The most used method in manual audiometry is the modified Hughson-Westlake procedure, also described in ANSI S3.21-1978 (R-1992). The shape of the psychometric function depends on the particular audiometric test procedure, used by the audiologist. The psychometric function describes the probability of a positive response as a function of the pure-tone level. Since nerve cell activity is essential random, the threshold can only be interpreted as stimulus level where the pure tone is detected with some predefined probability. The lowest sound level at which the pure tone at a standardized frequency is heard, is called “hearing threshold,” expressed in hearing level of decibel relative to the quietest sound a standardized young healthy individual ought to be able to hear. To eliminate its participation from the test, the contralateral cochlea is stimulated by narrow-band masking noise centered around the pure-tone frequency. An overview of mean value and range of this so-called interaural attenuation for AC and BC hearing tests can be found in and, respectively. An acoustic stimulus presented to the ipsilateral ear does not necessarily stimulate the ipsilateral cochlea only, but also crosses the skull, gets attenuated, and stimulates the contralateral cochlea. To test bone-conduction (BC) hearing, pure-tone vibrating force is placed on the ipsilateral mastoid, bypassing the middle ear. The procedure is repeated for specific frequencies typically in the range from 2 Hz. Sound propagates into the ear through air in the auditory ear canal. To test air-conduction (AC) hearing, pure-tone sound pressure is applied to the ipsilateral ear through an earphone. This test is performed with an audiometer, comprising a single tone generator, a bone vibrator for measuring the cochlea function, and earphones for air-conduction testing. Pure-tone audiometry is a behavioral test used to identify hearing threshold levels of an individual. To evaluate the practitioner’s testing skills, there is currently no standard available. In combination with counseling of hearing impaired persons and their family, this will make it possible to achieve successfully hearing (re)habilitation. If diagnosed accurately, hearing loss can then be managed by technology or corrected by surgery. To identify auditory impairment, the audiologist makes an audiometry exam. Disabling hearing loss refers to hearing loss greater than 40 dB in the better hearing ear in adults and a hearing loss greater than 30 dB in the better hearing ear in children. So far, 328 million adults and 32 million children suffer from disabling hearing loss. The proposed approach sets a new quality standard for evaluating practitioners. The frequency range is confined within 2 Hz. The AP handles masked air-conduction and bone-conduction hearing levels in the range from 5 to 80 dB and from – 20 to 70 dB, respectively, both at 1 kHz. The AP is derived within a theoretical framework in contrast to many other solutions. The AP returns a feedback signal to the practitioner upon perceiving a valid test tone at the hearing threshold analogous to a real patient. The model is then used to realize a hardware implementation, comprising acoustic and vibration sensors, sound cards, and a fanless personal computer. Following this approach, we develop a multiple-input multiple-output auditory model that synthesizes various types of hearing loss as well as elements from psychoacoustics such as false response and reaction time. To assess every practitioner equally, the paper proposes a first machine, dubbed artificial patient (AP), mimicking a real patient with hearing impairment operating in real time and real environment. So far, there is no standard available to evaluate the practitioner’s testing skills. The successful treatment of hearing loss depends on the individual practitioner’s experience and skill.
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