Simulation of hearing impairment with sensorineural hearing loss

A hearing impairment simulation (HIS) tool is developed. The tool is aimed to simulate sensorineural hearing impairment. In the HIS algorithm, the impairment model is established from auditory test data of the impaired subject being simulated. Also, the nonlinear behavior of the loudness recruitment is defined using hearing loss functions generated from the measurements. To transform the input natural sound into the impaired one, a frequency sampling filter is designed. The filter is continuously refreshed with the level-dependent frequency response function provided by the impairment model. To assess the performance, the HIS algorithm was implemented in real-time using a floating-point DSP. Signals processed with the real-time system were presented to normal subjects and their auditory data modified by the system was measured. A sensorineural hearing impairment was simulated and tested. Hearing threshold and speech discrimination tests exhibited the efficiency of the system in its use for the hearing impairment simulation.