To hear when there is more than one sound present we need to be able to disregard some sounds and concentrate on others. Both ears need to contribute in challenging listening conditions but our hearing system can’t work optimally if one ear dominates. 

In “dichotic” tests, different information is played to the two ears simultaneously.  Many children with APD score lower in one ear on dichotic tests (amblyaudia).  Usually the left ear is the weak one. The hearing centres and pathways associated with the dominant ear may actually be suppressing the weak ear. 

SoundSkills audiologists carry out specialised testing to detect amblyaudia.  Fortunately amblyaudia can be improved or fully corrected with one month of specialised auditory training (Moncrieff and Wertz, 2008).