Middle Latency Responses to Optimized Chirps in Adult Cochlear Implant Users

Abstract

Cochlear implant (CI) outcomes can be assessed using objective measures that reflect the integrity of the auditory pathway. One such measure is the middle latency response (MLR), which can provide valuable information for clinicians.Traditional stimuli for evoking MLRs, that is, clicks or tone bursts, do not stimulate all parts of the cochlea simultaneously, whereas chirp stimuli compensate for the cochlear neural delay and, therefore, produce more synchronous responses from the different neural elements of the cochlea. The purpose of the present study was to determine whether chirp stimuli can elicit reliable MLRs in CI users and whether those responses correlate with clinical outcomes and with deprivation-related factors.We presented 2,000 free-field optimized chirp stimuli to CI and control participants while their electroencephalography (EEG) was being recorded.Twenty-four adult CI users and 24 matched normal-hearing (NH) individuals (age range from 18 to 63 years) participated in this study.The EEG was recorded from 64 active electrodes placed on the scalp. EEG signals were processed using EEGLAB and ERPLAB toolboxes. We characterized the latencies and amplitudes of the different MLR components in both groups.Chirp stimuli reliably evoked qualitatively similar MLRs across all NH and CI participants with a couple of differences observed between the NH and CI group. Among the different MLR components, the Na latency was significantly shorter for the CI group. A significant amplitude difference was also found between groups for the Pa–Nb complex, with higher amplitudes observed in the NH group. Finally, there were no significant correlations between MLR latencies (or amplitudes) and clinical outcomes or deprivation-related measures.Free-field–presented optimized chirp stimuli were shown to evoke measurable and reliable MLRs in CI users. In this experiment, the MLR morphology in CI users was similar to those observed in NH participants. Even though we did not replicate here a significant relationship between MLR and speech perception measures, we were able to successfully collect acoustically evoked MLRs, which could constitute an important supplemental measure to the standard behavioral tests presently being used in postoperative clinical evaluation settings.

Exploring neurocognitive factors and brain activation in adult cochlear implant recipients associated with speech perception outcomes—A scoping review

“…Twenty-two studies were excluded based on population criteria, studies testing children and adults with prelingual onset of hearing loss (El-Kashlan et al, 2001;Most and Adi-Bensaid, 2001;Lyxell et al, 2003;Rönnberg, 2003;Middlebrooks et al, 2005;Doucet et al, 2006;Heydebrand et al, 2007;Rouger et al, 2007;Hafter, 2010;Li et al, 2013;Lazard et al, 2014;Bisconti et al, 2016;Anderson et al, 2017;Finke et al, 2017;Miller et al, 2017;Moradi et al, 2017;Purdy et al, 2017;McKee et al, 2018;Verhulst et al, 2018;Winn and Moore, 2018;Lee et al, 2019;Smith et al, 2019). In 22 studies, no neurocognitive measure was present (Meyer et al, 2000;Vitevitch et al, 2000;Wable et al, 2000;Giraud and Truy, 2002;Lachs et al, 2002;Lonka et al, 2004;Kelly et al, 2005;Debener et al, 2008;Tremblay et al, 2010;Winn et al, 2013;Moberly et al, 2014;Turgeon et al, 2014;Ramos-Miguel et al, 2015;Collett et al, 2016;Purdy and Kelly, 2016;Sterling Wilkinson Sheffield et al, 2016;Harris et al, 2017;Alemi and Lehmann,...…”

“…Twenty-two studies were excluded based on population criteria, studies testing children and adults with prelingual onset of hearing loss ( El-Kashlan et al, 2001 ; Most and Adi-Bensaid, 2001 ; Lyxell et al, 2003 ; Rönnberg, 2003 ; Middlebrooks et al, 2005 ; Doucet et al, 2006 ; Heydebrand et al, 2007 ; Rouger et al, 2007 ; Hafter, 2010 ; Li et al, 2013 ; Lazard et al, 2014 ; Bisconti et al, 2016 ; Anderson et al, 2017 ; Finke et al, 2017 ; Miller et al, 2017 ; Moradi et al, 2017 ; Purdy et al, 2017 ; McKee et al, 2018 ; Verhulst et al, 2018 ; Winn and Moore, 2018 ; Lee et al, 2019 ; Smith et al, 2019 ). In 22 studies, no neurocognitive measure was present ( Meyer et al, 2000 ; Vitevitch et al, 2000 ; Wable et al, 2000 ; Giraud and Truy, 2002 ; Lachs et al, 2002 ; Lonka et al, 2004 ; Kelly et al, 2005 ; Debener et al, 2008 ; Tremblay et al, 2010 ; Winn et al, 2013 ; Moberly et al, 2014 ; Turgeon et al, 2014 ; Ramos-Miguel et al, 2015 ; Collett et al, 2016 ; Purdy and Kelly, 2016 ; Sterling Wilkinson Sheffield et al, 2016 ; Harris et al, 2017 ; Alemi and Lehmann, 2019 ; Balkenhol et al, 2020 ; Crowson et al, 2020 ; Naples and Berryhill McCarty, 2020 ; Lee et al, 2021 ). Fifteen reviews were excluded as they did not include an original study ( Wilson et al, 2003 , 2011 ; Mitchell and Maslin, 2007 ; Peterson et al, 2010 ; Aggarwal and Green, 2012 ; Anderson and Kraus, 2013 ; Lazard et al, 2013 ; Anderson and Jenkins, 2015 ; Baskent et al, 2016 ; Pisoni et al, 2016 , ...…”