title: Examining pitch and numerical magnitude processing in congenital amusia: A quasi-experimental pilot study.
abstract: BACKGROUND
  Congenital amusia is a developmental disorder associated with deficits in pitch height discrimination or in integrating pitch sequences into melodies. This quasi-experimental pilot study investigated whether there is an association between pitch and numerical processing deficits in congenital amusia. Since pitch height discrimination is considered a form of magnitude processing, we investigated whether individuals with amusia present an impairment in numerical magnitude processing, which would reflect damage to a generalized magnitude system. Alternatively, we investigated whether the numerical processing deficit would reflect a disconnection between nonsymbolic and symbolic number representations.
  
  
  METHODS
  This study was conducted with 11 adult individuals with congenital amusia and a control comparison group of 6 typically developing individuals. Participants performed nonsymbolic and symbolic magnitude comparisons and number line tasks. Results were available from previous testing using the Montreal Battery of Evaluation of Amusia (MBEA) and a pitch change detection task (PCD).
  
  
  RESULTS
  Compared to the controls, individuals with amusia exhibited no significant differences in their performance on both the number line and the nonsymbolic magnitude tasks. Nevertheless, they showed significantly worse performance on the symbolic magnitude task. Moreover, individuals with congenital amusia, who presented worse performance in the Meter subtest, also presented less precise nonsymbolic numerical representation.
  
  
  CONCLUSIONS
  The relationship between meter and nonsymbolic numerical discrimination could indicate a general ratio processing deficit. The finding of preserved nonsymbolic numerical magnitude discrimination and mental number line representations, with impaired symbolic number processing, in individuals with congenital amusia indicates that (a) pitch height and numerical magnitude processing may not share common neural representations, and (b) in addition to pitch processing, individuals with amusia may present a deficit in accessing nonsymbolic numerical representations from symbolic representations. The symbolic access deficit could reflect a widespread impairment in the establishment of cortico-cortical connections between association areas.
authors.affiliation: a Developmental Neuropsychology Laboratory (LND), Department of Psychology , Universidade Federal de Minas Gerais , Belo Horizonte , Brazil.|b Programa de Pós-Graduação em Neurociências , Universidade Federal de Minas Gerais , Belo Horizonte , Brazil.
authors.forename: Marilia
authors.initials: M
authors.lastname: Nunes-Silva
authors.affiliation: a Developmental Neuropsychology Laboratory (LND), Department of Psychology , Universidade Federal de Minas Gerais , Belo Horizonte , Brazil.|b Programa de Pós-Graduação em Neurociências , Universidade Federal de Minas Gerais , Belo Horizonte , Brazil.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Moura
authors.affiliation: a Developmental Neuropsychology Laboratory (LND), Department of Psychology , Universidade Federal de Minas Gerais , Belo Horizonte , Brazil.|c Programa de Pós-Graduação em Saúde da Criança e do Adolescente, Faculdade de Medicina , Universidade Federal de Minas Gerais , Belo Horizonte , Brazil.
authors.forename: Júlia Beatriz
authors.initials: JB
authors.lastname: Lopes-Silva
authors.affiliation: a Developmental Neuropsychology Laboratory (LND), Department of Psychology , Universidade Federal de Minas Gerais , Belo Horizonte , Brazil.|b Programa de Pós-Graduação em Neurociências , Universidade Federal de Minas Gerais , Belo Horizonte , Brazil.
authors.forename: Vitor Geraldi
authors.initials: VG
authors.lastname: Haase
mesh_terms: D000368:Aged; D001308:Auditory Perceptual Disorders / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D055641:Mathematical Concepts; D008875:Middle Aged; D010865:Pilot Projects; D010898:Pitch Perception / Q000502:physiology*
keywords: Congenital amusia; Magnitude; Modularity; Music; Number sense