Q

AP PSYCH 3.5 Auditory Sensation and Perception

Sound Waves

  • Sound waves have various qualities that we interpret differently
  • High frequency sounds have more waves in a shorter distance
  • High amplitude sounds have higher distance between the peak and trough of the wave
    • The opposite is true for low frequency/amplitude sounds

The Ear

  • The earā€™s function is to intake sound waves and to transduct those waves into neural impulses our brain can understand

Outer Ear

  • This includes the pinna, external auditory canal, and tympanic membrane
  • The pinna is the flesh and cartilage around the ear canal
    • Itā€™s odd shape helps funnel as much sound as possible into the ear
  • The external auditory canal is the tunnel that sound travels though
  • The tympanic membrane, or ear drum, divides the outer from the middle ear
    • The tympanic membrane vibrates when sound reaches it, transferring it to the ossicles
  • The overall function of the outer ear is to gather, concentrate, and amplify sound waves

Middle Ear

  • Sound waves are now traveling through solids, not the air
  • The hammer, anvil, and stirrup are three very small bones, also known as ossicles
  • They receive vibrations from the eardrum

Inner Ear

  • Sound waves are traveling through the liquid in the cochlea
  • The cochlea is a spiraled tube with little hairs, cilia, inside
  • The cilia receive the vibrations are are linked to the auditory nerve
  • Cilia are the site of transduction

Hearing Phenomenon

Hearing Loss

  • There are two different kinds of hearing loss

Sensorineural Hearing Loss

  • Hearing loss due to impairment of the cilia and/or auditory nerve
  • This will effect both ears
  • It impacts volume, clarity, and range of sounds heard
  • The more common type of hearing loss
  • Often because of aging, can also be from trauma (either a single event or chronic) and diseases

Conductive Hearing Loss

  • This is caused by an impairment in the outer ear, ear drum, and/or ossicles
  • This may affect only one ear
  • Sound waves are not progressing normally through the ear and causes distortion
  • May be because of blockage, physical trauma