Hearing and Speech Hearing Loss
Hearing and Speech Hearing Loss

There are four types of hearing loss: conductivesensorineuralmixed and auditory neuropathy. All can be either congenital or acquired. Congenital means the child is born with hearing loss. Acquired means the hearing loss happens after birth.

There are also five degrees of hearing loss: mildmoderatemoderately severe, severe and profound.

Children will have either unilateral hearing loss or bilateral hearing loss. Unilateral means only one ear has hearing loss. Bilateral means both ears have hearing loss.

Types of Hearing Loss:

Conductive Hearing Loss

conductive hearing lossWhen sound does not move clearly through the outer and middle ear to the inner ear, it is called conductive hearing loss. In most cases, the problem can be fixed with medical help, but sometimes it can be permanent.

Usually, an ear infection causes temporary conductive hearing loss. When an infection or fluid blocks the middle ear, the eardrum and the bones cannot vibrate like they should. This stops sound from getting to the inner ear and causes the child to have problems hearing.

Sometimes a middle ear infection is not the cause of conductive hearing loss. Too much ear wax, damaged middle ear bones, and abnormal middle or outer ears can also cause this type of hearing loss. In these cases, the child can wear hearing aids to hear better.

Sensorineural Hearing Loss

Problems with the inner ear or the auditory nerve are called sensorineural hearing loss. Damage to the inner ear comes in different degrees: the more damage, the more hearing loss.

Some pitches may be affected more than others. This type of hearing loss usually leads to problems with hearing soft sounds and problems with understanding speech. 

sensorineural hearing lossCauses of sensorineural hearing loss:

  • Heredity
  • Trauma at birth
  • Certain syndromes
  • Certain drugs (prescription as well as illegal)
  • Head injury
  • Exposure to loud noise
  • Tumors
  • Aging process

Sensorineural hearing loss is permanent. Usually, it cannot be treated medically. However, it can be treated with amplification and hearing aids.

Depending on the level of hearing loss and the pitches that are affected, the audiologist may suggest that the child try hearing aids. However, hearing aids are not like glasses; they will not give a child normal hearing. Hearing aids may help make some sounds heard that were not heard before but making sound loud enough does not always make sound easier to understand. With hearing aids, speech may still sound distorted to the child, because hearing loss affects the inner ear in different ways. 

Mixed Hearing Loss

Some children have hearing loss in both the middle (conductive) and the inner ear (sensorineural). This is called mixed hearing loss.

Auditory Neuropathy Spectrum Disorder (ANSD)

ASNDAuditory neuropathy spectrum disorder (ANSD) is also called auditory neuropathy or auditory dys-synchrony.

If a child has this type of hearing loss, sound is entering the  cochlea like normal, but the nerve that is supposed to send signals to the brain (the  auditory nerve) is not working right.

This causes children to have a wide variety of problems with hearing. Some may have mild problems; others severe. Some children may have problems hearing and understanding sounds, need visual cues to understand a conversation, or have delays with speech and language. This is why auditory neuropathy is called a spectrum disorder: no two children with ANSD are exactly alike and not all will have the same difficulties.



Degrees of Hearing Loss:

Mild Hearing Loss

With mild hearing loss, children cannot hear sounds softer than 25-40  decibels (dB). An example of sound they cannot hear is whispering, which is around 40 dB. They also cannot hear some soft speech sounds even when spoken at a normal level. Some sounds they may have a problem hearing are /s/, /f/, and /th/.

If a child does not get a hearing aid or implant to increase sound or is not helped early in life, the hearing loss can cause inattention, language delays and speech problems. Sounds that are somewhat loud to a normal hearing person, such as speech, will sound like a whisper to the child.

With help, such as hearing aids and therapy, most children can understand the soft sounds of speech and the world around them.

Moderate Hearing Loss

Sounds softer than 40-55  dB cannot be heard by children with moderate hearing loss.

Without help, most speech sounds will not be heard. Sounds that are loud to a normal hearing person will be a whisper to the children. They will only understand speech if it is loud. Children may have errors in their speech. They may not pay attention and may have speech, language and learning problems. An adult may have a hard time understanding the child. 

With help, most children can understand soft sounds of speech. Most children will develop vocabulary, language understanding and talking. Most children will learn to speak clearly if they wear hearing aids everyday, all day.

Moderately Severe Hearing Loss

Children with this degree of hearing loss have problems hearing sounds softer than 55-70  dB. An example of a sound at this level is a dishwasher (60 dB).

Without help, children with this amount of hearing loss can hear and understand a loud voice very close to them. They usually do not develop speech and language on their own, and if they do, their speech will be poor.

Hearing aids will help these children hear conversation. If the children get speech and language therapy, they can understand and make most speech sounds.

Severe Hearing Loss

With severe hearing loss, children cannot hear sounds softer than 70-90  dB. Examples of a sounds they may not hear are a vacuum (70 dB), or a blender and a hairdryer (90 dB).

Without help, the child will have problems understanding most speech sounds. Other loud sounds may not be heard at all. The child will hear no speech sounds at normal conversation level. Sounds that are very loud to a normal hearing person will be very soft to the child. Speech will only be heard if it is shouted in the child's ear. A child with this degree of hearing loss will have speech that is not understandable.

With the help of hearing aids or implants and therapy, children with this degree of hearing loss often can understand most sounds. They can learn to understand and speak, even though they will not hear speech the way children with normal hearing do. Most children will need help in school to make up for problems they have with hearing in noisy places or hearing far away sounds.

Profound Hearing Loss

Children with profound hearing loss cannot hear sounds softer than 91 dB. Examples of this are MP3 players with the volume turned up all the way (100 dB) and car horns (110 dB).

These children must have special education to help them learn language and speech. Without this help, children cannot hear sounds. They use sight instead of hearing to communicate. People with normal hearing cannot understand their speech.

However, technology and therapy can help children with profound hearing loss. With a hearing aid or cochlear implant, many children will hear loud sounds and spoken conversation if there is no background noise and they are facing the speaker. Many children still need to use visual cues (read lips, see facial expressions, etc.) to help them understand spoken conversation. Most children with a profound hearing loss also need help at home and school to improve their speech and language.

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