Subject: Re: [AUDITORY] Seeking advice on using ANF firing rate to reslove front-back confusion in sound localization model From: Jan Schnupp <000000e042a1ec30-dmarc-request@xxxxxxxx> Date: Wed, 26 Feb 2025 14:26:43 +0800--0000000000005e490d062f05aa9f Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Dear Qin, I do not think your problem is solvable without some kind of assumptions about HRTF and/or cross-frequency integration. I am also confused about the fact that you are looking ant ANF rates and MSO, as MSO is usually thought of as a structure interested in fine timing rather than temporally coarse rates. And presumably, if your current solution can't do front-back, then I assume you can't do top and bottom either? In any event, whether you look at either ILDs or ITDs in any one frequency band, these will only narrow down source directions to one specific cone of confusion. And you cannot do better unless you incorporate at least some knowledge or assumption about what the shapes of these cones are and how they differ for each cue and frequency band, and combine info across frequencies accordingly, in a sense by discounting directions where the solution cones do not intersect and favoring directions where they do. Jan --------------------------------------- Prof Jan Schnupp Gerald Choa Neuroscience Institute The Chinese University of Hong Kong Sha Tin Hong Kong https://auditoryneuroscience.com http://jan.schnupp.net On Wed, 26 Feb 2025 at 13:23, Qin Liu < 000003c563e12bd3-dmarc-request@xxxxxxxx> wrote: > Dear auditory list, > > I am currently working on a project involving sound localization using > firing rates from auditory nerve fibers (ANFs) and the medial superior > olive (MSO). However, I have encountered an issue: I am unable to > distinguish between front and back sound sources using MSO firing rates > alone but only the left-right. > > I am considering whether auditory nerve fiber (ANF) firing rates might > provide a solution, but I am uncertain how to utilize them effectively. F= or > instance, I have experimented with analyzing the positive gradients of AN= F > firing rates but have not yet achieved meaningful results. > > Could anyone suggest an auditory metric derived from binaural signals, AN= F > firing rates, or MSO that could classify front/back sources without relyi= ng > on HRTF template matching? Any insights or alternative approaches would b= e > invaluable to my work. > > Thank you in advance. I sincerely appreciate any guidance you can offer. > > Best regards, > > *Qin Liu* > Doctoral Student > Laboratory of Wave Engineering, =C3=89cole Polytechnique F=C3=A9d=C3=A9ra= le de Lausanne > (EPFL) > Email: qin.liu@xxxxxxxx > > > --0000000000005e490d062f05aa9f Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable <div dir=3D"ltr"><div>Dear Qin,</div><div><br></div><div>I do not think you= r problem is solvable without some kind of assumptions about HRTF and/or cr= oss-frequency integration.</div><div>I am also confused about the fact that= you are looking ant ANF=C2=A0rates and MSO, as MSO is usually thought of a= s a structure interested in fine timing rather than temporally coarse rates= .=C2=A0</div><div><div>And presumably, if your current solution can't d= o front-back, then I assume you can't do top and bottom either?</div></= div><div>In any event, whether you look at either ILDs or ITDs in any one f= requency band, these will only narrow down source directions to one specifi= c cone of confusion.</div><div>And you cannot do better unless you incorpor= ate at least some knowledge or assumption about what the shapes of these co= nes are and how they differ for each cue and frequency band, and combine in= fo across frequencies accordingly, in a sense by discounting directions whe= re the solution cones do not intersect and favoring directions where they d= o.=C2=A0</div><div><br></div><div>Jan</div><div><br></div><div><div dir=3D"= ltr" class=3D"gmail_signature" data-smartmail=3D"gmail_signature"><div dir= =3D"ltr"><div dir=3D"ltr"><div dir=3D"ltr"><div dir=3D"ltr"><div dir=3D"ltr= "><div dir=3D"ltr"><div style=3D"font-size:12.8px"><br></div><div style=3D"= font-size:12.8px">---------------------------------------</div><div style= =3D"font-size:12.8px">Prof Jan Schnupp</div><div style=3D"font-size:12.8px"= >Gerald Choa Neuroscience Institute</div><div style=3D"font-size:12.8px">Th= e Chinese University of Hong Kong</div><div style=3D"font-size:12.8px"><spa= n style=3D"font-size:12.8px">Sha Tin</span></div><div style=3D"font-size:12= .8px"><span style=3D"font-size:12.8px">Hong Kong</span><br></div><div><div = style=3D"font-size:12.8px"><br></div><a href=3D"https://auditoryneuroscienc= e.com" target=3D"_blank">https://auditoryneuroscience.com</a></div><div><a = href=3D"http://jan.schnupp.net" target=3D"_blank">http://jan.schnupp.net<br= ></a></div></div></div></div></div></div></div></div></div><br></div><br><d= iv class=3D"gmail_quote gmail_quote_container"><div dir=3D"ltr" class=3D"gm= ail_attr">On Wed, 26 Feb 2025 at 13:23, Qin Liu <<a href=3D"mailto:00000= 3c563e12bd3-dmarc-request@xxxxxxxx">000003c563e12bd3-dmarc-request@xxxxxxxx= ists.mcgill.ca</a>> wrote:<br></div><blockquote class=3D"gmail_quote" st= yle=3D"margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padd= ing-left:1ex"><div class=3D"msg-3072320491131342088"> <div dir=3D"ltr"> <div id=3D"m_-7395809928694465995divtagdefaultwrapper" dir=3D"ltr" style=3D= "font-size:12pt;color:rgb(0,0,0);font-family:Calibri,Helvetica,sans-serif,E= mojiFont,"Apple Color Emoji","Segoe UI Emoji",NotoColor= Emoji,"Segoe UI Symbol","Android Emoji",EmojiSymbols"> <p>Dear auditory list,</p> <div><br> I am currently working on a project involving sound localization using firi= ng rates from auditory nerve fibers (ANFs) and the medial superior olive (M= SO). However, I have encountered an issue: I am unable to distinguish betwe= en front and back sound sources using MSO firing rates alone but only the left-right.<br> <br> I am considering whether auditory nerve fiber (ANF) firing rates might prov= ide a solution, but I am uncertain how to utilize them effectively. For ins= tance, I have experimented with analyzing the positive gradients of ANF fir= ing rates but have not yet achieved meaningful results.<br> <br> Could anyone suggest an auditory metric derived from binaural signals, ANF = firing rates, or MSO that could classify front/back sources without relying= on HRTF template matching? Any insights or alternative approaches would be= invaluable to my work.<br> <br> Thank you in advance. I sincerely appreciate any guidance you can offer.<br= > <br> Best regards,<br> <br> <b></b><strong>Qin Liu</strong><span style=3D"color:rgba(0,0,0,0.9);font-fa= mily:"PingFang SC",-apple-system,BlinkMacSystemFont,"Segoe U= I",Roboto,Ubuntu,"Helvetica Neue",Helvetica,Arial,"Hira= gino Sans GB","Microsoft YaHei UI","Microsoft YaHei&quo= t;,"Source Han Sans CN",sans-serif;font-size:16px;background-colo= r:rgb(252,252,252)"></span><br style=3D"color:rgba(0,0,0,0.9);font-family:&= quot;PingFang SC",-apple-system,BlinkMacSystemFont,"Segoe UI"= ;,Roboto,Ubuntu,"Helvetica Neue",Helvetica,Arial,"Hiragino S= ans GB","Microsoft YaHei UI","Microsoft YaHei",&qu= ot;Source Han Sans CN",sans-serif;font-size:16px;background-color:rgb(= 252,252,252)"> <span>Doctoral Student</span><span style=3D"color:rgba(0,0,0,0.9);font-fami= ly:"PingFang SC",-apple-system,BlinkMacSystemFont,"Segoe UI&= quot;,Roboto,Ubuntu,"Helvetica Neue",Helvetica,Arial,"Hiragi= no Sans GB","Microsoft YaHei UI","Microsoft YaHei"= ,"Source Han Sans CN",sans-serif;font-size:16px;background-color:= rgb(252,252,252)"></span><br style=3D"color:rgba(0,0,0,0.9);font-family:&qu= ot;PingFang SC",-apple-system,BlinkMacSystemFont,"Segoe UI",= Roboto,Ubuntu,"Helvetica Neue",Helvetica,Arial,"Hiragino San= s GB","Microsoft YaHei UI","Microsoft YaHei","= ;Source Han Sans CN",sans-serif;font-size:16px;background-color:rgb(25= 2,252,252)"> <span style=3D"color:rgba(0,0,0,0.9);font-family:"PingFang SC",-a= pple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Ubuntu,"Hel= vetica Neue",Helvetica,Arial,"Hiragino Sans GB","Micros= oft YaHei UI","Microsoft YaHei","Source Han Sans CN&quo= t;,sans-serif;font-size:16px;background-color:rgb(252,252,252)">Laboratory of Wave Engineering,=C2=A0</span><span style=3D"color:rgba(0,0,0,0.9);font= -family:"PingFang SC",-apple-system,BlinkMacSystemFont,"Sego= e UI",Roboto,Ubuntu,"Helvetica Neue",Helvetica,Arial,"H= iragino Sans GB","Microsoft YaHei UI","Microsoft YaHei&= quot;,"Source Han Sans CN",sans-serif;font-size:16px;background-c= olor:rgb(252,252,252)">=C3=89cole Polytechnique F=C3=A9d=C3=A9rale de Lausanne (EPFL)</span><br style=3D"col= or:rgba(0,0,0,0.9);font-family:"PingFang SC",-apple-system,BlinkM= acSystemFont,"Segoe UI",Roboto,Ubuntu,"Helvetica Neue",= Helvetica,Arial,"Hiragino Sans GB","Microsoft YaHei UI"= ,"Microsoft YaHei","Source Han Sans CN",sans-serif;font= -size:16px;background-color:rgb(252,252,252)"> <span style=3D"color:rgba(0,0,0,0.9);font-family:"PingFang SC",-a= pple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Ubuntu,"Hel= vetica Neue",Helvetica,Arial,"Hiragino Sans GB","Micros= oft YaHei UI","Microsoft YaHei","Source Han Sans CN&quo= t;,sans-serif;font-size:16px;background-color:rgb(252,252,252)">Email: <a href=3D"mailto:qin.liu@xxxxxxxx" target=3D"_blank">qin.liu@xxxxxxxx</a></= span></div> <br> <br> <p></p> </div> </div> </div></blockquote></div> --0000000000005e490d062f05aa9f--