Ear Center: iSense Dynamic FM Device

iSense - A Dynamic FM Device by Phonak to Help "Link" the Student with His/Her Teacher

Auditory Processing Disorder - The Problem

When children are diagnosed as having special learning or behavioral disorders

  1. inability to focus
  2. short attention spans
  3. lack of understanding
  4. inability to complete tasks such as sequential commands or instructions
  5. trouble remembering and repeating instructions
  6. unusual sensitivity to sounds
  7. difficulty understanding in noisy environments
  8. confusing similar sounding words
  9. poor impulse control
  10. socially unacceptable behaviors

Parents often seek professional advice as to what can be done to help their child become more successful, especially in the classroom.

Most of these children manifest "Performance Deficits" and are otherwise:

  1. healthy children without other physical or mental health conditions
  2. have normal intelligence
  3. have normal auditory reception ability (have normal ears that receive sound normally)

In addition, exceptional children with special needs frequently manifest performance deficits.

It is estimated that 3-5% of children with performance deficits have varying degrees of central "Auditory Processing Disorder" (APD). Auditory Processing Disorders (APD) are due to dysfunction within the brain's central auditory pathways. Children with APD are physically able to hear sounds (auditory reception) but have difficulty processing sound (auditory perception), comprehending speech, and grasping the meaning of what is said (disorders of binaural fusion, background noise, and auditory memory/auditory sequential memory). APD may be responsible for some speech disorders in children and may contribute to common reading (Dyslexia) and writing disorders (Dysorthographia). Other children are diagnosed as having "Attention Deficit/Hyperactivity Disorder" (ADD or ADHD) or have identifiable Learning Disabilities. It is estimated that 4-12% of children are affected by Attention Deficit Disorder, and 5-7 % of children have Learning Disorders.

What Options Are Available?

Aside from various medications which must be individualized and carefully monitored, many children with Performance Deficits benefit from being able to clearly hear their teacher's voice without interference from competing background noise. Teacher's voices produce approximately 65 dB. of loudness during normal conversation in the classroom. Environmental noise in a classroom comprised of young children may easily reach 60-64 dB. In essence, the teacher's voice is only slightly louder than the ambient background noise. Combined with poor classroom acoustics (many flat, reflecting surfaces creating echoes, etc.), the teacher's voice is not easily heard by children with Performance Deficits. Matters are made worse if the child is sitting in the back of the classroom away from the teacher.

Data shows that in the classroom situation, better hearing occurs when the teacher's voice is 20 dB louder than the environmental background noise. One way to achieve the increase in loudness is to utilize a wireless FM Trainer System, such as the iSense, in which the teacher wears a microphone, and the student wears an ear level FM receiver that places the teacher's voice directly into their ear. Because the iSense uses FM signal transmission, there are no wires connecting the teacher with the student. The iSense is also readily accepted by most students because it is small, inconspicuous, and has a contemporary, high-tech design. This is in contrast to older classroom FM Trainer Systems which looked more like a Sony Walkman with a large, conspicuous, headband headset.

If you would like to learn more about the iSense Dynamic FM System from Phonak, please contact our office at (336) 273-9932 and ask to speak to one of our Audiologists. You may also visit Phonak's web site at www.phonak.com.


  1. The Link to Learn: Edulink. Phonak Hearing Systems, 2006.

Last revised January 8, 2011