Spontaneous Spontaneous<unk> s (SOAE)s are sounds that are emitted from the ear without external stimulation and are measurable with sensitive microphones in the external ear canal. At least one SOAE can be detected in approximately 35–50% of the population. The sounds are frequency-stable between 500 Hz and 4,500 Hz and have unstable volumes between -30 dB SPL and +10 dB SPL. The majority of the those with SOAEs are unaware of them, however 1–9% perceive a SOAE as an annoying tinnitus. Evoked Evoked<unk> s are currently evoked using three different methodologies. * Stimulus-frequency<unk> s (SFOAEs) are measured during the application of a pure-tone stimulus and are detected by the vectorial difference between the stimulus waveform and the recorded waveform (which consists of the sum of the stimulus and the<unk> . * Transient-evoked<unk> s (TEOAEs or TrOAEs) are evoked using a click (broad frequency range) or toneburst (brief duration pure tone) stimulus. The evoked response from a click covers the frequency range up to around 4 kHz, while a toneburst will elicit a response from the region that has the same frequency as the pure tone. * Distortion-product<unk> s (DPOAEs) are evoked using a pair of primary tones and with particular intensity (usually either 65–55 dB SPL or 65 for both) and ratio (). The evoked responses from these stimuli occur at frequencies () mathematically related to the primary frequencies, with the two most prominent being (the "cubic" distortion tone, most commonly used for hearing screening), because they produce the most robust<unk> , and (the "quadratic" distortion tone, or simple difference tone).
Otoacoustic emission
Vibroacoustic stimulation
Photoacoustic imaging
Conditioned play audiometry
Auditory brainstem response
Vibroacoustic therapy
Pure-tone audiometry
Visual reinforcement audiometry