High-frequency sounds primarily cause vibration in which part of the ear?

High-frequency sounds primarily impact the hair cells nearest the oval window because of how the cochlea is structured. The cochlea is a spiral-shaped organ in the inner ear that contains the basilar membrane, where hair cells are located. Higher frequency sounds create waves that peak closer to the base of the cochlea, which is near the oval window. This structure is designed in a tonotopic fashion, meaning different frequencies trigger responses at specific locations along the basilar membrane.

When high-frequency sound waves enter the ear, they cause the fluid inside the cochlea to move, leading to vibrations that stimulate the hair cells closest to the oval window. This stimulation translates into electrical signals sent to the brain, allowing us to perceive high-pitched sounds. The anatomical position of the hair cells and the physical properties of sound waves explain why the cells closest to the oval window are responsible for detecting these higher frequencies.