title: Behavioral sensitivity to changing reinforcement contingencies in attention-deficit hyperactivity disorder.
abstract: Altered sensitivity to positive reinforcement has been hypothesized to contribute to the symptoms of attention-deficit hyperactivity disorder (ADHD). In this study, we evaluated the ability of children with and without ADHD to adapt their behavior to changing reinforcer availability.
  
  
  
  Of one hundred sixty-seven children, 97 diagnosed with ADHD completed a signal-detection task in which correct discriminations between two stimuli were associated with different frequencies of reinforcement. The response alternative associated with the higher rate of reinforcement switched twice during the task without warning. For a subset of participants, this was followed by trials for which no reinforcement was delivered, irrespective of performance.
  
  
  
  Children in both groups developed an initial bias toward the more frequently reinforced response alternative. When the response alternative associated with the higher rate of reinforcement switched, the children's response allocation (bias) followed suit, but this effect was significantly smaller for children with ADHD. When reinforcement was discontinued, only children in the control group modified their response pattern.
  
  
  
  Children with ADHD adjust their behavioral responses to changing reinforcer availability less than typically developing children, when reinforcement is intermittent and the association between an action and its consequences is uncertain. This may explain the difficulty children with ADHD have adapting their behavior to new situations, with different reinforcement contingencies, in daily life.
authors.affiliation: Department of Psychology, University of Otago, Dunedin, New Zealand.
authors.forename: Brent
authors.initials: B
authors.lastname: Alsop
authors.affiliation: Okinawa Institute of Science and Technology Graduate University, Onna, Japan.
authors.forename: Emi
authors.initials: E
authors.lastname: Furukawa
authors.affiliation: Child and Adolescent Mental Health Services, Blenheim, New Zealand.
authors.forename: Paula
authors.initials: P
authors.lastname: Sowerby
authors.affiliation: Department of Psychology, University of Otago, Dunedin, New Zealand.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Jensen
authors.affiliation: Psychology Associates, Dunedin, New Zealand.
authors.forename: Cara
authors.initials: C
authors.lastname: Moffat
authors.affiliation: Okinawa Institute of Science and Technology Graduate University, Onna, Japan.
authors.forename: Gail
authors.initials: G
authors.lastname: Tripp
mesh_terms: D001289:Attention Deficit Disorder with Hyperactivity / Q000503:physiopathology*; D002648:Child; D002652:Child Behavior / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D011597:Psychomotor Performance / Q000502:physiology*; D012054:Reinforcement, Psychology; D017603:Signal Detection, Psychological / Q000502:physiology*
keywords: Attention-deficit hyperactivity disorder; change; reinforcement; response allocation