We hear our own sounds, particularly our voice, through a combination of air conduction and bone conduction.
Understanding the Two Pathways
Our hearing relies on two primary mechanisms: air conduction and bone conduction.
Air Conduction
- This is how we typically hear sounds from the external environment.
- Sound waves enter the ear canal and vibrate the eardrum.
- The eardrum vibrations are then transmitted through three tiny bones in the middle ear (malleus, incus, and stapes) to the cochlea in the inner ear.
- The cochlea converts these vibrations into electrical signals, which are sent to the brain via the auditory nerve, allowing us to perceive sound.
Bone Conduction
- Bone conduction allows us to hear sounds through vibrations transmitted directly through the bones of our skull to the inner ear (cochlea), bypassing the outer and middle ear.
- When we speak, the vibrations from our vocal cords travel not only through the air but also through the bones of our head, specifically the temporal bone.
- These vibrations stimulate the cochlea directly, resulting in auditory perception.
- This explains why we can still hear our own voice even when we block our ears.
Why Our Voice Sounds Different to Us
The reason our voice sounds different to us when recorded is because we usually hear it through a combination of both air and bone conduction. A recording captures only the air-conducted sound, which lacks the lower frequencies that are amplified through bone conduction.
Key Differences in Perception
| Feature | Air Conduction | Bone Conduction |
|---|---|---|
| Source | External sounds | Internal vibrations (e.g., speaking) |
| Pathway | Outer ear -> Middle ear -> Inner ear | Skull bones -> Inner ear |
| Frequency Range | Typically higher frequencies are more dominant | Typically lower frequencies are more noticeably heard |
In conclusion, we hear our own sound through both air and bone conduction. Bone conduction is a particularly important mechanism for hearing our own voice. The unique combination of these two pathways shapes our perception of self-generated sounds, which is why our voice sounds different on a recording.
