Central Auditory processing disorder (CAPD), also known as Auditory Processing Disorder (APD), is an umbrella term for a variety of disorders that affect the way the brain processes auditory information. Individuals with CAPD usually have normal structure and function of the outer, middle and inner ear (peripheral hearing). However, they cannot process the information they hear in the same way as others do, which leads to difficulties in recognizing and interpreting sounds, especially the sounds composing speech. It is thought that these difficulties arise from dysfunction in the central nervous system.
Central auditory processing disorders can be developmental or acquired. It may result from ear infections, head injuries or neurodevelopmental delays that affect processing of auditory information. This can include problems with: sound localization and lateralization; auditory discrimination; auditory pattern recognition; temporal aspects of audition, including temporal integration, temporal discrimination (e.g., temporal gap detection), temporal ordering, and temporal masking; auditory performance in competing acoustic signals (including dichotic listening); and auditory performance with degraded acoustic signals. It is thought that these difficulties arise from dysfunction in the central nervous system.