Testing and evaluation paradigms for assistive hearing devices

Research interfaces and assistive hearing devices (RI/AHD) enable investigators to perform perceptual studies and develop effective sound processing strategies for cochlear implant (CI) and hearing aid (HA) devices. Several concerns exist regarding safe and reliable operation of RI/AHDs, for example, safety, reliability, possible hazards, accuracy, and their long-term consistency. Recently, CRSS-CILab at UTDallas has developed a mobile RI (CCi-MOBILE) for unilateral and bilateral HA/CI devices. In this study, a comprehensive testing and evaluation strategy is proposed to investigate the behavior of RI/AHDs that addresses safety concerns, reliability of hardware/firmware design, hearing-comfort, subjective sound-quality, and range of human-driven settings, as well as diverse types of acoustic exposure. Furthermore, a characteristic risk-hazard analysis is performed including diagnosis and categorization of the severity level of the associated safety concerns by probing pulse characteristics from each electrode, e.g., current-level, pulse-width, charge per phase, frame-period (for stimulation-rate), inter-phase gap (IPG), and several other parameters. The CCi-MOBILE RI is employed in this study to demonstrate the utility of the proposed testing and evaluation paradigm. The described practices could potentially serve as a blue-print to characterize future RI for AHDs and several other personalized listening devices based on safety, reliability, listening comfort/perception, and subjective sound quality.