Authors: Eva Koderman1, Mark van Kesteren1, Timothé Guyonnet-Hencke1, Jennifer Goodall1
Background: The pure-tone audiometry (PTA) relies on patients’ behavioral responses, which can be problematic for individuals unable to understand instructions, such as those with neurological disorders or infants. This results in a large portion of the population being misdiagnosed. MindAffect’s Hearing Diagnostic System (MAHDT) is an objective, affordable, and comfortable EEG-based device for audiometric testing. The first validation study of the prototype was performed in collaboration with the Hörzentrum Institute in Oldenburg in September 2022.
Methods: 25 subjects, including 20 hearing impaired (HI) and 5 normal hearing (NH), were tested for 12.5 minutes with a 32-electrode system in a double-blinded study. Both ears were tested using 4 different tone frequencies (500, 1000, 2000, and 4000 Hz) at 18 different intensities (starting at no sound and increasing in 5 dB steps from -10 dB to 70 dB).
Results: The absolute difference between PTA and MAHDT thresholds averaged across all frequencies was 5.5 dB and the rate of outliers (% of error > 10dB) was 9.5 %. The mean error for the frequencies 500-2000 Hz was 5 dB with an average outlier rate of 8%. The mean error (7dB) and the average outlier rate (14%) were higher for the 4000 Hz. A time analysis of the 32-channel dataset demonstrated the potential to reduce the testing time to 6 and a half minutes for all frequencies.
Conclusions: The results of the double-blind study show the effectiveness of the 32-channel MAHDT system for diagnosing hearing impairment in individuals, demonstrating the potential for further improvement and development of the system. Patients that are difficult to measure with the standard PTA, such as infants or patients with mental disabilities, would benefit from our system the most.