title: Attentional Networks in Adolescents with High-functioning Autism: An fMRI Investigation.
abstract: BACKGROUND
  Attentional deficits in Autism spectrum disorder (ASD) are often noted, but their specific nature remains unclear.
  
  
  OBJECTIVE
  The present study used the child Attentional Network Task (Child ANT) in combination with functional magnetic resonance imaging (fMRI) to determine if the consistently cited deficits of orienting attention are truly due to dysfunctions of orienting-based networks. We hypothesized that these observations are, in fact, a reflection of executive dysfunctions. As such, we expected that although ASD adolescents would perform worse on the orienting portion of the Child ANT, the strongest differences in activation between them and the neurotypical (NT) control group would be in areas classically associated with executive functioning (e.g., the frontal gyri and anterior cingulate cortex).
  
  
  METHODS
  The brain activity of six high-functioning adolescents with ASD and six NT adolescents was recorded while these individuals performed the three subcomponents of the Child ANT.
  
  
  RESULTS
  ASDs were shown to be more accurate than NTs for the alerting, less accurate for the orienting, and similar in accuracy for the executive portions of the Child ANT. fMRI data showed increased bilateral frontal gyri recruitment, areas conventionally associated with executive control, during the orienting task for the ASD group.
  
  
  CONCLUSIONS
  We submit that the increased activations represent neurocorrelates of signal fixation attributable to the subset of executive control responsible for sustained maintenance signals, not the main components of orienting. Therefore, excessive fixation in ASD adolescents is likely due to dysfunctions of executive control and not the orienting subcomponent of the attention network.
authors.affiliation: Department of Electrical and Computer Engineering, Texas Tech University, Lubbock, TX 79409, USA.
authors.forename: Elizabeth C
authors.initials: EC
authors.lastname: Hames
authors.affiliation: Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA.
authors.forename: Ravi
authors.initials: R
authors.lastname: Rajmohan
authors.affiliation: College of Human Sciences, Texas Tech University, Lubbock, TX 79409, USA.
authors.forename: Dan
authors.initials: D
authors.lastname: Fang
authors.affiliation: Department of Electrical and Computer Engineering, Texas Tech University, Lubbock, TX 79409, USA.
authors.forename: Ronald
authors.initials: R
authors.lastname: Anderson
authors.affiliation: Department of Electrical and Computer Engineering, Texas Tech University, Lubbock, TX 79409, USA.
authors.forename: Mary
authors.initials: M
authors.lastname: Baker
authors.affiliation: College of Education, Texas Tech University, Lubbock, TX 79409, USA.
authors.forename: David M
authors.initials: DM
authors.lastname: Richman
authors.affiliation: College of Human Sciences, Texas Tech University, Lubbock, TX 79409, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: O'Boyle
keywords: ASD; Adolescents; Attention; Executive control; FMRI; High-functioning autism