title: The Speed of Visual Attention and Motor-Response Decisions in Adult Attention-Deficit/Hyperactivity Disorder.
abstract: BACKGROUND
  Adults with attention-deficit/hyperactivity disorder (ADHD) exhibit slowed reaction times (RTs) in various attention tasks. The exact origins of this slowing, however, have not been established. Potential candidates are early sensory processes mediating the deployment of focal attention, stimulus response translation processes deciding upon the appropriate motor response, and motor processes generating the response.
  
  
  METHODS
  We combined mental chronometry (RT) measures of adult ADHD (n = 15) and healthy control (n = 15) participants with their lateralized event-related potentials during the performance of a visual search task to differentiate potential sources of slowing at separable levels of processing: the posterior contralateral negativity (PCN) was used to index focal-attentional selection times, while the lateralized readiness potentials synchronized to stimulus and response events were used to index the times taken for response selection and production, respectively. To assess the clinical relevance of event-related potentials, a correlation analysis between neural measures and subjective current and retrospective ADHD symptom ratings was performed.
  
  
  RESULTS
  ADHD patients exhibited slower RTs than control participants, which were accompanied by prolonged PCN and lateralized readiness potentials synchronized to stimulus, but not lateralized readiness potentials synchronized to response events, latencies. Moreover, the PCN timing was positively correlated with ADHD symptom ratings.
  
  
  CONCLUSIONS
  The behavioral RT slowing of adult ADHD patients was based on a summation of internal processing delays arising at perceptual and response selection stages; motor response production, by contrast, was not impaired. The correlation between PCN times and ADHD symptom ratings suggests that this brain signal may serve as a potential candidate for a neurocognitive endophenotype of ADHD.
authors.affiliation: Department of Psychology, Ludwig-Maximilians-Universität-München, Germany.; Department of Sport-and-Health-Science, Technische Universität München, Munich, Germany.
authors.forename: Fernando
authors.initials: F
authors.lastname: Cross-Villasana
authors.affiliation: Department of Psychology, Ludwig-Maximilians-Universität-München, Germany.; Center for Visual Cognition, Department of Psychology, Københavns Universitet, København, Denmark.. Electronic address: kathrin.finke@psy.lmu/de.
authors.forename: Kathrin
authors.initials: K
authors.lastname: Finke
authors.affiliation: Department of Psychiatry, Ludwig-Maximilians-Universität München, Munich, Germany.; Faculty of Psychology, Universität Wien, Vienna, Austria.
authors.forename: Kristina
authors.initials: K
authors.lastname: Hennig-Fast
authors.affiliation: Department of Psychology, Ludwig-Maximilians-Universität-München, Germany.; Department of Psychiatry, Ludwig-Maximilians-Universität München, Munich, Germany.
authors.forename: Beate
authors.initials: B
authors.lastname: Kilian
authors.affiliation: Department of Psychology, Ludwig-Maximilians-Universität-München, Germany.; Center for Visual Cognition, Department of Psychology, Københavns Universitet, København, Denmark.
authors.forename: Iris
authors.initials: I
authors.lastname: Wiegand
authors.affiliation: Department of Psychology, Ludwig-Maximilians-Universität-München, Germany.; Department of Psychiatry, Ludwig-Maximilians-Universität München, Munich, Germany.
authors.forename: Hermann Joseph
authors.initials: HJ
authors.lastname: Müller
authors.affiliation: School of Psychological Sciences, Birkbeck College, University of London, London, United Kingdom.
authors.forename: Hans-Jürgen
authors.initials: HJ
authors.lastname: Möller
authors.affiliation: Department of Psychology, Ludwig-Maximilians-Universität-München, Germany.; Graduate School of Systemic Neurosciences, Ludwig-Maximilians-Universität-München, Munich, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Töllner
mesh_terms: D000293:Adolescent; D000328:Adult; D001288:Attention / Q000502:physiology*; D001289:Attention Deficit Disorder with Hyperactivity / Q000503:physiopathology* / Q000523:psychology*; D001921:Brain / Q000503:physiopathology*; D003657:Decision Making / Q000502:physiology*; D005071:Evoked Potentials; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008297:Male; D008875:Middle Aged; D011597:Psychomotor Performance / Q000502:physiology*; D011930:Reaction Time; D014796:Visual Perception / Q000502:physiology; D055815:Young Adult
keywords: ADHD; Decision-making; Electroencephalography; Neuro-cognitive endophenotypes; Psychophysics; Stimulus-response translation