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Cortical Auditory Evoked Potentials
The Cortical Auditory Evoked Potentials (CAEP) test provides information about the reception of sound by a child. It may be used as an additional assessment if required.

This test is useful in helping LOCHI audiologists to provide effective amplification for children for whom there is uncertainty about their hearing levels. The CAEP has also been used in the Frequency Compression study (featured on Parents page) to determine whether the new hearing aids improved children’s ability to hear sounds.
Evoked potentials are small electrical signals produced by the hearing pathways in response  to sounds. The signals are recorded from the surface of the head by using electrodes. Three small sensors (electrodes) are attached to the surface of the child’s forehead, top of the head and behind the ear.

During the test, the child wears his/her hearing aids/ cochlear implant. Several different speechsounds (/m/, /g/, /t/ and /s/) are presented through a loudspeaker at different levels.  The brainwaves are recorded from the surface of the head via electrodes. The recorded brain waves are then analysed by the software to reveal whether the speech sounds elicited responses at the cortical level. The presence of CAEPs to speech stimuli provides objective evidence that these sounds have arrived at the cortex and are potentially audible to the child with hearing aids or cochlea implants. 

The child should be relaxed and comfortable while being tested. Generally, testing may take up to an hour.  During that time, the child can watch a DVD or read a book.