{"id":{"repo_id":"cambridge","oai_identifier":"oai:www.repository.cam.ac.uk:1810/370619"},"canonical_url":"https://search.dev.ndltd.org/etd/cambridge/oai:www.repository.cam.ac.uk:1810/370619","repository":{"repo_id":"cambridge","name":"Cambridge University","base_url":"https://api.repository.cam.ac.uk/server/oai/request"},"display":{"title":"An Investigation into Tinnitus in Adult Users of a Cochlear Implant and Methods for Determining Appropriate Sound Textures for Use in Sound Enrichment Tinnitus Therapy","abstract":"Phantom auditory perceptions (tinnitus) are distressing for a significant proportion of individuals with a severe-to-profound hearing loss. The insertion and use of cochlear implants has been widely reported to lessen the impact of tinnitus in such cases; however, a review of the data shows that tinnitus remains troublesome in a significant proportion of those who have undergone cochlear implantation. The efficacy of sound-enrichment therapy, which is widely used as part of tinnitus management protocols in the UK, may be limited because of a negative impact of cochlear implant signal processing on the sounds used. This project expands on the current knowledge base regarding the existence of troublesome tinnitus within the population of individuals with a cochlear implant using questionnaire studies (chapters one and two). In chapter three, a detailed psychoacoustic investigation of the perceptual properties of a sound texture generator tool are undertaken, as the initial stage of creation of sound textures for tinnitus alleviation in implant users. The latter sections of this thesis establish a reliable approach for users of a cochlear implant to identify their most pleasantly perceived sound texture from the discriminable set of sounds. Two paradigms were compared: An ‘absolute’ pleasantness rating task and a forced-choice comparison procedure. Methods <br>The first part of this project uses questionnaires to establish the proportion of individuals within the adult cochlear implant population who are aware and troubled by tinnitus (cross-sectional approach), and to investigate the changes in tinnitus awareness and impact across the cochlear implantation process and first year of use (longitudinal approach). A novel feature of the questionnaires was to include a range of questions to allow tinnitus specific reports to be ranked relative to other areas of difficulty. Following on from this, exploratory investigations into the perceptual properties of bespoke sound therapy stimuli were undertaken, as a step towards development of sound enrichment stimuli. Difference limen were measured for parameters used to create different sounds, allowing creation of a set of discriminable sound textures, used in the final research study of this thesis Results <br>The result show that seventy-five percent of respondents with cochlear implants reported tinnitus awareness, 13% of individuals ranked tinnitus their primary concern, and nearly a third ranked tinnitus in the top two positions. Cochlear implants were typically more beneficial for tinnitus than hearing aids but improvements in reported tinnitus distress that occurred early following implantation were not always sustained at 12-months. When individuals reported a positive effect of implantation there was greater evidence for masking of tinnitus via the implant rather than reversal of maladaptive plasticity; however, the data did not strongly support one mechanism of benefit for tinnitus. In-depth analysis of some of the perceptual properties the generated sound textures were undertaken and compared to the pre-existing literature for deterministic stimuli, for example, it was found that rate discrimination by normal hearing listeners was significantly poorer for complex stochastic modulation envelopes than has been reported previously for the discrimination of sinusoidal amplitude modulation. Computational models of auditory processing were applied to the novel stimuli to determine how the changes in the stochastic envelopes may be represented within the peripheral auditory system e.g. the difference in rate discrimination mentioned above was found to not be due to smearing across auditory filters and/or due to non-perfect comodulation across channels. Whilst the pleasantness rating approach was appealing for the intuitive user interface, participants’ responses were found to be significantly more variable between sessions, compared to the forced choice approach. One concern of the forced choice approach was whether the number of comparisons required to make reliable judgements would become intractable. This was found not to be the case since investigations showed that the influence of each of the generative model parameters on pleasantness ratings were independent of one another. Combined with the use of a mid-point comparison, this meant that reliable measurement of the most pleasantly perceived sound texture was achieved efficiently. This work represents a useful step in the creation of sound therapy stimuli for future research / clinical use. Conclusions <br>Outcomes from the questionnaire studies demonstrate the need to include tinnitus in the consideration of the management of individuals with cochlear implants, as well as those undergoing implantation. The results inform the counselling given to individuals prior to implant regarding possible tinnitus experiences and highlight potential future research directions and the motivation for these. The sound texture generator chosen was used to create a subset of discriminable sounds for CI users potential use as sound enrichment stimuli for tinnitus alleviation. The inclusion of normal-hearing individuals allowed comparison of findings from psychoacoustic analysis to those measured for deterministic stimuli which expands the literature on this topic. An efficient and tractable method for identifying preferred sound textures was identified, which has significant potential for use as a clinical tool to assist tinnitus sufferers to identify the most appropriate sound textures for them","abstract_html":"Phantom auditory perceptions (tinnitus) are distressing for a significant proportion of individuals with a severe-to-profound hearing loss. The insertion and use of cochlear implants has been widely reported to lessen the impact of tinnitus in such cases; however, a review of the data shows that tinnitus remains troublesome in a significant proportion of those who have undergone cochlear implantation. The efficacy of sound-enrichment therapy, which is widely used as part of tinnitus management protocols in the UK, may be limited because of a negative impact of cochlear implant signal processing on the sounds used. This project expands on the current knowledge base regarding the existence of troublesome tinnitus within the population of individuals with a cochlear implant using questionnaire studies (chapters one and two). In chapter three, a detailed psychoacoustic investigation of the perceptual properties of a sound texture generator tool are undertaken, as the initial stage of creation of sound textures for tinnitus alleviation in implant users. The latter sections of this thesis establish a reliable approach for users of a cochlear implant to identify their most pleasantly perceived sound texture from the discriminable set of sounds. Two paradigms were compared: An ‘absolute’ pleasantness rating task and a forced-choice comparison procedure. Methods &lt;br&gt;The first part of this project uses questionnaires to establish the proportion of individuals within the adult cochlear implant population who are aware and troubled by tinnitus (cross-sectional approach), and to investigate the changes in tinnitus awareness and impact across the cochlear implantation process and first year of use (longitudinal approach). A novel feature of the questionnaires was to include a range of questions to allow tinnitus specific reports to be ranked relative to other areas of difficulty. Following on from this, exploratory investigations into the perceptual properties of bespoke sound therapy stimuli were undertaken, as a step towards development of sound enrichment stimuli. Difference limen were measured for parameters used to create different sounds, allowing creation of a set of discriminable sound textures, used in the final research study of this thesis Results &lt;br&gt;The result show that seventy-five percent of respondents with cochlear implants reported tinnitus awareness, 13% of individuals ranked tinnitus their primary concern, and nearly a third ranked tinnitus in the top two positions. Cochlear implants were typically more beneficial for tinnitus than hearing aids but improvements in reported tinnitus distress that occurred early following implantation were not always sustained at 12-months. When individuals reported a positive effect of implantation there was greater evidence for masking of tinnitus via the implant rather than reversal of maladaptive plasticity; however, the data did not strongly support one mechanism of benefit for tinnitus. In-depth analysis of some of the perceptual properties the generated sound textures were undertaken and compared to the pre-existing literature for deterministic stimuli, for example, it was found that rate discrimination by normal hearing listeners was significantly poorer for complex stochastic modulation envelopes than has been reported previously for the discrimination of sinusoidal amplitude modulation. Computational models of auditory processing were applied to the novel stimuli to determine how the changes in the stochastic envelopes may be represented within the peripheral auditory system e.g. the difference in rate discrimination mentioned above was found to not be due to smearing across auditory filters and/or due to non-perfect comodulation across channels. Whilst the pleasantness rating approach was appealing for the intuitive user interface, participants’ responses were found to be significantly more variable between sessions, compared to the forced choice approach. One concern of the forced choice approach was whether the number of comparisons required to make reliable judgements would become intractable. This was found not to be the case since investigations showed that the influence of each of the generative model parameters on pleasantness ratings were independent of one another. Combined with the use of a mid-point comparison, this meant that reliable measurement of the most pleasantly perceived sound texture was achieved efficiently. This work represents a useful step in the creation of sound therapy stimuli for future research / clinical use. Conclusions &lt;br&gt;Outcomes from the questionnaire studies demonstrate the need to include tinnitus in the consideration of the management of individuals with cochlear implants, as well as those undergoing implantation. The results inform the counselling given to individuals prior to implant regarding possible tinnitus experiences and highlight potential future research directions and the motivation for these. The sound texture generator chosen was used to create a subset of discriminable sounds for CI users potential use as sound enrichment stimuli for tinnitus alleviation. The inclusion of normal-hearing individuals allowed comparison of findings from psychoacoustic analysis to those measured for deterministic stimuli which expands the literature on this topic. An efficient and tractable method for identifying preferred sound textures was identified, which has significant potential for use as a clinical tool to assist tinnitus sufferers to identify the most appropriate sound textures for them","abstract_has_math":false,"creators":["Gomersall, Philip"],"institution":"University of Cambridge","degree_name":"Doctor of Philosophy (PhD)","degree_level":"Doctoral","degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Carlyon, Robert","Baguley, David"],"committee_chairs":[],"committee_members":[],"year":2020,"date_issued":"2020-08-16","date_published":"2020-08-16","updated_at":"2026-07-22T22:24:14Z","subjects":["Audiology","Hearing science","Psychoacoustics","Tinnitus"],"languages":["eng"],"rights":[],"rights_urls":["https://apollo8-f-pro.lib.cam.ac.uk/bitstreams/97d0f516-9d54-4c15-9b60-675f2dc803d7/download","https://www.rioxx.net/licenses/all-rights-reserved/"],"identifier_entries":[]},"links":{"outbound_url":"https://doi.org/10.17863/CAM.109987","outbound_label":"DOI","outbound_source":"dc:identifier.doi"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Carlyon, Robert","Baguley, David"]},{"key":"dc:creator","label":"Author","values":["Gomersall, Philip"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.issued","label":"Date","values":["2020-08-16"]},{"key":"dc:publisher.institution","label":"Dc Publisher Institution","values":["University of Cambridge"]},{"key":"dc:relation.isreferencedby.uri","label":"Dc Relation Isreferencedby URI","values":["https://www.repository.cam.ac.uk/handle/1810/370619"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"dc:type.qualificationlevel","label":"Dc Type Qualificationlevel","values":["Doctoral"]},{"key":"dc:type.qualificationname","label":"Dc Type Qualificationname","values":["Doctor of Philosophy (PhD)"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Audiology","Hearing science","Psychoacoustics","Tinnitus"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["https://apollo8-f-pro.lib.cam.ac.uk/bitstreams/97d0f516-9d54-4c15-9b60-675f2dc803d7/download","https://www.rioxx.net/licenses/all-rights-reserved/"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.doi","label":"DOI","values":["https://doi.org/10.17863/CAM.109987"]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://apollo8-f-pro.lib.cam.ac.uk/bitstreams/13d9b22c-9958-46d8-a444-cdb2eec625b9/download"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Phantom auditory perceptions (tinnitus) are distressing for a significant proportion of individuals with a severe-to-profound hearing loss. The insertion and use of cochlear implants has been widely reported to lessen the impact of tinnitus in such cases; however, a review of the data shows that tinnitus remains troublesome in a significant proportion of those who have undergone cochlear implantation. The efficacy of sound-enrichment therapy, which is widely used as part of tinnitus management protocols in the UK, may be limited because of a negative impact of cochlear implant signal processing on the sounds used. This project expands on the current knowledge base regarding the existence of troublesome tinnitus within the population of individuals with a cochlear implant using questionnaire studies (chapters one and two). In chapter three, a detailed psychoacoustic investigation of the perceptual properties of a sound texture generator tool are undertaken, as the initial stage of creation of sound textures for tinnitus alleviation in implant users. The latter sections of this thesis establish a reliable approach for users of a cochlear implant to identify their most pleasantly perceived sound texture from the discriminable set of sounds. Two paradigms were compared: An ‘absolute’ pleasantness rating task and a forced-choice comparison procedure. Methods <br>The first part of this project uses questionnaires to establish the proportion of individuals within the adult cochlear implant population who are aware and troubled by tinnitus (cross-sectional approach), and to investigate the changes in tinnitus awareness and impact across the cochlear implantation process and first year of use (longitudinal approach). A novel feature of the questionnaires was to include a range of questions to allow tinnitus specific reports to be ranked relative to other areas of difficulty. Following on from this, exploratory investigations into the perceptual properties of bespoke sound therapy stimuli were undertaken, as a step towards development of sound enrichment stimuli. Difference limen were measured for parameters used to create different sounds, allowing creation of a set of discriminable sound textures, used in the final research study of this thesis Results <br>The result show that seventy-five percent of respondents with cochlear implants reported tinnitus awareness, 13% of individuals ranked tinnitus their primary concern, and nearly a third ranked tinnitus in the top two positions. Cochlear implants were typically more beneficial for tinnitus than hearing aids but improvements in reported tinnitus distress that occurred early following implantation were not always sustained at 12-months. When individuals reported a positive effect of implantation there was greater evidence for masking of tinnitus via the implant rather than reversal of maladaptive plasticity; however, the data did not strongly support one mechanism of benefit for tinnitus. In-depth analysis of some of the perceptual properties the generated sound textures were undertaken and compared to the pre-existing literature for deterministic stimuli, for example, it was found that rate discrimination by normal hearing listeners was significantly poorer for complex stochastic modulation envelopes than has been reported previously for the discrimination of sinusoidal amplitude modulation. Computational models of auditory processing were applied to the novel stimuli to determine how the changes in the stochastic envelopes may be represented within the peripheral auditory system e.g. the difference in rate discrimination mentioned above was found to not be due to smearing across auditory filters and/or due to non-perfect comodulation across channels. Whilst the pleasantness rating approach was appealing for the intuitive user interface, participants’ responses were found to be significantly more variable between sessions, compared to the forced choice approach. One concern of the forced choice approach was whether the number of comparisons required to make reliable judgements would become intractable. This was found not to be the case since investigations showed that the influence of each of the generative model parameters on pleasantness ratings were independent of one another. Combined with the use of a mid-point comparison, this meant that reliable measurement of the most pleasantly perceived sound texture was achieved efficiently. This work represents a useful step in the creation of sound therapy stimuli for future research / clinical use. Conclusions <br>Outcomes from the questionnaire studies demonstrate the need to include tinnitus in the consideration of the management of individuals with cochlear implants, as well as those undergoing implantation. The results inform the counselling given to individuals prior to implant regarding possible tinnitus experiences and highlight potential future research directions and the motivation for these. The sound texture generator chosen was used to create a subset of discriminable sounds for CI users potential use as sound enrichment stimuli for tinnitus alleviation. The inclusion of normal-hearing individuals allowed comparison of findings from psychoacoustic analysis to those measured for deterministic stimuli which expands the literature on this topic. An efficient and tractable method for identifying preferred sound textures was identified, which has significant potential for use as a clinical tool to assist tinnitus sufferers to identify the most appropriate sound textures for them"]},{"key":"dc:format.checksum.md5","label":"Dc Format Checksum Md5","values":["e38490f524f44a0e977e5f52469f465e","87eda9de84448d1f82354d60eee3eb5f"]},{"key":"dc:title","label":"Title","values":["An Investigation into Tinnitus in Adult Users of a Cochlear Implant and Methods for Determining Appropriate Sound Textures for Use in Sound Enrichment Tinnitus Therapy"]}]}],"canonical_facts":{"dc:contributor.advisor":["Carlyon, Robert","Baguley, David"],"dc:creator":["Gomersall, Philip"],"dc:date.issued":["2020-08-16"],"dc:description.abstract":["Phantom auditory perceptions (tinnitus) are distressing for a significant proportion of individuals with a severe-to-profound hearing loss. The insertion and use of cochlear implants has been widely reported to lessen the impact of tinnitus in such cases; however, a review of the data shows that tinnitus remains troublesome in a significant proportion of those who have undergone cochlear implantation. The efficacy of sound-enrichment therapy, which is widely used as part of tinnitus management protocols in the UK, may be limited because of a negative impact of cochlear implant signal processing on the sounds used. This project expands on the current knowledge base regarding the existence of troublesome tinnitus within the population of individuals with a cochlear implant using questionnaire studies (chapters one and two). In chapter three, a detailed psychoacoustic investigation of the perceptual properties of a sound texture generator tool are undertaken, as the initial stage of creation of sound textures for tinnitus alleviation in implant users. The latter sections of this thesis establish a reliable approach for users of a cochlear implant to identify their most pleasantly perceived sound texture from the discriminable set of sounds. Two paradigms were compared: An ‘absolute’ pleasantness rating task and a forced-choice comparison procedure. Methods <br>The first part of this project uses questionnaires to establish the proportion of individuals within the adult cochlear implant population who are aware and troubled by tinnitus (cross-sectional approach), and to investigate the changes in tinnitus awareness and impact across the cochlear implantation process and first year of use (longitudinal approach). A novel feature of the questionnaires was to include a range of questions to allow tinnitus specific reports to be ranked relative to other areas of difficulty. Following on from this, exploratory investigations into the perceptual properties of bespoke sound therapy stimuli were undertaken, as a step towards development of sound enrichment stimuli. Difference limen were measured for parameters used to create different sounds, allowing creation of a set of discriminable sound textures, used in the final research study of this thesis Results <br>The result show that seventy-five percent of respondents with cochlear implants reported tinnitus awareness, 13% of individuals ranked tinnitus their primary concern, and nearly a third ranked tinnitus in the top two positions. Cochlear implants were typically more beneficial for tinnitus than hearing aids but improvements in reported tinnitus distress that occurred early following implantation were not always sustained at 12-months. When individuals reported a positive effect of implantation there was greater evidence for masking of tinnitus via the implant rather than reversal of maladaptive plasticity; however, the data did not strongly support one mechanism of benefit for tinnitus. In-depth analysis of some of the perceptual properties the generated sound textures were undertaken and compared to the pre-existing literature for deterministic stimuli, for example, it was found that rate discrimination by normal hearing listeners was significantly poorer for complex stochastic modulation envelopes than has been reported previously for the discrimination of sinusoidal amplitude modulation. Computational models of auditory processing were applied to the novel stimuli to determine how the changes in the stochastic envelopes may be represented within the peripheral auditory system e.g. the difference in rate discrimination mentioned above was found to not be due to smearing across auditory filters and/or due to non-perfect comodulation across channels. Whilst the pleasantness rating approach was appealing for the intuitive user interface, participants’ responses were found to be significantly more variable between sessions, compared to the forced choice approach. One concern of the forced choice approach was whether the number of comparisons required to make reliable judgements would become intractable. This was found not to be the case since investigations showed that the influence of each of the generative model parameters on pleasantness ratings were independent of one another. Combined with the use of a mid-point comparison, this meant that reliable measurement of the most pleasantly perceived sound texture was achieved efficiently. This work represents a useful step in the creation of sound therapy stimuli for future research / clinical use. Conclusions <br>Outcomes from the questionnaire studies demonstrate the need to include tinnitus in the consideration of the management of individuals with cochlear implants, as well as those undergoing implantation. The results inform the counselling given to individuals prior to implant regarding possible tinnitus experiences and highlight potential future research directions and the motivation for these. The sound texture generator chosen was used to create a subset of discriminable sounds for CI users potential use as sound enrichment stimuli for tinnitus alleviation. The inclusion of normal-hearing individuals allowed comparison of findings from psychoacoustic analysis to those measured for deterministic stimuli which expands the literature on this topic. An efficient and tractable method for identifying preferred sound textures was identified, which has significant potential for use as a clinical tool to assist tinnitus sufferers to identify the most appropriate sound textures for them"],"dc:format.checksum.md5":["e38490f524f44a0e977e5f52469f465e","87eda9de84448d1f82354d60eee3eb5f"],"dc:identifier.doi":["https://doi.org/10.17863/CAM.109987"],"dc:identifier.uri":["https://apollo8-f-pro.lib.cam.ac.uk/bitstreams/13d9b22c-9958-46d8-a444-cdb2eec625b9/download"],"dc:language":["eng"],"dc:publisher.institution":["University of Cambridge"],"dc:relation.isreferencedby.uri":["https://www.repository.cam.ac.uk/handle/1810/370619"],"dc:rights":["https://apollo8-f-pro.lib.cam.ac.uk/bitstreams/97d0f516-9d54-4c15-9b60-675f2dc803d7/download","https://www.rioxx.net/licenses/all-rights-reserved/"],"dc:subject":["Audiology","Hearing science","Psychoacoustics","Tinnitus"],"dc:title":["An Investigation into Tinnitus in Adult Users of a Cochlear Implant and Methods for Determining Appropriate Sound Textures for Use in Sound Enrichment Tinnitus Therapy"],"dc:type":["Thesis"],"dc:type.qualificationlevel":["Doctoral"],"dc:type.qualificationname":["Doctor of Philosophy (PhD)"]},"updated_at":"2026-07-22T22:24:14Z"}