BACKGROUND: The ability to inhibit motor responses, as assessed by the stop-signal reaction time (SSRT), is impaired in children and adolescents with attention-deficit/hyperactivity disorder (ADHD). However, the between-study variation in effect sizes is large. The aim of this study was to investigate whether this variability can be explained by between-study variation in Go task complexity. METHOD: Forty-one studies comparing children or adolescents diagnosed with ADHD to normal control subjects were incorporated in a random-effects meta-regression analysis. The independent variables were a global index of Go task complexity (i.e., mean reaction time in control subjects [RTc]) and a more specific index (i.e., spatial compatibility of the stimulus-response mapping). The dependent variable was the SSRT difference between ADHD and control subjects. RESULTS: The SSRT difference increased significantly with increasing RTc. Moreover, the SSRT difference was significantly increased in studies that employed a noncompatible, that is, arbitrary, mapping compared with studies that incorporated a spatially compatible stimulus-response mapping. CONCLUSIONS: These results indicate that inhibitory dysfunction in children and adolescents with ADHD varies with task complexity: inhibitory dysfunction in ADHD is most pronounced for spatially noncompatible responses. Explanations in terms of inhibition and working memory deficits and a tentative neurobiological explanation are briefly discussed.
BACKGROUND: The ability to inhibit motor responses, as assessed by the stop-signal reaction time (SSRT), is impaired in children and adolescents with attention-deficit/hyperactivity disorder (ADHD). However, the between-study variation in effect sizes is large. The aim of this study was to investigate whether this variability can be explained by between-study variation in Go task complexity. METHOD: Forty-one studies comparing children or adolescents diagnosed with ADHD to normal control subjects were incorporated in a random-effects meta-regression analysis. The independent variables were a global index of Go task complexity (i.e., mean reaction time in control subjects [RTc]) and a more specific index (i.e., spatial compatibility of the stimulus-response mapping). The dependent variable was the SSRT difference between ADHD and control subjects. RESULTS: The SSRT difference increased significantly with increasing RTc. Moreover, the SSRT difference was significantly increased in studies that employed a noncompatible, that is, arbitrary, mapping compared with studies that incorporated a spatially compatible stimulus-response mapping. CONCLUSIONS: These results indicate that inhibitory dysfunction in children and adolescents with ADHD varies with task complexity: inhibitory dysfunction in ADHD is most pronounced for spatially noncompatible responses. Explanations in terms of inhibition and working memory deficits and a tentative neurobiological explanation are briefly discussed.
Authors: Denis G Sukhodolsky; Angeli Landeros-Weisenberger; Lawrence Scahill; James F Leckman; Robert T Schultz Journal: J Am Acad Child Adolesc Psychiatry Date: 2010-11 Impact factor: 8.829
Authors: Kristen R Hamilton; Andrew K Littlefield; Noelle C Anastasio; Kathryn A Cunningham; Latham H L Fink; Victoria C Wing; Charles W Mathias; Scott D Lane; Christian G Schütz; Alan C Swann; C W Lejuez; Luke Clark; F Gerard Moeller; Marc N Potenza Journal: Personal Disord Date: 2015-04
Authors: Mikael Cavallet; Tiffany M Chaim-Avancini; Claudinei E Biazoli; Paulo R Bazán; Maria Aparecida da Silva; Paulo Jannuzzi Cunha; Carmen S Miguel; Geraldo F Busatto; Mario R Louzã; Luiz G Gawryszewski Journal: Exp Brain Res Date: 2016-07-07 Impact factor: 1.972
Authors: Anne H Udal; Ulrik F Malt; Hans Lövdahl; Bente Gjaerum; Are H Pripp; Berit Groholt Journal: Behav Brain Funct Date: 2009-12-10 Impact factor: 3.759
Authors: Hilde M Huizenga; Maurits W van der Molen; Anika Bexkens; Marieke G N Bos; Wery P M van den Wildenberg Journal: Front Psychol Date: 2012-05-08