Final answer:
Conductive hearing loss, which occurs in the middle ear, can be improved with ordinary hearing aids by amplifying sound vibrations that are sent to the cochlea. However, if the auditory nerve is abnormal, neither hearing aids nor cochlear implants would improve hearing. A 50-dB hearing loss requires sounds to be amplified by 100,000 times for them to seem normal.
Step-by-step explanation:
The type of hearing loss that can be improved with ordinary hearing aids is conductive hearing loss, which occurs in the middle ear. These hearing aids work by sending sound vibrations to the cochlea through the skull. On the other hand, damage to the nerves in the cochlea cannot be fully repaired, but amplification provided by hearing aids can offer partial improvement. However, there's a risk that amplification could potentially cause further damage. For cases where there is damage or loss of the cilia in the cochlea but the nerves are still functional, cochlear implants are an effective treatment as they stimulate the nerves directly.
Hearing loss that would not be restored by a cochlear implant includes cases with an abnormal auditory nerve, because the cochlear implant requires a functional auditory nerve to transmit sound to the brain. For example, hearing loss resulting from an abnormal auditory nerve would not be improved by a cochlear implant.
If a person has a 50-dB hearing loss at all frequencies, low-intensity sounds would need to be amplified by a factor of 10 for every 10 dB of hearing loss, meaning low-intensity sounds would need to be amplified by a factor of 100,000 times to appear normal.