The “head-shadow” effect is one of several extreme disadvantages that people with a deaf (or nearly deaf) ear experience.  Sound which originates from the direction of the deaf ear must travel around the head to the better hearing ear in order to be heard.  The path of sound as it travels over the head may attenuate low pitch sounds by as much as 6.4dB to as much as 20dB for high pitch sounds. Therefore, you could imagine that one strategically placed high frequency weighted word in a sentence such as “missed” could easily lead to a spicy conversation.

  One manufacturer we have found, Phonak, has a very good solution to this call a wireless “CROS”.  In a CROS system, a transmitter placed behind or inside the poorer ear picks up sound and transmits it wirelessly to a receiver either  behind or inside the better hearing ear.  If needed, the receiving device may also act as a hearing aid if there is hearing impairment in the better ear.

  Whereas several disadvantages to single sided deafness (SSD) still remain, one very positive result is an elimination of the head-shadow effect.  The benefit for our clients has been clear as so far all of our SSD cases that have experienced both one hearing aid and a CROS fitting, have opted for the CROS system.

Illustration and some content provided courtesy of Phonak