EAR JOURNEY

OUTER EAR

• The sound waves hit the outer ear
• The visible part of the outer ear is also called the pinnae

AUDITORY CANAL

• The waves are channeled through the auditory canal
• The auditory canal serves as a passageway for sound waves

EARDRUM

• It then arrives at the eardrum, which vibrates
• The eardrum is a tight membrane found between the outer ear and the middle ear

MIDDLE EAR

• The middle ear then transmits the eardrum's vibrations through the piston
• The piston is made of the hammer, the anvil, and the stirrup

INNER EAR

• It arrives at the cochlea in the inner ear
• The cochlea vibrates
• The cochlea is a spiral shaped tube in the inner ear

COCHLEA

• The cochlea's vibrations jostle the fluid that fills the tube of the cochlea

BASILAR MEMBRANE

• The motion causes ripples in the basilar membrane
• This bends the hair its surface

TRANSDUCTION

• Hair cell movement triggers impulses in the adjacent nerve cells
• Their axons converge to form the auditory nerve
• This is the part of the process where energy is transduced

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• The auditory nerve sends neural messages via the thalamus
• They arrive at the temporal lobe's auditory cortex

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• The amplitude of a sound wave is its height
• It changes the loudness of a sound

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• The wavelength is the length of a soundwave
• It determines the frequency of a sound

PLACE THEORY

• Developed by Hermann von Helmholtz
• Different sound waves trigger activity at different spots on basilar membrane
• Brain determines the pitch based on the place where the signal is generated
• Explains high pitched sounds, but not low pitched sounds

FREQUENCY THEORY

• Brain monitors the frequency of neural impulses in auditory nerve
• The higher the frequency of the sound wave, the more neural impulses
• The brain uses this to determine pitch