Also known as Central Auditory Processing Disorder, this is a condition that negatively affects how sound that travels unimpeded through the ear (normal hearing ) is processed or interpreted by the brain.

Individuals with APD do not recognize subtle differences between sounds in words, even when the sounds are loud and clear enough to be heard. They can also find it difficult to tell where sounds are coming from, to make sense of the order of sounds, or to block out competing for background noises.