Amusia is a musical disorder that appears mainly as a defect in processing pitch, but it also encompasses musical memory and recognition. Two main classifications of amusia exist: acquired amusia, which occurs as a result of brain damage, and congenital amusia, which results from a music processing anomaly at birth.Studies have shown that congenital amusia is a deficit in fine-grained pitch discrimination and that 4% of the population suffers from this disorder. Acquired amusia, on the other hand, may take several forms. Patients with brain damage may experience the loss of ability to produce musical sounds while sparing speech, much like aphasics lose speech selectively but can sometimes still sing. Other forms of amusia may affect specific sub-processes of music processing. Current research has demonstrated dissociations between rhythm, melody, and emotional processing of music, and amusia may include impairment of any combination of these skill sets.