title: Color vision in attention-deficit/hyperactivity disorder: a pilot visual evoked potential study.
abstract: BACKGROUND
  Individuals with attention-deficit/hyperactivity disorder (ADHD) are reported to manifest visual problems (including ophthalmological and color perception, particularly for blue-yellow stimuli), but findings are inconsistent. Accordingly, this study investigated visual function and color perception in adolescents with ADHD using color Visual Evoked Potentials (cVEP), which provides an objective measure of color perception.
  
  
  METHODS
  Thirty-one adolescents (aged 13-18), 16 with a confirmed diagnosis of ADHD, and 15 healthy peers, matched for age, gender, and IQ participated in the study. All underwent an ophthalmological exam, as well as electrophysiological testing color Visual Evoked Potentials (cVEP), which measured the latency and amplitude of the neural P1 response to chromatic (blue-yellow, red-green) and achromatic stimuli.
  
  
  RESULTS
  No intergroup differences were found in the ophthalmological exam. However, significantly larger P1 amplitude was found for blue and yellow stimuli, but not red/green or achromatic stimuli, in the ADHD group (particularly in the medicated group) compared to controls.
  
  
  CONCLUSIONS
  Larger amplitude in the P1 component for blue-yellow in the ADHD group compared to controls may account for the lack of difference in color perception tasks. We speculate that the larger amplitude for blue-yellow stimuli in early sensory processing (P1) might reflect a compensatory strategy for underlying problems including compromised retinal input of s-cones due to hypo-dopaminergic tone.
authors.affiliation: Department of Applied Psychology & Human Development OISE, University of Toronto, Toronto, Canada.
authors.forename: Soyeon
authors.initials: S
authors.lastname: Kim
authors.affiliation: Department of Child and Adolescent Psychiatry and Psychotherapy Central Institute of Mental Health, Mannheim, Germany; Department of Cognitive and Clinical Neuroscience, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany.
authors.forename: Tobias
authors.initials: T
authors.lastname: Banaschewski
authors.affiliation: Department of Applied Psychology & Human Development OISE, University of Toronto, Toronto, Canada; Neuroscience & Mental Health Research Program, The Hospital for Sick Children, Toronto, Canada. Electronic address: rosemary.tannock@utoronto.ca.
authors.forename: Rosemary
authors.initials: R
authors.lastname: Tannock
mesh_terms: D000293:Adolescent; D000704:Analysis of Variance; D001289:Attention Deficit Disorder with Hyperactivity / Q000503:physiopathology*; D016022:Case-Control Studies; D003118:Color Perception / Q000502:physiology*; D015350:Contrast Sensitivity / Q000502:physiology; D005074:Evoked Potentials, Visual / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D010775:Photic Stimulation; D010865:Pilot Projects; D012029:Refraction, Ocular / Q000502:physiology; D014792:Visual Acuity
keywords: ADHD; Adolescent; Color vision deficit; TDAH; Visual evoked potential; adolescente; déficit de visión del color; potencial evocado visual