Cochlear Implants

Severe to profound hearing loss affects 0,8% of the global population. For these people, a conventional hearing aid often does not provide sufficient benefit. However, these people can benefit from a cochlear implant (CI). A CI needs to be individually programmed (fitted) for each recipient. A fitting "map" is defined as a set of electrical parameters that are individually adapted to a recipient's needs to achieve optimal sound perception. At present, most CI recipients are fitted with a default frequency allocation map that doesn't take individual variability in size and shape of the cochlea into account. In this study, a fitting strategy based on the post-operative CT scan, that will allow the audiologist to set a frequency-band distribution for CI fitting that may be more closely aligned to the natural tonotopic frequency distribution of a normal hearing cochlea, will be evaluated.

The goal of this clinical trial is to learn if cochlear implant activation affects spatial orientation in cochlear implant users. The main question\[s\] it aims to answer are\]: * Does activation of the cochlear implant improve spatial orientation? * Is this improvement caused by better hearing ability through the cochlear implant? Participants will: * Take an online survey including questions about their cochlear implants and clinical questionnaires on dizziness and spatial orientation * Undergo balance and spatial orientation tests under different cochlear implant conditions.

One of the most significant challenges in cochlear implant programming, particularly for very young children and those with an associated pathologies, is the measurement of subjective comfort levels (= C-Subjective). Currently, to define this C-Subjective level, patients are presented with a loudness scale and must indicate whether the sound stimulus, sent via the implant, is soft, comfortable, or loud. The lower and upper stimulation levels must be determined for each electrode in order to program the implant. For many patients this can be difficult due to a lack of auditory experience and confusion between the sensation of sound intensity (weak or loud) and frequency (low or high). A less commonly used but more objective approach to programming upper stimulation levels involves the use of the electrical stapedial reflex threshold (eSRTs) value. eSRTs are a promising measure, given the demonstrated correlation between the threshold that generates a stapedial reflex and the C-subjective level. Furthermore, eSRTs can be recorded in the majority of patients, and can typically be evoked at a comfortable stimulation level i.e. inferior to the uncomfortable level. The main objective of this study is investigate the link between subjective comfort levels (C-subjective levels) and the eSRT.

In the field of cochlear implant research, there are only few data on long-term observational studies available to gain knowledge on clinical effectiveness. Longitudinal comparisons of data collected in different clinics is challenging due to the heterogeneity in measures and procedure. This Registry represents a non-interventional systematic collection of clinical data in which prospective data from children and adults are collected as anonymized data sets, derived from original clinical records on appropriately informed subjects. Each subject will be treated as per clinical routine. The Registry will be implemented through a secure, cloud-based, platform that enables collection of anonymized data at consistent time intervals, thus enabling the comparison of repeated measures over time.

The purpose of this study is to compare the effectiveness of a free computer-based auditory training program, Sound Success (Advanced Bionics, Valencia, CA), with the current standard of care of patient-directed auditory training in improving common measures of speech recognition and cochlear implant (CI) specific quality-of-life in new adult CI recipients in their first year post-activation.

The goal of this study is to improve music and speech perception for cochlear implant users. Presently, most cochlear implants discard the temporal fine structure of sound, which is information that is widely believed to contribute to both music and speech perception. The proposed work examines perceptual and physiological changes that occur once this information is provided to cochlear implant users in a clear and consistent manner.

The current standard of care approach for programming cochlear implants uses a generalized pitch-map for all patients. This approach fails to account for individualized inner ear anatomy. As a result, many cochlear implant recipients experience place-pitch mismatch. We have recently developed an automated mathematical tool to produce patient-specific, customized cochlear implant pitch-maps (Helpard et al., 2021). In this study, cochlear implant recipients will be randomized to receive either the clinical default pitch-map (the control group) or a place-based pitch-map (the intervention group). Assessments will be conducted at multiple time-intervals to account for patient acclimation and plasticity to both the generalized and individualized pitch-maps. Audiological assessments will be tuned to identify patients' ability to discern pitch scaling and variation in sounds, as well as to understand complexities in speech such as mood and tone. Audiological testing will be conducted in collaboration with the National Centre for Audiology (London, ON) to ensure that the most accurate and relevant metrics are applied.

Pitch perception and memory are central in auditory cognition, in particular for sound source segregation and recognition, speech prosody and music processing. Here the investigator assess pitch perception and memory in hearing-impaired listeners wearing cochlear implant(s) and listeners with congenital amusia, both compared with control listeners. Behavioral, EEG, and MEG measures are collected in audio and audio-visual contexts to characterize pitch processing deficits, and test a pitch training program.

This is a prospective multicenter multinational randomized control trial. The duration of the study for the individual patient will be approximately 1 year (pre-operative assessments, 1 week, 3 months and 12 months follow-up assessments). Participants will be randomized to one of two surgical approaches: eRW or CO, with a 1:1 allocation in a parallel design.

The goal of this interventional clinical study is to investigate the use of mild therapeutic hypothermia for preservation of residual hearing in cochlear implant surgery. The main questions the trial aims to answer are: 1. Is mild therapeutic hypothermia safe for use during cochlear implantation? 2. Is mild therapeutic hypothermia effective at preserving residual hearing after cochlear implantation? Participants will receive mild therapeutic hypothermia therapy during cochlear implant surgery. Researchers will compare results from those receiving the therapy to those from a control group (individuals receiving no therapy).