title: Neuropsychological function in children with primary complex motor stereotypies.
abstract: OBJECTIVE
  Complex motor stereotypies (CMS) are patterned, repetitive, rhythmic, and involuntary movements that persist over time. They are divided into two subgroups dependent on the presence of other developmental problems: 'primary' (development is otherwise typical) or 'secondary' (associated with autism, intellectual disability, or sensory deficits). There are no currently published studies that examine neuropsychological function in children with primary CMS. This case-control study examines whether children with primary CMS manifest neurobehavioral deficits.
  
  
  METHODS
  Fifty-seven children with primary CMS (32 males, 25 females; mean age 6y 8mo, SD 2y 4mo, range 4-12y) with negative screens for autism and 57 comparison participants (32 males, 25 females; mean age 6y 6mo, SD 2y 1mo) completed neuropsychological assessments of IQ, reading ability, attention, language, and motor and executive functions. Parents completed ratings of their child's repetitive movement severity.
  
  
  RESULTS
  The CMS group performed significantly less well than comparison participants on motor skills and IQ tests (both p<0.01), although IQ was consistently in the average range. One-third of the CMS group showed signs of developmental motor coordination difficulties. Parent report of stereotypy severity was significantly associated with parent report of inattention and executive dysfunction.
  
  
  CONCLUSIONS
  Children with primary CMS were found to have largely intact neuropsychological profiles. Stereotypy severity appears to be associated with executive dysfunction. Although motor difficulties were observed in children with CMS, these were not correlated with parent report of symptom severity.
authors.affiliation: Department of Neuropsychology, Kennedy Krieger Institute, Baltimore, MD, USA.
authors.forename: E Mark
authors.initials: EM
authors.lastname: Mahone
authors.forename: Matthew
authors.initials: M
authors.lastname: Ryan
authors.forename: Lisa
authors.initials: L
authors.lastname: Ferenc
authors.forename: Christina
authors.initials: C
authors.lastname: Morris-Berry
authors.forename: Harvey S
authors.initials: HS
authors.lastname: Singer
mesh_terms: D016022:Case-Control Studies; D002648:Child; D002652:Child Behavior / Q000502:physiology*; D002675:Child, Preschool; D056344:Executive Function / Q000502:physiology*; D005260:Female; D006801:Humans; D007360:Intelligence / Q000502:physiology; D008297:Male; D009048:Motor Skills / Q000502:physiology; D009069:Movement Disorders / Q000503:physiopathology*; D009483:Neuropsychological Tests / Q000592:standards*; D015203:Reproducibility of Results; D012720:Severity of Illness Index