Jan, I’m pretty sure I recall this paper having percentile data:
Morrell, C. H., Gordon-Salant, S., Pearson, J. D., Brant, L. J., & Fozard, J. L. (1996). Age- and gender-specific reference ranges for hearing level and longitudinal changes in hearing level.
Journal of the Acoustical Society of America, 100, 1949-1967.
Sarah Hargus Ferguson, Ph.D., CCC-A
Department of Communication Sciences and Disorders
University of Utah
From: AUDITORY - Research in Auditory Perception [mailto:AUDITORY@xxxxxxxxxxxxxxx]
On Behalf Of Jan Schnupp
Sent: Tuesday, January 26, 2016 7:49 AM
Subject: Re: [AUDITORY] Will I be deaf?
your point that means can be meaningless is well taken. You've probably heard the joke about the statistician with the head in the freezer and the feet in the oven - on average he's comfortable. But it's hard enough to find publications
with population data showing mean or median audiogram values. I'd quite like to see centile distributions but haven't found any. If you know of good data sources, please share them!
In my little demo I try to be clear that there is a great deal of individual variability in teh severity of presbycusis, and I fully accept that the median need not be representative of the mode or of anyone in particular, but if you give
a simulation based on median audiograms at least you will be able to say that there is a 50% chance that your hearing will be this bad or worse - which I think is a fair representation and a compelling one.
Re noise exposure: my reading (mostly Schmiedt, R. A. (2010) The physiology of cochlear presbycusis. In: (Ed.), The aging auditory system, Springer.) suggests that the evidence for links between presbycusis and noise load is actually not
as strong as one might think. There seems to be a large metabolic (stria vascularis) component to presbycusis which is noise exposure independent. But I don't claim to be an authority on this, so if anyone would like to correct me on this, please do.
Re hidden hearing loss - that would be a very interesting one to simulate, but I don't think anyone quite knows how to do that yet. The effect is likely to be very dependent both on sound intensity and on how "cluttered" the signal is (i.e.
how hard is it to disregard background sounds). Still, if anyone has suggestions on how to make demos for that, I'd love to hear about that.
On 26 January 2016 at 14:09, Jont Allen <jontalle@xxxxxxxxxxxx> wrote:
Hi Trevor, and Jan,
There is a serious flaw in this analysis, and this flaw has been repeated over and over in our field.
You cannot, and should not, treat means as meaningful (pun nice, but unintended).
1) Hearing loss, and consonant (phone) perception are poorly correlated (Trevino and Allen, JASA, 2013).
2) Your final hearing loss (HL), while not a good predictor of your speech loss, is a meaningful measure of your
3) HL at the age of 80 depends strongly on you noise exposure over the proceeding 79 years. If your
a carpenter or professional violinist, and you didn't wear ear plugs, then you will have a very sever loss.
If you take careful care of your ears, by wearing earplugs at the drop of a had, when the level goes up
(it is 10 s before the plugs go in for me, and that may be too late).
You do know, I hope, about the C. Liberman and S. Kujawa (Harvard Med school) study and what they now call "Hidden hearing loss."
4) The HL for women and men at the same old age are very different. This I assume, is explained by their
exposure. But I expect someone will disagree. I would love to (briefly) discuss this question.
So take care and you wont hit that average, even at 80.
On 01/26/2016 02:42 AM, Jan Schnupp wrote:
you might find this little demo of old age hearing loss interesting:
If you click on "show background info" you'll see what data this demo is based on and what it does. The average 80 year old hearing is really scarily bad and I secretly hope that my demo is an exaggeration, but it is based on a peer reviewed study Lee and colleagues
which looks well conducted, so unless the population they had access to is somewhat unrepresentative of ... well .. us (clutching at straws here?)... then I guess the answer is probably yes, if you live long enough the odds are 50% or more that your hearing
will get really quite bad at the end.
On 25 January 2016 at 13:47, Trevor Agus <t.agus@xxxxxxxxx <mailto:t.agus@xxxxxxxxx>> wrote:
When encouraging people to be interested in hearing impairment,
I'd like to say "most of us will be deaf". (The more common "1 in
6 adults in the UK..." isn't quite as personal.)
My best guess is that this is almost true, given our long life
expectancy and the increasing risks of presbycusis, but I'd love
to be able to put a figure on it.
Does anyone on the list have the epidemiological ability (and the
data) to estimate what proportion of the adult population (in the
UK or elsewhere) will at some point have a clinically significant
hearing loss at some point?
All the best,
Prof Jan Schnupp
University of Oxford
Dept. of Physiology, Anatomy and Genetics
Sherrington Building - Parks Road
Oxford OX1 3PT - UK