title: Attentional regulation in young twins with probable stuttering, high nonfluency, and typical fluency.
abstract: OBJECTIVE
  Using a sample of 20,445 Dutch twins, this study examined the relationship between speech fluency and attentional regulation in children. A secondary objective was to identify etiological overlap between nonfluency and poor attention using fluency-discordant twin pairs.
  
  
  METHODS
  Three fluency groups were created at age 5 using a parent questionnaire: (a) probable stuttering (PS; N=826; 4.0%), highly nonfluent (HNF; N=547; 2.7%), and typically fluent (TF; N=19,072; 93%). Multiple scales assessing attention, primarily self-regulation/inhibition, were obtained from both parents when children were ages 5 and 7 and from teachers when children were age 7.
  
  
  RESULTS
  When compared with the TF controls, both the PS and HNF children received higher (i.e., more problematic) scores on parental attention ratings at both ages (p<.002). Effect sizes were moderate for both groups. Teacher and parent ratings were generally comparable. The discordant co-twin analyses suggested that nonfluency and attention were influenced by potentially overlapping genetic and shared environmental factors.
  
  
  CONCLUSIONS
  The liability to express both high nonfluency and problems with self-regulation/inhibition may arise from a common set of pathogenic mechanisms. This supports emerging models of stuttering, which propose that poor fluency may be part of a broader network of impaired self-regulatory processes.
authors.affiliation: Department of Communication Disorders, Southern Connecticut State University, 501 Crescent Street, New Haven, CT 06515-1330, USA. felsenfelds1@southernct.edu
authors.forename: Susan
authors.initials: S
authors.lastname: Felsenfeld
authors.forename: Catharina Eugenie Maria
authors.initials: CE
authors.lastname: van Beijsterveldt
authors.forename: Dorret Irene
authors.initials: DI
authors.lastname: Boomsma
mesh_terms: D001288:Attention / Q000502:physiology*; D001289:Attention Deficit Disorder with Hyperactivity / Q000150:complications* / Q000523:psychology; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D004200:Diseases in Twins; D056344:Executive Function / Q000502:physiology*; D005260:Female; D006801:Humans; D007266:Inhibition, Psychological; D008137:Longitudinal Studies; D008297:Male; D012016:Reference Values; D020377:Self Efficacy; D013060:Speech / Q000502:physiology*; D013068:Speech Production Measurement; D013342:Stuttering / Q000150:complications* / Q000503:physiopathology / Q000523:psychology