George A. Gates,Emeritus Professor of Otolaryngology at the University of Washington, wrote to me about the importance of speech in noise testing for those with hearing loss. This is a test that many audiologists don't get to. If you hear well enough on the pure tone test (beeps at different frequencies) and can pass the first-round word recognition test (airplane, playground, ice cream etc), which will be familiar to anyone with hearing loss -- you're usually sent on your way with assurances that your hearing is fine.
Here's what Dr. Gates wrote:
"My colleagues and I have shown in both the Framingham cohort and the Seattle Adult Change of Thought group that older people who are otherwise cognitively intact and who perform poorly on speech in noise testing (a measure of central auditory function) are 9 times more likely to be diagnosed with Alzheimers in 3-7 year. The attached editorial amplifies these considerations.
"My colleagues and I interpret these findings as showing that speech processing (central auditory function) relies on intact executive function (one aspect of cognition) and that speech processing becomes abnormal BEFORE other cognitive functions. We believe that the earliest clinical sign of AD is poor speech processing in noise and that studies of new therapies ought to incorporate central auditory testing in order to identify people at greater risk."
I assume that this speech processing in noise is measured with hearing aids or cochlear implants, reinforcing the importance of using them, and using them properly.
This interesting -- and useful -- reply was posted on my now defunct blog on my home page katherinebouton.com
I've pasted it here for others to read.
You are right about audiologists not testing speech in background of noise. I speak on a regular basis to audiologists and hearing instrument specialists and always ask by a show of hands how many, routinely, do this speech in noise testing. I am finding that I rarely see more than 10-15% of the professionals in attendance raise their hands.
In my opinion the extra time that speech in noise testing takes is well worth it, considering the additional information it provides over and above routine pure tone hearing testing. The Q-SIN and BKB tests take less than 10 minutes combined to complete and will allow the provider to counsel the client and family in much greater depth as to what can be expected from hearing aids or if hearing aids are even indicated.
Clients who have hearing loss and who cannot complete the more difficult speech in noise test of the two, the Q-SIN, will require, besides hearing aids, auditory training on a computer (such as LACE training www.neurotone.com or ReadmyQuips www.sensesynergy.com ), hearing assistance at home by installing a simple hearing loop for TV (less than $250-$300), a handheld microphone (such as the Pocketalker) or and FM system (such as the Conversor) and hearing loop technology in their House of Worship (For loop information visit www.hearingloop.org ). Many will benefit from joining a hearing loss support group (Hearing Loss Association of America www.hearingloss.org)