Tonight the Isham clan braved 2 fantastic hours of rush hour traffic to take Fiona to her first booth testing session. Booth testing is one of the final stages in our journey to prepare Fiona for the Cochlear Implant procedure, and is typically not started until the baby is at least 6 months old. Today Fiona is 6 months and 2 weeks old.
The process is pretty interesting. First you have a soundproof room equipped with speakers and TV flat panels located at strategic locations. Here’s the booth from the outside:
Inside the booth there are speakers immediately to the left and right of the subject, and TV screens located in close proximity to the speakers.
During the test, Eliza sat in the booth with Fiona on her lap, facing the front of the room with the speakers and TVs directly to her left and her right. Our audiologist Lauren sat directly in front of Eliza with various hand puppets to distract Fiona and keep her attention focused forward.
On the outside, Dad stood in the dark with Lauren’s assistant Jenny, looking in through the observation window as the test was underway. The goal of course is to keep hidden from Fiona so she does not get distracted by her dad’s incredibly handsome looks.
Jenny then proceeded to introduce sounds at different locations in the room, looking for a repeatable response from Fiona. Similar in some ways to the ABR test, she would vary the frequency (high pitch to low pitch), volume (75 dB to 95 dB) and location (left or right). (Check out my earlier post on Frequencies of Familiar Sounds for more information on the sound spectrum).
What makes this fun for children are the TV screens. Whenever the child positively responds to the sound (by looking in the direction of the sound), a short flash of a movie displays on the TV nearest to the sound. In this case, it was good ‘ol Nemo.
Here was the display in the control room (to keep dad entertained during the interludes)
This process is called Visual Reinforcement Audiometry. Here’s a short (1 min 30 second) youtube video that shows this process really well.
To score a positive result, Fiona had to respond conclusively twice to the same frequency/volume/location. While she did have a couple “single responses” at high volume and middle frequencies, she did not have a repeatable result. This was as expected given her prior testing – we did not expect a miraculous change. Still, this level of validation is an important milestone to confirm her candidacy for the CI procedure.
Fiona will be booth tested again at least once or twice more before her surgery on March 7th, but this first test was definitely interesting to watch.