boneconducted

Bone conduction is a method of sound transmission in which vibrations are delivered to the bones of the skull, bypassing the outer and middle ear so the inner ear is stimulated directly. The resulting neural signals are interpreted by the brain as sound.

Vibrations produced by bone-conduction devices set the skull into motion, transmitting energy to the cochlea through the cranial bones. This can be accomplished with external devices that press against the mastoid or temple, or with surgically implanted systems that anchor a vibration transducer to the skull.

The most common clinical implementations are bone-conduction headphones and bone-anchored hearing aids (BAHA). BAHA devices attach to an osseointegrated implant in the skull and transmit vibration from an external processor. With percutaneous implants, an abutment passes through the skin; with transcutaneous systems, magnets transmit the energy without a skin breach.

Bone conduction is especially useful for conductive or mixed hearing loss, where sound cannot reach the inner ear through the middle ear, and for people with conditions such as chronic otitis externa, atresia, or external ear canal obstruction. It is also used in specialized settings, for example by swimmers or workers who require ear protection.

Limitations include variability due to skull thickness and anatomy, reduced high-frequency response for some users, and skin irritation or infection risk with percutaneous implants.

Historically, the concept of bone conduction informed later development of osseointegrated and other bone-conduction devices. Related topics include osseointegration and cochlear implants.