Soon after we married, I sent my husband for a hearing test. He couldn’t hear me say, “Could you change the baby–he’s poopy!” Strangely, his hearing was found to be perfect. The mystery was never solved.
Fast forward about 40 years. My sweet Richard no longer needs to fear poopy diapers, but he often can’t hear me. The TV is way too loud, IMHO, and he complains that I mumble. You guessed it—hearing loss.
Now for the science. During our first visit to the clinic, we were helped by Ted, a used car…ahem…hearing aid salesman. My eyes were immediately drawn to a strategically placed printout that just happened to be facing us. It was of a study from Johns Hopkins showing that hearing loss may be linked to dementia.
Ted explained how ears work (I didn’t reveal that I already knew!) and claimed hearing primarily occurs in the brain. This isn’t really true, but since the signal from the ears is interpreted by the brain, I decided not to be a brat. I didn’t enlighten him.
Furthermore, he claimed that if hearing loss isn’t treated, one loses the ability to hear. Ever! Because “what you don’t use, you lose.” Hmm, I thought. That should be enough to get anyone to buy expensive aids!
Being a scientist, however, I was skeptical and thought it over. Note the hidden assumption: for this to happen, the hearing-limited person’s family and friends should NEVER shout loud enough so they hear. After all, that WOULD stimulate their brain and prevent the loss. Oops!
Well, what about the study? While Richard’s hearing was being tested, I read the paper. Apparently, scientists began tracking 639 people in 1990-4. A quarter of the subjects already had hearing loss (double the norm, which suggests that they may have been advanced in age).
In 2008, the scientists found that 58 of these people had some dementia. Well, they were now almost 20 years older! They also found that the people who had hearing loss in 1990-1994 were more likely to have dementia in 2008. So, did the hearing loss cause dementia, or were those people older to begin with? This is a MAJOR problem with the study. They don’t say.
Another significant oversight by the scientists is the lack of recognition that the parts of the brain involved in dementia are not the same as the part that interprets sound.
Ted and Richard returned, and Ted began his spiel, complete with scare tactics. Fortunately, because I could read, understand, and critique the science, we didn’t get scared. But we did purchase hearing aids from someone else.