title: When synesthesia and savant abilities are mistaken for hallucinations and delusions: contribution of a cognitive approach for their differential diagnosis.
abstract: OBJECTIVE
  Schizophrenia is characterized by hallucinations, delusions, disorganized speech and behavior, and other symptoms that cause social or occupational dysfunction. However, some of these symptoms, such as hallucinations and delusions, can be indicative of other phenomena such as synesthesia and savant abilities. The aim of this paper is to highlight how neurological and psychiatric conditions can be confused and how formal neuropsychological evaluations can be necessary to distinguish them.
  
  
  METHODS
  We report the case of a young woman, VA, who perceived sounds as colors and claimed to have elaborated complex astrophysical reasoning, despite having experienced difficulties at school, especially in mathematics. VA also had difficulties to orient herself, to develop social relationships, and often became confused by daily life situations. These elements were considered as symptoms of schizophrenia.
  
  
  RESULTS
  Evaluations revealed that VA exhibited savant abilities in astrophysics and colored-hearing synesthesia. We also found evidence of higher-than-average cognitive functioning.
  
  
  CONCLUSIONS
  In complex cases, neuropsychological and formal evaluations are necessary to establish a differential diagnosis. Moreover, the case highlights the link between synesthesia and savant abilities.
authors.affiliation: a Laboratoire CERPPS (EA 7411) , Université Toulouse Jean Jaurés , Toulouse , France.
authors.forename: Lucie
authors.initials: L
authors.lastname: Bouvet
authors.affiliation: b Syndicat national des Psychiatres Privés , Reims , France.
authors.forename: Jacques-Edouard
authors.initials: JE
authors.lastname: Barbier
authors.affiliation: c Laboratoire PSITEC (EA 4072) , Université de Lille 3 , Lille , France.
authors.forename: Nia
authors.initials: N
authors.lastname: Cason
authors.affiliation: d Service de neurologie, Hôpital Maison-Blanche , Hôpital Universitaire de Reims , Reims , France.
authors.forename: Serge
authors.initials: S
authors.lastname: Bakchine
authors.affiliation: c Laboratoire PSITEC (EA 4072) , Université de Lille 3 , Lille , France.|d Service de neurologie, Hôpital Maison-Blanche , Hôpital Universitaire de Reims , Reims , France.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Ehrlé
mesh_terms: D000328:Adult; D003072:Cognition Disorders / Q000175:diagnosis*; D003702:Delusions / Q000175:diagnosis*; D003937:Diagnosis, Differential; D005260:Female; D006212:Hallucinations / Q000175:diagnosis*; D006801:Humans; D009483:Neuropsychological Tests; D010468:Perceptual Disorders / Q000175:diagnosis*; D012565:Schizophrenic Psychology; D000080311:Synesthesia
keywords: Schizophrenia; differential diagnosis; savant abilities; synesthesia