Most children suffering from hearing loss are subject to the auditory brain stem response test that is also known as ABR hearing test. In this procedure small ear phones suitable for children are placed in the outer ear in order to start recording the results.
In this ABR hearing test, electrodes are also placed behind the ear and on the forehead in order to record responses from the auditory nerves. After this small click type sounds are generated in the ear phones and the responses of the auditory nerves are recorded with the aid of a computer.
Since children have very small attention span, it may is very difficult to hold them in place while conduction the test therefore they are sedated while conducting the ABR hearing test.
When there is high intensity sound in the environment, it leads to various stapedial reflexes in the middle ear of humans. The stapedial reflexes are also referred to as acoustic reflex or attenuation reflex or auditory reflex.
During the ABR hearing test the stapedius and tensor tympani muscles in the ossicles contract. Thus as a result of this action the stapes or stirrup as it is commonly known, contracts and pulls away from the oval window of the cochlea.
The tensor tympani muscle also pulls the hammer away from the ear drum. Thus as a result of the ABR hearing test the vibrating sound energy is converted into electrical impulses that are transmitted to the central nervous system.