The Sense of Hearing: Audioception

Senses are the brain’s capability to process information from the surrounding environment, commonly referred to as “perceiving.” It’s important to know that each sense is a system of sensory cells that corresponds to a particular region of the brain where signals are received and then interpreted. In humans, there are a variety of senses. Today, we are focusing on the sense of hearing, otherwise known as “Audioception,” and how it’s affected by Sensory Processing Disorder.

In the broadest sense, hearing is about vibration. Sound itself is vibrations that travel through the air, our bodies ability to detect these vibrations is known as the sense of hearing. There are mechanoreceptors are located in the inner ear, pick up these vibrations and pass them through tiny bones called the ossicles and into the cochlea where it is then turned into electrical nerve pulse signals for the brain to interpret.

When someone has Sensory Processing Disorder, their ability to handle sound vibration can either be hypersensitive or hypo-sensitive. Hypersensitivity is caused by a malfunction of the stapedius. The stapedius muscle contracts in responses to loud noises to protect our ear drum. When this fails to happen, noises appear much louder and the ability to filter our background noise is difficult. On the other side of the coin, hypo-sensitivity where the child cannot distinguish sounds or looks for louder sounds.

Here are some indicators that your child might be hypersensitive or hypo-sensitive to noise:

  • afraid of the vacuum, hair dryers, or toilet flushing
  • overreaction to loud sounds (covering ears, crying, running away or aggression)
  • annoyed or distracted by common sounds (fans, clocks, refrigerators)
  • keeps music, radio or television very loud
  • dislikes crowds
  • makes noise to just make noise
  • makes other people repeat themselves often because of not understanding
  • unable to determine the location of a sound

In some cases, your child might have what is referred to as Auditory Processing Disorder, where they have the ability to hear but struggle to process what they are hearing.

Well known example of this is demonstrated below:

Teacher: “Tell me how a chair and a couch are similar”
Student with APD: “Tell me how a cow and hair are similar”

The primary difference between this and hyper/hypo sensitivity is the problem lies with the understanding of the sounds rather than the volume of the sounds. The number of children with Auditory Process Disorder is estimated between 2-7%.

There are four types of auditory processing disorders:

  1. Auditory Discrimination – the inability to notice or compare between distinct and separate sounds (seventeen and seventy might be hard to distinguish)
  2. Auditory Figure-Ground Discrimination – inability to focus on important sounds in a noisy setting
  3. Auditory Memory – inability to recall what you’ve heard or what was said
  4. Auditory Sequencing – inability to understand and recall the order of sounds or words (for example, hear the number 357 but write down 735).

Here are some indicators that your child might have Auditory Processing Disorder:

  • has trouble following spoken directions
  • easily distracted by noises and background noises
  • has trouble with phonics involved with reading and spelling
  • struggle with oral math problems
  • can’t follow long conversations
  • can’t learn songs or nursery rhymes

When your child is suffering from either hyper/hypo sensitivity or Auditory Processing Disorder it can have a direct impact on their communication, their academic life, and their social skills. If you feel that your child might need help contact a speech and language pathologist or your school psychologist.