Subject: Re: [AUDITORY] Cochlear Implants - To interleave or not to interleave? From: Alan Kan <alan.kan@xxxxxxxx> Date: Wed, 28 Sep 2022 10:05:40 +0000--_000_ME2PR01MB49642DD11A27D7A907741506CE549ME2PR01MB4964ausp_ Content-Type: text/plain; charset=WINDOWS-1252 Content-Transfer-Encoding: quoted-printable Hi Jan, The classic paper would be by the inventor of CIS. Wilson, B. S., Finley, C. C., Lawson, D. T., Wolford, R. D., Eddington, D. = K., & Rabinowitz, W. M. (1991). Better speech recognition with cochlear imp= lants. Nature, 352(6332), 236-238. https://doi.org/10.1038/352236a0 Otherwise, I think Philip Loizou's paper speaks more to the question you ar= e asking. Loizou, P. C., Stickney, G., Mishra, L., & Assmann, P. (2003). Comparison o= f speech processing strategies used in the Clarion implant processor. Ear a= nd Hearing, 24(1), 12-19. https://doi.org/10.1097/01.AUD.0000052900.42380.5= 0 Regards Alan From: AUDITORY - Research in Auditory Perception <AUDITORY@xxxxxxxx>= On Behalf Of Jan Schnupp Sent: Wednesday, 28 September 2022 6:24 PM To: AUDITORY@xxxxxxxx Subject: [AUDITORY] Cochlear Implants - To interleave or not to interleave? Dear List, it is my understanding that the vast majority of CI sound processors in use= today are still based or inspired more or less on some variant of the Cont= inuous Interleaved Sampling algorithm, and that one of the key assumptions = / design features of the algorithms in use is that having more than one ele= ctrode channel active in any one ear at the same time is to be avoided. Hen= ce "interleaved" sampling: channels take turns to ensure they aren't active= at once. What I am curious to know is: quite how bad would it be if this a= ssumption was violated? Is it necessarily always very bad? And how certain = can we be about how bad it is? Have people run head-to-head comparisons of = strategies with and without strict interleaving? Intuitively, while I see that having multiple channels active at once may e= xacerbate problems with the already relatively poor channel isolation, I al= so think that forcing channels to fire "in turn" constrains the timing of p= ulses in a manner that may preclude independent temporal coding on differen= t channels. Has this potential trade-off been considered? Is there a well f= ounded consensus that the downsides of having the potential of temporal col= lisions of pulses in different channels will necessarily outweigh potential= upsides from having richer temporal patterning across channels? I would be grateful for references / papers / views / perspectives relevant= to this topic. Many thanks! Jan --------------------------------------- Prof Jan Schnupp City University of Hong Kong Dept. of Neuroscience 31 To Yuen Street, Kowloon Tong Hong Kong https://auditoryneuroscience.com<https://auditoryneuroscience.com> http://jan.schnupp.net<http://jan.schnupp.net> --_000_ME2PR01MB49642DD11A27D7A907741506CE549ME2PR01MB4964ausp_ Content-Type: text/html; charset=WINDOWS-1252 Content-Transfer-Encoding: quoted-printable <html xmlns:o=3D"urn:schemas-microsoft-com:office:office" xmlns:w=3D"urn:sc= hemas-microsoft-com:office:word" xmlns:m=3D"http://schemas.microsoft.com/of= fice/2004/12/omml" xmlns=3D"http://www.w3.org/TR/REC-html40"> <head> <meta http-equiv=3D"Content-Type" content=3D"text/html; charset=3Dus-ascii"= > <meta name=3D"Generator" content=3D"Microsoft Word 15 (filtered medium)"> <style><!-- /* Font Definitions */ @xxxxxxxx =09{font-family:"Cambria Math"; =09panose-1:2 4 5 3 5 4 6 3 2 4;} @xxxxxxxx =09{font-family:Calibri; =09panose-1:2 15 5 2 2 2 4 3 2 4;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal =09{margin:0cm; =09margin-bottom:.0001pt; =09font-size:11.0pt; =09font-family:"Calibri",sans-serif;} a:link, span.MsoHyperlink =09{mso-style-priority:99; =09color:blue; =09text-decoration:underline;} a:visited, span.MsoHyperlinkFollowed =09{mso-style-priority:99; =09color:purple; =09text-decoration:underline;} p.msonormal0, li.msonormal0, div.msonormal0 =09{mso-style-name:msonormal; =09mso-margin-top-alt:auto; =09margin-right:0cm; =09mso-margin-bottom-alt:auto; =09margin-left:0cm; =09font-size:11.0pt; =09font-family:"Calibri",sans-serif;} span.EmailStyle18 =09{mso-style-type:personal; =09font-family:"Calibri",sans-serif; =09color:windowtext;} span.EmailStyle20 =09{mso-style-type:personal-compose; =09font-family:"Calibri",sans-serif; =09color:windowtext;} .MsoChpDefault =09{mso-style-type:export-only; =09font-family:"Calibri",sans-serif; =09mso-fareast-language:EN-US;} @xxxxxxxx WordSection1 =09{size:612.0pt 792.0pt; =09margin:72.0pt 72.0pt 72.0pt 72.0pt;} div.WordSection1 =09{page:WordSection1;} --></style> </head> <body lang=3D"EN-AU" link=3D"blue" vlink=3D"purple"> <div class=3D"WordSection1"> <p class=3D"MsoNormal"><span style=3D"mso-fareast-language:EN-US">Hi Jan,<o= :p></o:p></span></p> <p class=3D"MsoNormal"><span style=3D"mso-fareast-language:EN-US"><o:p>&nbs= p;</o:p></span></p> <p class=3D"MsoNormal"><span style=3D"mso-fareast-language:EN-US">The class= ic paper would be by the inventor of CIS. <o:p></o:p></span></p> <p style=3D"margin-left:24.0pt;text-indent:-24.0pt">Wilson, B. S., Finley, = C. C., Lawson, D. T., Wolford, R. D., Eddington, D. K., & Rabinowitz, W= . M. (1991). Better speech recognition with cochlear implants. <i>Nature</i>, <i>352</i>(6332), 236–238. https://doi.org/10.1038/352= 236a0<o:p></o:p></p> <p class=3D"MsoNormal"><span style=3D"mso-fareast-language:EN-US">Otherwise= , I think Philip Loizou’s paper speaks more to the question you are a= sking.<o:p></o:p></span></p> <p style=3D"margin-left:24.0pt;text-indent:-24.0pt">Loizou, P. C., Stickney= , G., Mishra, L., & Assmann, P. (2003). Comparison of speech processing= strategies used in the Clarion implant processor. <i>Ear and Hearing</i>, <i>24</i>(1), 12–19. https://doi.org/10.1097/= 01.AUD.0000052900.42380.50<o:p></o:p></p> <p class=3D"MsoNormal"><span style=3D"mso-fareast-language:EN-US">Regards<o= :p></o:p></span></p> <p class=3D"MsoNormal"><span style=3D"mso-fareast-language:EN-US"><o:p>&nbs= p;</o:p></span></p> <p class=3D"MsoNormal"><span style=3D"mso-fareast-language:EN-US">Alan<o:p>= </o:p></span></p> <p class=3D"MsoNormal"><span style=3D"mso-fareast-language:EN-US"><o:p>&nbs= p;</o:p></span></p> <p class=3D"MsoNormal"><span style=3D"mso-fareast-language:EN-US"><o:p>&nbs= p;</o:p></span></p> <p class=3D"MsoNormal"><span style=3D"mso-fareast-language:EN-US"><o:p>&nbs= p;</o:p></span></p> <p class=3D"MsoNormal"><b><span lang=3D"EN-US">From:</span></b><span lang= =3D"EN-US"> AUDITORY - Research in Auditory Perception <AUDITORY@xxxxxxxx= CGILL.CA> <b>On Behalf Of </b>Jan Schnupp<br> <b>Sent:</b> Wednesday, 28 September 2022 6:24 PM<br> <b>To:</b> AUDITORY@xxxxxxxx<br> <b>Subject:</b> [AUDITORY] Cochlear Implants - To interleave or not to inte= rleave?<o:p></o:p></span></p> <p class=3D"MsoNormal"><o:p> </o:p></p> <div> <p class=3D"MsoNormal">Dear List,<o:p></o:p></p> <div> <p class=3D"MsoNormal"><o:p> </o:p></p> </div> <div> <p class=3D"MsoNormal">it is my understanding that the vast majority of CI = sound processors in use today are still based or inspired more or less = ;on some variant of the Continuous Interleaved Sampling algorithm, and that= one of the key assumptions / design features of the algorithms in use is that having more than one electrode channel ac= tive in any one ear at the same time is to be avoided. Hence "interlea= ved" sampling: channels take turns to ensure they aren't active at onc= e. What I am curious to know is: quite how bad would it be if this assumption was violated? Is it necessarily al= ways very bad? And how certain can we be about how bad it is? Have peo= ple run head-to-head comparisons of strategies with and without strict inte= rleaving? <o:p></o:p></p> </div> <div> <p class=3D"MsoNormal">Intuitively, while I see that having multiple channe= ls active at once may exacerbate problems with the already relatively poor = channel isolation, I also think that forcing channels to fire "in turn= " constrains the timing of pulses in a manner that may preclude independent temporal coding on different channels= . Has this potential trade-off been considered? Is there a well founded con= sensus that the downsides of having the potential of temporal collisions of= pulses in different channels will necessarily outweigh potential upsides from having richer temporal pattern= ing across channels? <o:p></o:p></p> </div> <div> <p class=3D"MsoNormal"><o:p> </o:p></p> </div> <div> <p class=3D"MsoNormal">I would be grateful for references / papers / views = / perspectives relevant to this topic.<o:p></o:p></p> </div> <div> <p class=3D"MsoNormal"><o:p> </o:p></p> </div> <div> <p class=3D"MsoNormal">Many thanks!<o:p></o:p></p> </div> <div> <p class=3D"MsoNormal"><o:p> </o:p></p> </div> <div> <p class=3D"MsoNormal">Jan<o:p></o:p></p> </div> <div> <div> <div> <div> <div> <div> <div> <div> <div> <div> <div> <div> <p class=3D"MsoNormal"><span style=3D"font-size:9.5pt"><o:p> </o:p></s= pan></p> </div> <div> <p class=3D"MsoNormal"><span style=3D"font-size:9.5pt">--------------------= -------------------<o:p></o:p></span></p> </div> <div> <p class=3D"MsoNormal"><span style=3D"font-size:9.5pt">Prof Jan Schnupp<br> City University of Hong Kong<br> Dept. of Neuroscience<o:p></o:p></span></p> </div> <div> <div> <p class=3D"MsoNormal"><span style=3D"font-size:9.5pt">31 To Yuen Street,&n= bsp;<o:p></o:p></span></p> </div> <div> <p class=3D"MsoNormal"><span style=3D"font-size:9.5pt">Kowloon Tong<o:p></o= :p></span></p> </div> <div> <p class=3D"MsoNormal"><span style=3D"font-size:9.5pt">Hong Kong<o:p></o:p>= </span></p> </div> <div> <p class=3D"MsoNormal"><span style=3D"font-size:9.5pt"><o:p> </o:p></s= pan></p> </div> <p class=3D"MsoNormal"><a href=3D"https://auditoryneuroscience.com" target= =3D"_blank">https://auditoryneuroscience.com</a><o:p></o:p></p> </div> <div> <p class=3D"MsoNormal"><a href=3D"http://jan.schnupp.net" target=3D"_blank"= >http://jan.schnupp.net</a><o:p></o:p></p> </div> </div> </div> </div> </div> </div> </div> </div> </div> </div> </div> </div> </div> </div> </body> </html> --_000_ME2PR01MB49642DD11A27D7A907741506CE549ME2PR01MB4964ausp_--