Dysfunctions of visual and auditory Gestalt perception (amusia) after stroke : Behavioral correlates and functional magnetic resonance imaging

Music is a special and unique part of human nature. Not only actively playing (making music in a group or alone) but also passive listening to music involves a richness of processes to make music the ideal tool to investigate how the human brain works. Acquired amusia denotes the impaired perception of melodies, rhythms, and the associated disability to enjoy music which can occur after a stroke. Many amusia patients also show deficits in visual perception, language, memory, and attention. Hence, the question arises whether amusia actually describes an independent clinical picture or is better described by a general perceptual deficit for auditory, as well as visual, and speech-related material. Additionally, the question in what way impaired abilities in attention and working memory influence the performance in the music perception task remains to be investigated. Behavioral investigations, lesion analysis, and functional magnetic resonance imaging were performed to assess the anatomical and functional correlates of these deficits. A better and more detailed understanding of amusia and connected cognitive deficits is not only relevant in terms of fundamental neuroscience but also from a clinical point of view: symptoms of amusia are rare, mostly undiscovered, and the underlying mechanisms are hitherto insufficiently understood.