[7] The stapedius stiffens the ossicular chain by pulling the stapes (stirrup) of the middle ear away from the oval window of the cochlea and the tensor tympani muscle stiffens the ossicular chain by loading the tympanic membrane when it pulls the malleus (hammer) in toward the middle ear.

The reflex decreases the transmission of vibrational energy to the cochlea, where it is converted into electrical impulses to be processed by the brain.

People with conductive hearing loss (i.e., bad transmission in the middle ear) may have a greater or absent acoustic reflex threshold.

[10] The main hypothesized function of the acoustic reflex is the protection of the organ of Corti against excessive stimulation (especially that of the lower frequencies).

[13] According to the article Significance of the stapedius reflex for the understanding of speech, the latency of contraction is only about 10ms, but maximum tension may not be reached for 100 ms or more.

[17][13] However, when several sudden intense noises are presented at a pace higher than 2–3 seconds of interval, the acoustic reflex is able to play a role against auditory fatigue.

[19] An alternative hypothesis for the role of the acoustic reflex is the prevention of auditory masking of high-frequencies by low-frequencies, which are predominant in natural sounds.

The pathway involved in the acoustic reflex is complex and can involve the ossicular chain (malleus, incus and stapes), the cochlea (organ of hearing), the auditory nerve, brain stem, facial nerve, superior olivary complex, and cochlear nucleus.