Subject: Re: [AUDITORY] Finding from Greenwood, 1961 From: "Richard F. Lyon" <dicklyon@xxxxxxxx> Date: Sat, 6 Nov 2021 21:44:05 -0700--000000000000583b9a05d02b87f3 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable The last time I pinged Don Greenwood at <ddg@xxxxxxxx> I got a bounce. Does anyone know if he's still with us? It would be interesting to get his comments on this question. I would address the question in terms of the change of bandwidth with level through that middle region, and see if the described result is explainable by level-dependent auditory filter models. Dick On Sat, Nov 6, 2021 at 9:28 PM Hornsby, Benjamin Wade Young < ben.hornsby@xxxxxxxx> wrote: > Hi All, > > I am hoping to pick the brains of those more knowledgeable about this tha= n > I am. I am reading some classic masking papers with a doctoral student an= d > we have a question about a finding reported by Greenwood (1961). > > > > Greenwood, D. D. (1961). Auditory masking and the critical band. *The > journal of the acoustical society of America*, *33*(4), 484-502. > > > https://asa.scitation.org/doi/abs/10.1121/1.1908699?casa_token=3D5nyI-2IW= fCUAAAAA:F_c_w65ZXWcIQE4SDr-qrEcGTLJ9QUtRChx4B2t4rOAdEv8_PJ3wKhHxvfNCaOwJ0E= jucY_H0J3roQ > > > > In this paper Greenwood examined critical bandwidths using a band widenin= g > masking paradigms to measure =E2=80=9Cmasked audiograms=E2=80=9D as he sy= stematically > widened the bandwidth of a masking noise. In one experiment he looked at > growth of masking for his masked audiograms by systematically increasing > the spectrum level (and overall level) of the various noise bands. He did > this for noise bands that were narrower and wider than the critical > bandwidth. > > > > For noise bandwidths that were *greater* than the critical band he showed > a linear growth of masking for tones centered in the noise band (i.e., > linear in band masking). However, when the noise bandwidth was *less* > than the critical bandwidth, growth of masking showed a =E2=80=9Cjog=E2= =80=9D in the growth > of masking function for tones centered in the narrow noise band. That is > masked threshold appeared to decrease (~3 dB) as noise power increased wh= en > the level of the noise reached what he called a =E2=80=9Ctransition level= =E2=80=9D of > around 50 dB sensation level. However, as levels increased above this > =E2=80=9Ctransition=E2=80=9D level, growth of masking again seemed linear= . Figure 6 on p. > 493 of the paper shows the finding I am talking about. > > > > It would not be the first time I misinterpreted an older (and newer) pape= r > so I am probably just missing something. However, I was not familiar with > this finding and wondered if others were aware of it and had thoughts on > why it occurred. > > > > Thanks, > > > > Ben > --000000000000583b9a05d02b87f3 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable <div dir=3D"ltr"><div class=3D"gmail_default" style=3D"font-size:small">The= last time I pinged Don Greenwood at <<a href=3D"mailto:ddg@xxxxxxxx">= ddg@xxxxxxxx</a>> I got a bounce.=C2=A0 Does anyone know if he's s= till with us?=C2=A0 It would be interesting to get his comments on this que= stion.</div><div class=3D"gmail_default" style=3D"font-size:small"><br></di= v><div class=3D"gmail_default" style=3D"font-size:small">I would address th= e question in terms of the change of bandwidth with level through that midd= le region, and see if the=C2=A0described result is=C2=A0explainable=C2=A0by= level-dependent auditory filter models.</div><div class=3D"gmail_default" = style=3D"font-size:small"><br></div><div class=3D"gmail_default" style=3D"f= ont-size:small">Dick</div><div class=3D"gmail_default" style=3D"font-size:s= mall"><br></div></div><div dir=3D"ltr"><div class=3D"gmail_default" style= =3D"font-size:small"><br></div></div><br><div class=3D"gmail_quote"><div di= r=3D"ltr" class=3D"gmail_attr">On Sat, Nov 6, 2021 at 9:28 PM Hornsby, Benj= amin Wade Young <<a href=3D"mailto:ben.hornsby@xxxxxxxx" target=3D"_blan= k">ben.hornsby@xxxxxxxx</a>> wrote:<br></div><blockquote class=3D"gmail_= quote" style=3D"margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,= 204);padding-left:1ex"> <div lang=3D"EN-US"> <div> <p class=3D"MsoNormal">Hi All,<u></u><u></u></p> <p class=3D"MsoNormal">I am hoping to pick the brains of those more knowled= geable about this than I am. I am reading some classic masking papers with = a doctoral student and we have a question about a finding reported by Green= wood (1961). <u></u><u></u></p> <p class=3D"MsoNormal"><span style=3D"font-size:10pt;font-family:Arial,sans= -serif;color:rgb(34,34,34);background:white"><u></u>=C2=A0<u></u></span></p= > <p class=3D"MsoNormal"><span style=3D"font-size:10pt;font-family:Arial,sans= -serif;color:rgb(34,34,34);background:white">Greenwood, D. D. (1961). Audit= ory masking and the critical band.=C2=A0<i>The journal of the acoustical so= ciety of America</i>,=C2=A0<i>33</i>(4), 484-502.<u></u><u></u></span></p> <p class=3D"MsoNormal"><a href=3D"https://asa.scitation.org/doi/abs/10.1121= /1.1908699?casa_token=3D5nyI-2IWfCUAAAAA:F_c_w65ZXWcIQE4SDr-qrEcGTLJ9QUtRCh= x4B2t4rOAdEv8_PJ3wKhHxvfNCaOwJ0EjucY_H0J3roQ" target=3D"_blank">https://asa= .scitation.org/doi/abs/10.1121/1.1908699?casa_token=3D5nyI-2IWfCUAAAAA:F_c_= w65ZXWcIQE4SDr-qrEcGTLJ9QUtRChx4B2t4rOAdEv8_PJ3wKhHxvfNCaOwJ0EjucY_H0J3roQ<= /a><u></u><u></u></p> <p class=3D"MsoNormal"><u></u>=C2=A0<u></u></p> <p class=3D"MsoNormal">In this paper Greenwood examined critical bandwidths= using a band widening masking paradigms to measure =E2=80=9Cmasked audiogr= ams=E2=80=9D as he systematically widened the bandwidth of a masking noise.= =C2=A0 In one experiment he looked at growth of masking for his masked audiograms by systematically increasing the spectrum level = (and overall level) of the various noise bands. He did this for noise bands= that were narrower and wider than the critical bandwidth.<u></u><u></u></p= > <p class=3D"MsoNormal"><u></u>=C2=A0<u></u></p> <p class=3D"MsoNormal">For noise bandwidths that were <b>greater</b> than t= he critical band he showed a linear growth of masking for tones centered in= the noise band (i.e., linear in band masking). However, when the noise ban= dwidth was <b>less</b> than the critical bandwidth, growth of masking showed a =E2=80= =9Cjog=E2=80=9D in the growth of masking function for tones centered in the= narrow noise band. That is masked threshold appeared to decrease (~3 dB) a= s noise power increased when the level of the noise reached what he called a =E2=80=9Ctransition level=E2=80=9D of around 50 d= B sensation level. However, as levels increased above this =E2=80=9Ctransit= ion=E2=80=9D level, growth of masking again seemed linear. Figure 6 on p. 4= 93 of the paper shows the finding I am talking about.<u></u><u></u></p> <p class=3D"MsoNormal"><u></u>=C2=A0<u></u></p> <p class=3D"MsoNormal">It would not be the first time I misinterpreted an o= lder (and newer) paper so I am probably just missing something. However, I = was not familiar with this finding and wondered if others were aware of it = and had thoughts on why it occurred. <u></u><u></u></p> <p class=3D"MsoNormal"><u></u>=C2=A0<u></u></p> <p class=3D"MsoNormal">Thanks,<u></u><u></u></p> <p class=3D"MsoNormal"><u></u>=C2=A0<u></u></p> <p class=3D"MsoNormal">Ben<u></u><u></u></p> </div> </div> </blockquote></div> --000000000000583b9a05d02b87f3--