AMP Benchtop Dataset

Abstract—
Background: Cochlear implants (CI) are a well-established treatment option for patients with severe to profound hearing loss, while vestibular implant (VI) trials give a promising outlook for patients with severely impaired vestibular function. In a number of subjects these two conditions may also present together, which could require treatment with a CI and a VI at the same time, or with a combined cochleo-vestibular implant (CVI). Several studies have demonstrated the feasibility of a combined CVI, yet until now no wearable processor solution has been available to provide target-specific modulated input which concurrently stimulates both targets for an extended period of time.

Objectives: We present a first wearable audio-motion processor system designed to be used in conjunction with a CVI. In this study we investigate the performance characteristics of this device on a test bench. Important performance characteristics of such a system are the latency between head movements and resulting vestibular stimulation pulses, and the deviations of stimulation amplitudes and pulse rates from a programmed transfer function (TF).

Methods: Amplitude- and rate-modulated vestibular pulses were evaluated in response to predefined movements performed on a rotary platform, while audio stimulation was simultaneously provided to cochlear electrodes. Predefined single axis rotations were applied to the system, different fitting parameters were configured, and the resulting stimulation pulses at the electrodes were recorded.

Results: The latencies of movement-modulated stimulation pulses were dependent on the configured fitting parameters. We were able to achieve a recorded latency of 6.5 ms or less for typical fitting parameters, which is comparable to the physiological response time of the vestibular organs. The results for the TF showed that the measured values for the pulse rates and the amplitudes followed the reference values very accurately, with deviations of less than 3.56%.

Conclusion: With appropriate fitting parameters, the presented audio-motion processor system can deliver stimulation to the vestibular system with a latency comparable to that of a healthy vestibular organ, while concurrently providing auditory stimulation to the cochlea. It is the world’s first wearable processor capable of delivering combined, specifically modulated cochlear and vestibular stimulation.