title: Intrinsic Brain Connectivity Following Long-Term Treatment with Methylphenidate in Children with Attention-Deficit/Hyperactivity Disorder.
abstract: Although widely used for the treatment of attention-deficit/hyperactivity disorder (ADHD) across the life span, the effects of methylphenidate (MPH) on the brain are not completely understood. Functional neuroimaging techniques may help increase knowledge about the mechanisms of MPH action.
  
  
  
  To evaluate changes in functional connectivity patterns of the default mode network (DMN) in children with ADHD following long-term treatment with MPH.
  
  
  
  Twenty-three right-handed treatment-naïve boys with ADHD underwent a protocol of intrinsic functional connectivity before and after 6 months of treatment with MPH. Functional connectivity was analyzed using a region of interest (ROI) approach and independent component analysis (ICA).
  
  
  
  ROI analyses showed no significant changes in connectivity between regions of the DMN following treatment, with a relatively small increase in the anterior-posterior connectivity of the network. ICA revealed a significant increase in connectivity between the left putamen and the DMN (p < 0.001, corrected). There was a correlation between the reduction of symptoms and the increased connectivity between the putamen and the DMN after treatment (rho = -0.65, p = 0.017).
  
  
  
  Dysfunctions in cortical-subcortical circuits have often been associated with the pathophysiology of ADHD. Our findings suggest that effective treatment with MPH in children with ADHD may affect brain functioning by increasing connectivity between the DMN and subcortical nuclei.
authors.affiliation: 1 Department of Psychiatry, Hospital de Clínicas de Porto Alegre , Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil .
authors.forename: Lucas
authors.initials: L
authors.lastname: Battel
authors.affiliation: 1 Department of Psychiatry, Hospital de Clínicas de Porto Alegre , Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil .
authors.forename: Renata R
authors.initials: RR
authors.lastname: Kieling
authors.affiliation: 1 Department of Psychiatry, Hospital de Clínicas de Porto Alegre , Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil .
authors.forename: Christian
authors.initials: C
authors.lastname: Kieling
authors.affiliation: 1 Department of Psychiatry, Hospital de Clínicas de Porto Alegre , Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil .|2 Brain Institute (InsCer) , PUCRS, Porto Alegre, Brazil .
authors.forename: Maurício
authors.initials: M
authors.lastname: Anés
authors.affiliation: 3 National Institute of Developmental Psychiatry for Children and Adolescents , Porto Alegre, Brazil .
authors.forename: Nathassia Kadletz
authors.initials: NK
authors.lastname: Aurich
authors.affiliation: 2 Brain Institute (InsCer) , PUCRS, Porto Alegre, Brazil .
authors.forename: Jaderson Costa
authors.initials: JC
authors.lastname: da Costa
authors.affiliation: 1 Department of Psychiatry, Hospital de Clínicas de Porto Alegre , Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil .|3 National Institute of Developmental Psychiatry for Children and Adolescents , Porto Alegre, Brazil .
authors.forename: Luis Augusto
authors.initials: LA
authors.lastname: Rohde
authors.affiliation: 2 Brain Institute (InsCer) , PUCRS, Porto Alegre, Brazil .|4 School of Engineering , PUCRS, Porto Alegre, Brazil .
authors.forename: Alexandre Rosa
authors.initials: AR
authors.lastname: Franco
mesh_terms: D001289:Attention Deficit Disorder with Hyperactivity / Q000188:drug therapy* / Q000503:physiopathology; D001921:Brain / Q000000981:diagnostic imaging / Q000187:drug effects*; D000697:Central Nervous System Stimulants / Q000008:administration & dosage / Q000494:pharmacology*; D002648:Child; D007839:Functional Laterality / Q000502:physiology; D059907:Functional Neuroimaging / Q000379:methods; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008774:Methylphenidate / Q000008:administration & dosage / Q000494:pharmacology*; D009415:Nerve Net / Q000000981:diagnostic imaging; D013997:Time Factors
chemical_list: D000697:Central Nervous System Stimulants; D008774:Methylphenidate