Amplification of the Auditory Signal on the Way to the Center

Abstract

A person receives auditory information from the environment in terms of sound intensity between 0 dB = 10⁻¹² W/m² and 120 dB = 1 W/m². The difference in intensity levels is a trillion times. Converted into the amplitude of the sound wave, it ranges from 8 pm to 10,000 nm. The pain threshold of 130 dB is 10 W/m². Hearing loss 140 dB = 100 W/m². Destruction of the ear, rupture of the eardrum 160 dB = 10,000 W/m². The difference between hearing threshold and eardrum destruction is 15 orders of magnitude — a quadrillion. Waves that are above the auditory threshold are received without amplification of the signal before the receptor. According to the traveling wave theory since the 1980s, it is believed that quiet tones are amplified in front of the receptor by 40 dB, thanks to the contractions of the OHC, which are supposed to be an amplifier for the IHC. According to other views, sounds are amplified in the hair cell and further to the center, the energy of which is too low to reach the CNS. This takes place at the level of molecular changes.