Potential benefits of across-aid communication for bilaterally aided people: listening in a car.

We explored whether transferring signals between two hearing aids could improve speech intelligibility in noise. This was evaluated using a simulated conversation in a car; speech was presented to the right ear and car noise was presented either to the right or both ears. In three cross-aid communication conditions, the noise in the right ear was scaled and subtracted from the noise in the left ear. Speech intelligibility was determined for a group of normally hearing listeners and a group with bilateral hearing loss. The hearing-impaired group had relatively higher intelligibility scores when the car noise was diotic, whereas the normal-hearing group had relatively higher intelligibility scores in the binaural (dichotic) conditions. The cross-aid conditions led to improved intelligibility compared to the reference conditions. The results indicate that the transfer of signals between hearing aids may be of benefit when listening to speech in a car.