title: Neural Basis of Acquired Amusia and Its Recovery after Stroke.
abstract: Although acquired amusia is a relatively common disorder after stroke, its precise neuroanatomical basis is still unknown. To evaluate which brain regions form the neural substrate for acquired amusia and its recovery, we performed a voxel-based lesion-symptom mapping (VLSM) and morphometry (VBM) study with 77 human stroke subjects. Structural MRIs were acquired at acute and 6 month poststroke stages. Amusia and aphasia were behaviorally assessed at acute and 3 month poststroke stages using the Scale and Rhythm subtests of the Montreal Battery of Evaluation of Amusia (MBEA) and language tests. VLSM analyses indicated that amusia was associated with a lesion area comprising the superior temporal gyrus, Heschl's gyrus, insula, and striatum in the right hemisphere, clearly different from the lesion pattern associated with aphasia. Parametric analyses of MBEA Pitch and Rhythm scores showed extensive lesion overlap in the right striatum, as well as in the right Heschl's gyrus and superior temporal gyrus. Lesions associated with Rhythm scores extended more superiorly and posterolaterally. VBM analysis of volume changes from the acute to the 6 month stage showed a clear decrease in gray matter volume in the right superior and middle temporal gyri in nonrecovered amusic patients compared with nonamusic patients. This increased atrophy was more evident in anterior temporal areas in rhythm amusia and in posterior temporal and temporoparietal areas in pitch amusia. Overall, the results implicate right temporal and subcortical regions as the crucial neural substrate for acquired amusia and highlight the importance of different temporal lobe regions for the recovery of amusia after stroke.
  
  
  
  Lesion studies are essential in uncovering the brain regions causally linked to a given behavior or skill. For music perception ability, previous lesion studies of amusia have been methodologically limited in both spatial accuracy and time domain as well as by small sample sizes, providing coarse and equivocal information about which brain areas underlie amusia. By using longitudinal MRI and behavioral data from a large sample of stroke patients coupled with modern voxel-based analyses methods, we were able provide the first systematic evidence for the causal role of right temporal and striatal areas in music perception. Clinically, these results have important implications for the diagnosis and prognosis of amusia after stroke and for rehabilitation planning.
authors: Faculty of Medicine, University of Turku, 20520 Turku, Finland, Cognitive Brain Research Unit, Institute of Behavioural Sciences, University of Helsinki, 00014 Helsinki, Finland, ajsihv@utu.fi.
authors: Aleksi J
authors: 0000-0002-4501-7338
authors: AJ
authors: Sihvonen
authors: Cognition and Brain Plasticity Group, Bellvitge Biomedical Research Institute, L'Hospitalet de Llobregat, 08907 Barcelona, Spain, Department of Basic Psychology, University of Barcelona, 08035 Barcelona, Spain, and.
authors: Pablo
authors: 0000-0002-8463-3723
authors: P
authors: Ripollés
authors: Cognitive Brain Research Unit, Institute of Behavioural Sciences, University of Helsinki, 00014 Helsinki, Finland.
authors: Vera
authors: V
authors: Leo
authors: Cognition and Brain Plasticity Group, Bellvitge Biomedical Research Institute, L'Hospitalet de Llobregat, 08907 Barcelona, Spain, Department of Basic Psychology, University of Barcelona, 08035 Barcelona, Spain, and.
authors: Antoni
authors: 0000-0002-3249-6931
authors: A
authors: Rodríguez-Fornells
authors: Division of Clinical Neurosciences, Turku University Hospital and Department of Neurology, University of Turku, 20521, Turku, Finland.
authors: Seppo
authors: S
authors: Soinila
authors: Cognitive Brain Research Unit, Institute of Behavioural Sciences, University of Helsinki, 00014 Helsinki, Finland.
authors: Teppo
authors: 0000-0002-1470-4530
authors: T
authors: Särkämö
mesh_terms: D000368:Aged; D001308:Auditory Perceptual Disorders / Q000000981:diagnostic imaging / Q000209:etiology* / Q000534:rehabilitation*; D001931:Brain Mapping; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007806:Language Disorders / Q000000981:diagnostic imaging / Q000209:etiology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D020768:Middle Cerebral Artery / Q000000981:diagnostic imaging; D020127:Recovery of Function / Q000502:physiology*; D012189:Retrospective Studies; D020521:Stroke / Q000150:complications*
keywords: amusia; aphasia; music; stroke; voxel-based lesion-symptom mapping; voxel-based morphometry