Subject: Re: [AUDITORY] National Hearing Test From: "Richard F. Lyon" <dicklyon@xxxxxxxx> Date: Thu, 31 Oct 2013 11:20:53 -0700 List-Archive:<http://lists.mcgill.ca/scripts/wa.exe?LIST=AUDITORY>--001a11c3ee6a98f88b04ea0d827a Content-Type: text/plain; charset=ISO-8859-1 I took the test just now and got the expected result: "slightly below normal range" in both ears (expected, based on previous tests that show somewhat worse than typical hearing for my 61-year age). It would be great if there was better quantification of the result, like dB of SNR degradation relative to normal, rather than just "slightly below normal range". Charles, is there a numeric range associated with these words? It does seem like a pretty effective test of hearing in noise. I presume it's doing an adaptive SNR process, since it would usually give me a relatively easy one after each one where I was pretty much guessing. What I'd like to understand better is exactly how the mechanisms causing threshold elevation also cause degradation of SNR threshold. I presume that the auditory filter bandwidths are wider, and the compression less, with hearing loss. But they're also wider at high levels, and high levels don't cause a degraded SNR threshold, do they? Or maybe they do, in normal hearing, at levels high enough to cause this much bandwidth widening? I've definitely been feeling a degraded ability to deal with conversation in noisy environments (cafes and such), which I understand is correlated with absolute threshold elevation. I'm just not clear on why it's so correlated. Is it understood? Is there a good paper on this? Dick On Wed, Oct 30, 2013 at 9:02 AM, Watson, Charles S. <watson@xxxxxxxx>wrote: > Tom, > I know it is hard to accept that the telephone test works as well as it > does, given the experiences we have all had with a range of signal > qualities for unselected home telephones. However the data showed that > tests taken with over 100 different home phones used by the veterans in our > validation study yielded a similar correlation between the telephone SNR > for 50% correct recognition and average pure-tone thresholds to that > obtained with the carefully selected telephones used to administer the test > in three VA clinics. We have also tested a sample of different phones to > determine the range of distortion and bandwidths, and found them to be > acceptable if speech heard over them was not noticeably distorted. > > Most importantly, the range of absolute levels delivered by various phones > would be quite important if the test measured pure-tone thresholds in the > quiet. The test works because of the insight of Smits and his colleagues > that SNR thresholds can be quite reliable under a range of reproductive > conditions for which absolute thresholds would be virtually meaningless. > > Chuck Watson > > > > -----Original Message----- > From: Tom Brennan [mailto:g_brennantg@xxxxxxxx > Sent: Wednesday, October 30, 2013 6:01 AM > To: Watson, Charles S. > Cc: AUDITORY@xxxxxxxx > Subject: Re: National Hearing Test > > Actually, my comments about telephone service are based on having lived in > Germany for nearly five years and having a number of friends in Europe. I > do believe their telephone system superior to ours. This is especially > true of their cell phone system but is to a lesser degree of their land > lines. > > I wonder if some kind of feedback loop could legally be set up to help > know what kind of phone system a client doing this test i susing. > > Of course, another issue revolves around the fact that most telephones now > allow the user to control the volume of the receiver thus adding another > confo7unding variable to the mix. > > Tom > > > Tom Brennan KD5VIJ, CCC-A/SLP > web page http://titan.sfasu.edu/~g_brennantg/sonicpage.html > --001a11c3ee6a98f88b04ea0d827a Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable <div dir=3D"ltr"><div><div><div>I took the test just now and got the expect= ed result:=A0 "slightly below normal range" in both ears (expecte= d, based on previous tests that show somewhat worse than typical hearing fo= r my 61-year age).<br> <br></div><div>It would be great if there was better quantification of the = result, like=20 dB of SNR degradation relative to normal, rather than just "slightly= =20 below normal range".=A0 Charles, is there a numeric range associated= =20 with these words?<br><br></div>It does seem like a pretty effective test of= hearing in noise.=A0 I presume it's doing an adaptive SNR process, sin= ce it would usually give me a relatively easy one after each one where I wa= s pretty much guessing.<br> <br></div>What I'd like to understand better is exactly how the mechani= sms causing threshold elevation also cause degradation of SNR threshold.=A0= I presume that the auditory filter bandwidths are wider, and the compressi= on less, with hearing loss.=A0 But they're also wider at high levels, a= nd high levels don't cause a degraded SNR threshold, do they?=A0 Or may= be they do, in normal hearing, at levels high enough to cause this much ban= dwidth widening?<br> <br>I've definitely been feeling a degraded ability to deal with conver= sation in noisy environments (cafes and such), which I understand is correl= ated with absolute threshold elevation.=A0 I'm just not clear on why it= 's so correlated.=A0 Is it understood?=A0 Is there a good paper on this= ?<br> <br>Dick<br><br><br><div><br><br></div></div></div><div class=3D"gmail_extr= a"><br><br><div class=3D"gmail_quote">On Wed, Oct 30, 2013 at 9:02 AM, Wats= on, Charles S. <span dir=3D"ltr"><<a href=3D"mailto:watson@xxxxxxxx" = target=3D"_blank">watson@xxxxxxxx</a>></span> wrote:<br> <blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1p= x #ccc solid;padding-left:1ex">Tom,<br> I know it is hard to accept that the telephone test works as well as it doe= s, given the experiences we have all had with a range of signal qualities f= or unselected home telephones. =A0However the data showed that tests taken = with over 100 different home phones used by the veterans in our validation = study yielded a similar correlation between the telephone SNR for 50% corre= ct recognition and average pure-tone thresholds to that obtained with the c= arefully selected telephones used to administer the test in three VA clinic= s. =A0We have also tested a sample of different phones to determine the ran= ge of distortion and bandwidths, and found them to be acceptable if speech = heard over them was not noticeably distorted.<br> <br> Most importantly, the range of absolute levels delivered by various phones = would be quite important if the test measured pure-tone thresholds in the q= uiet. =A0The test works because of the insight of Smits and his colleagues = that SNR thresholds can be quite reliable under a range of reproductive con= ditions for which absolute thresholds would be virtually meaningless.<br> <div class=3D"im HOEnZb"><br> Chuck Watson<br> <br> <br> <br> -----Original Message-----<br> From: Tom Brennan [mailto:<a href=3D"mailto:g_brennantg@xxxxxxxx">g_= brennantg@xxxxxxxx</a>]<br> </div><div class=3D"im HOEnZb">Sent: Wednesday, October 30, 2013 6:01 AM<br= > To: Watson, Charles S.<br> Cc: <a href=3D"mailto:AUDITORY@xxxxxxxx">AUDITORY@xxxxxxxx</a= ><br> Subject: Re: National Hearing Test<br> <br> </div><div class=3D"HOEnZb"><div class=3D"h5">Actually, my comments about t= elephone service are based on having lived in Germany for nearly five years= and having a number of friends in Europe. =A0I do believe their telephone = system superior to ours. =A0This is especially true of their cell phone sys= tem but is to a lesser degree of their land lines.<br> <br> I wonder if some kind of feedback loop could legally be set up to help know= what kind of phone system a client doing this test i susing.<br> <br> Of course, another issue revolves around the fact that most telephones now = allow the user to control the volume of the receiver thus adding another co= nfo7unding variable to the mix.<br> <br> Tom<br> <br> <br> Tom Brennan =A0KD5VIJ, CCC-A/SLP<br> web page <a href=3D"http://titan.sfasu.edu/~g_brennantg/sonicpage.html" tar= get=3D"_blank">http://titan.sfasu.edu/~g_brennantg/sonicpage.html</a><br> </div></div></blockquote></div><br></div> --001a11c3ee6a98f88b04ea0d827a--