Cortical Activity in Subjects With Unilateral Cochlear Implants and Preserved Ipsilateral Residual Hearing and the Evolution of Temporal Cortex Changes in New Recipients of Cochlear Implants.
试验速览
- 阶段
- 不适用
- 状态
- 撤回
- 试验地点
- 2
- 主要终点
- Increase our understanding of why outcomes following a cochlear implant are heterogenous. This information may be used to provide targeted rehabilitation for candidates performing poorly with their implants and minimise rejection of the implant.
研究概览
简要总结
Investigators hope to study patients with 1 cochlear implant and who have had hearing preservation surgery and compare the changes in the brain of these patients with normal hearing patients by doing a scan of the brain when listening to speech. The information investigators collect may help investigators to understand how the brain learns to hear with a cochlear implant and whether it uses the same areas in the brain to listen as in normal hearing patients as well as predict which patients will do well with a cochlear implant as a very specialised operation is needed to insert the cochlear implant in to the ear and is done by very few surgeons in the country. After the operation, patients need several months of teaching to help them learn how to hear through the implant. Having a cochlear implant requires a lot of cooperation and time from the patient and if investigators could understand how the brain learns to hear with a cochlear implant and predict which patients do well and why then we may be able to avoid unnecessary procedures.
详细描述
Cochlear implants are an established treatment for individuals with hearing loss where conventional hearing aids fail to provide appropriate hearing amplification and result in poor speech and language perception.
Although a large proportion of patients with cochlear implants are expected to do well with an implant, there is still uncertainty why some individuals do poorly.
Furthermore investigators have limited knowledge about how the brain interacts with a cochlear implant to process speech. Evidence suggests that the underlying central mechanisms responsible for processing speech using an implant are related to neuroplasticity. That is to say that the brain establishes new cortical networks between the vital auditory centres and the cochlear implant thus enabling processing of speech.
Investigators have recently completed a study comparing the cortical changes that occur in subjects with bilateral cochlear implants to normal hearing controls. In this study both groups of patients were subjected to binaural simultaneous auditory stimuli. Analysis suggests that subjects with bilateral cochlear implants and postlingual hearing loss seem to recruit similar areas of the temporal lobes to process speech as their normal hearing counterparts.
The implant recipients activations were larger and more diffuse but did not differ greatly from those described previously in normal hearing. This study provides a good comparison of hearing using bilateral cochlear implants to that of normal unaided hearing. This study provides a more realistic comparison of cortical activations due to hearing in cochlear implantees and normal hearing subjects. This is in contrast to other studies involving monaural stimulation of a unilateral cochlear implant to monaural stimulation of normal hearing subject with the contralateral normal hearing ear blocked off. Investigators are only aware of one additional study where subjects with bilateral cochlear implants have been compared to normal hearing controls.
研究设计
- 研究类型
- Interventional
- 分配方式
- Non Randomized
- 干预模型
- Parallel
- 主要目的
- Basic Science
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Mature users of unilateral cochlear implants who have natural preserved hearing in the implanted ear
- •Healthy volunteers with normal hearing
- •Right handed
排除标准
- •Individuals with neurological or psychiatric illness
- •Patients involved in additional drug trials
- •Pregnant or breast feeding women
- •Left-handed subjects
研究组 & 干预措施
unilateral cochlear implants
Study Group
PET scans for the mature patients with unilateral cochlear implants and preserved hearing
4 states and each state will be repeated 3 times Cochlear implant only Residual hearing only Combination of implant and residual hearing No auditory stimulation
干预措施: cochlear implants (Device)
Healthy volunteers
4 states and each state will be repeated 3 times Auditory stimulation Left ear only Auditory stimulation right ear only Binaural auditory stimulation Silence
结局指标
主要结局
Increase our understanding of why outcomes following a cochlear implant are heterogenous. This information may be used to provide targeted rehabilitation for candidates performing poorly with their implants and minimise rejection of the implant.
时间窗: 1 year
We anticipate that the recruitment of patients, data collection and analysis would take a maximum of 4 months Study Group PET scans for the mature patients with unilateral cochlear implants and preserved hearing 4 states and each state will be repeated 3 times Cochlear implant only Residual hearing only Combination of implant and residual hearing No auditory stimulation Control Group 4 states and each state will be repeated 3 times Auditory stimulation Left ear only Auditory stimulation right ear only Binaural auditory stimulation Silence
次要结局
- Combine the data from both of our studies and future studies in order to conduct meta-analysis to investigate further how language is processed in patients with cochlear implants.(1 year)
- Determine if functional neuroimaging modalities have a future role in the selection process for potential cochlear implant candidates and in predicting outcome for each individual.(1 year)