title: Apraxia of speech and cerebellar mutism syndrome: a case report.
abstract: BACKGROUND
  Cerebellar mutism syndrome (CMS) or posterior fossa syndrome (PFS) consists of a constellation of neuropsychiatric, neuropsychological and neurogenic speech and language deficits. It is most commonly observed in children after posterior fossa tumor surgery. The most prominent feature of CMS is mutism, which generally starts after a few days after the operation, has a limited duration and is typically followed by motor speech deficits. However, the core speech disorder subserving CMS is still unclear.
  
  
  METHODS
  This study investigates the speech and language symptoms following posterior fossa medulloblastoma surgery in a 12-year-old right-handed boy. An extensive battery of formal speech (DIAS = Diagnostic Instrument Apraxia of Speech) and language tests were administered during a follow-up of 6 weeks after surgery. Although the neurological and neuropsychological (affective, cognitive) symptoms of this patient are consistent with Schmahmann's syndrome, the speech and language symptoms were markedly different from what is typically described in the literature. In-depth analyses of speech production revealed features consistent with a diagnosis of apraxia of speech (AoS) while ataxic dysarthria was completely absent. In addition, language assessments showed genuine aphasic deficits as reflected by distorted language production and perception, wordfinding difficulties, grammatical disturbances and verbal fluency deficits.
  
  
  CONCLUSIONS
  To the best of our knowledge this case might be the first example that clearly demonstrates that a higher level motor planning disorder (apraxia) may be the origin of disrupted speech in CMS. In addition, identification of non-motor linguistic disturbances during follow-up add to the view that the cerebellum not only plays a crucial role in the planning and execution of speech but also in linguistic processing. Whether the cerebellum has a direct or indirect role in motor speech planning needs to be further investigated.
authors.affiliation: Clinical and Experimental Neurolinguistics, CLIN, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium.
authors.forename: E
authors.initials: E
authors.lastname: De Witte
authors.affiliation: Department of Speech and Language Therapy, ZNA Middelheim, Lindendreef 1, B-2020 Antwerp, Belgium.
authors.forename: I
authors.initials: I
authors.lastname: Wilssens
authors.affiliation: Department of Radiology, ZNA Middelheim, Lindendreef 1, B-2020 Antwerp, Belgium.
authors.forename: D
authors.initials: D
authors.lastname: De Surgeloose
authors.affiliation: Department of Neurosurgery, ZNA Middelheim, Lindendreef 1, B-2020 Antwerp, Belgium.
authors.forename: G
authors.initials: G
authors.lastname: Dua
authors.affiliation: Department of Neurosurgery and Center for Neuroscience, Universitair Ziekenhuis Brussel, Laarbeeklaan 101, B-1090 Brussels, Belgium.
authors.forename: M
authors.initials: M
authors.lastname: Moens
authors.affiliation: Department of Language and Communication Science, City University London, Northampton Square, London, EC1V 0HB UK.
authors.forename: J
authors.initials: J
authors.lastname: Verhoeven
authors.affiliation: Unité d'Etude du Mouvement, FNRS-ULB, Bruxelles, Belgium.
authors.forename: M
authors.initials: M
authors.lastname: Manto
authors.affiliation: Clinical and Experimental Neurolinguistics, CLIN, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium ; Department of Neurology & Memory Clinic, ZNA Middelheim Hospital, Lindendreef 1, B-2020 Antwerp, Belgium.
authors.forename: P
authors.initials: P
authors.lastname: Mariën
keywords: Apraxia of speech; Ataxic dysarthria; Case report; Cerebellar mutism syndrome; Cerebellum; Medulloblastoma; Posterior fossa