title: Detecting color vision in a malingerer.
abstract: A patient describing himself as totally color blind was ordered by the judicial system to have his color vision investigated in order to establish his suitability for military service. Basic clinical (Farnsworth Panel D-15, Moreland and Rayleigh anomaloscope equations), electroretinographic (ERG) and psychophysical techniques (spectral sensitivities) were applied to determine the extent of his color discrimination performance and cone function. These standard procedures were complemented by a test for cone interaction (transient tritanopia) and by newly developed cone-isolating flicker large-field ERG recordings. The patient's data consistently indicate the function as well as the functional interaction of the middle-wavelength-sensitive (M-) and the short-wavelength-sensitive (S-) cones. But the function of the long-wavelength-sensitive (L-) cones was completely absent. Hence the patient was correctly demonstrated to be a protanope. This study establishes that standard classical procedures, in combination with newly developed and easy to apply psychophysical and ERG ones, which can be reliably used to assess true color discrimination performance, in difficult cases of malingering.
authors.affiliation: University Eye Hospital, Department of Pathophysiology of Vision & Neuro-Ophthalmology, Schleichstr. 12-16, D-72076 Tübingen, Germany. herbert.jaegle@uni-tuebingen.de
authors.forename: Herbert
authors.initials: H
authors.lastname: Jägle
authors.forename: Bettina
authors.initials: B
authors.lastname: Sadowski
authors.forename: Jan
authors.initials: J
authors.lastname: Kremers
authors.forename: Hendrik P N
authors.initials: HP
authors.lastname: Scholl
authors.forename: Beate
authors.initials: B
authors.lastname: Leo-Kottler
authors.forename: Lindsay T
authors.initials: LT
authors.lastname: Sharpe
mesh_terms: D000328:Adult; D003118:Color Perception / Q000502:physiology*; D003119:Color Perception Tests; D003117:Color Vision Defects / Q000175:diagnosis / Q000503:physiopathology*; D004185:Disability Evaluation; D004596:Electroretinography / Q000379:methods; D006801:Humans; D008297:Male; D008306:Malingering / Q000175:diagnosis / Q000503:physiopathology*; D017949:Retinal Cone Photoreceptor Cells / Q000502:physiology*; D012684:Sensory Thresholds