When Nichole just had one CI and one hearing aid, she didn't do that well locating the source of sounds. And if she turned off either the CI or the hearing aid, she of course did even worse. We were curious if having two CIs had any impact on her sound localization ability.
This past weekend, the whole family played a game with Nichole - "Find the portable phone". Our portable phone has a button on the base station that causes the handset to start beeping, allowing you to find where it was last put down.
We had Nichole stay in the kitchen, then one of us would go either in the basement, or upstairs, and hide the phone. We then started the phone beeping and Nichole had to use her bilateral CIs to locate the handset.
We were amazed at how well she did. In all but one or two cases, she would zero in on the hiding place fairly quickly. Even when we hit the phone in cabinets and containers. She would walk into a room, turn her head left and right, then head off in the direction of the sound. Once, when I had hidden the phone in the ceiling of our basement (can't make things too easy for her :-), Nichole navigated herself to a spot directly below the phone, and was going crazy because she couldn't find the phone on the floor, or on the nearby shelf. Then, she looked up and noticed the open ceiling tile, and the phone. From then on , when she couldn't find the phone, but knew she was in the right area, she would tip her head to the side (one ear up, one ear down), in order to determine if the sound was above or below her.
So besides the improvement in basic hearing, understanding speech and having a "backup" ear in the event one stopped working (or the FM in her case) , we can add sound localization as another benefit of going bilateral! And that is only about 3 and a half weeks post activation!