to try and identify the cause of your SSD. From there, he or she might recommend one of two hearing aids for you:
Contralateral Routing of Sound (CROS) Hearing Aid: A CROS hearing aid consists of a transmitter, which is placed in the deaf ear, and a receiver, which is placed in the functioning ear. As sounds hit the deaf ear, the transmitter will communicate them to the receiver in the other ear.
Bone-anchored hearing device: Bone-anchored hearing devices are a surgical alternative, in which a titanium screw is anchored in the skull bone behind the deaf ear. A vibrating sound processor is attached externally, which reads sounds and transmits them through the skull bone to the cochlea of the good ear.
Studies show that these types of hearing aids work well for patients with SSD, particularly in reducing the head shadow effect. Contact an audiologist in your area today if you think you may be suffering from hearing loss.