title: Elevated background noise in adult attention deficit hyperactivity disorder is associated with inattention.
abstract: BACKGROUND
  Inattention and distractibility are core symptoms of attention deficit hyperactivity disorder (ADHD). Still the neuronal organization is largely unknown. Previously we studied the electrophysiological activity of a distinct neuronal network-the retina-and found no change in stimulus-driven neural activity in patients with ADHD. However there is growing evidence for an elevated non stimulus-driven neural activity, or neuronal background noise, as underlying pathophysiological correlate. To further examine the biological bases that might underlie ADHD and problems with inattention, we performed a new analysis to test the hypothesis of an elevated background noise as underlying neuronal correlate for ADHD and problems with inattention in humans. A direct measure of background noise in patients with ADHD has not been described yet.
  
  
  METHODS
  The retinal background noise was assessed based on pattern electroretinogram (PERG) data in 20 unmedicated ADHD patients and 20 healthy controls. The PERG is an electrophysiological measure for retinal ganglion cell function. ADHD severity was assessed by interview and questionnaire.
  
  
  RESULTS
  Noise amplitude was significantly higher (138%) in patients with ADHD compared to the control group (p = 0.0047). Noise amplitude correlated significantly with psychometric measures for ADHD (CAARS) especially inattention (r = 0.44, p = 0.004).
  
  
  CONCLUSIONS
  The data provide evidence that an elevated background noise is associated with symptoms of inattention in ADHD and support the use of therapeutic interventions that reduce noise and distraction in patients with ADHD.
authors.affiliation: Department of Psychiatry and Psychotherapy, Albert-Ludwigs-University of Freiburg, Hauptstrasse 5, Freiburg, Germany.
authors.forename: Emanuel
authors.initials: E
authors.lastname: Bubl
authors.affiliation: Department of Psychiatry and Psychotherapy, Albert-Ludwigs-University of Freiburg, Hauptstrasse 5, Freiburg, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Dörr
authors.affiliation: Department of Psychiatry and Psychotherapy, Albert-Ludwigs-University of Freiburg, Hauptstrasse 5, Freiburg, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Riedel
authors.affiliation: Department of Psychiatry and Psychotherapy, Albert-Ludwigs-University of Freiburg, Hauptstrasse 5, Freiburg, Germany.
authors.forename: Dieter
authors.initials: D
authors.lastname: Ebert
authors.affiliation: Department of Psychiatry and Psychotherapy, Albert-Ludwigs-University of Freiburg, Hauptstrasse 5, Freiburg, Germany.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Philipsen
authors.affiliation: University Eye Hospital, Albert-Ludwigs-University of Freiburg, Killianstrasse 5, Freiburg, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Bach
authors.affiliation: Department of Psychiatry and Psychotherapy, Albert-Ludwigs-University of Freiburg, Hauptstrasse 5, Freiburg, Germany.
authors.forename: Ludger
authors.initials: L
authors.lastname: Tebartz van Elst
mesh_terms: D000328:Adult; D001288:Attention / Q000502:physiology*; D001289:Attention Deficit Disorder with Hyperactivity / Q000503:physiopathology* / Q000523:psychology; D016022:Case-Control Studies; D004596:Electroretinography / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009622:Noise / Q000009:adverse effects*; D011594:Psychometrics; D011795:Surveys and Questionnaires; D055815:Young Adult