Which reflex involves the contraction of stapedius muscle?

The contraction of the stapedius muscle is primarily involved in the acoustic reflex, which is also known as the stapedius reflex. This reflex is a protective mechanism of the auditory system that helps to reduce the transmission of loud sounds to the inner ear. When a loud sound is detected, the stapedius muscle contracts, which in turn reduces the movement of the stapes bone (one of the three ossicles in the middle ear). By dampening the sound vibrations that reach the cochlea, the acoustic reflex helps in protecting the hearing structures from potential damage caused by excessive noise exposure. This reflex is automatic and typically occurs in both ears, even if the loud sound is only presented to one ear. The importance of the acoustic reflex lies in its role in enhancing auditory perception and safeguarding hearing integrity.

In contrast, the vocal reflex relates to the production of sounds or speech, the optical reflex concerns visual stimuli and responses, and the somatic reflex pertains to motor responses of skeletal muscles. These other reflexes do not involve the stapedius muscle or the auditory system directly.