title: A yellow filter improves response times to low-contrast targets and traffic hazards.
abstract: OBJECTIVE
  Anecdotal evidence suggests that some sunglass users prefer yellow tints for outdoor activities, such as driving, and research has suggested that such tints improve the apparent contrast and brightness of real-world objects. The aim of this study was to establish whether yellow filters resulted in objective improvements in performance for visual tasks relevant to driving.
  
  
  METHODS
  Response times of nine young (age [mean ± SD], 31.4 ± 6.7 years) and nine older (age, [mean ± SD], 74.6 ± 4.8) adults were measured using video presentations of traffic hazards (driving hazard perception task) and a simple low-contrast grating appeared at random peripheral locations on a computer screen. Response times were compared when participants wore a yellow filter (with and without a linear polarizer) versus a neutral density filter (with and without a linear polarizer). All lens combinations were matched to have similar luminance transmittances (~27%).
  
  
  RESULTS
  In the driving hazard perception task, the young but not the older participants responded significantly more rapidly to hazards when wearing a yellow filter than with a luminance-matched neutral density filter (mean difference, 450 milliseconds). In the low-contrast grating task, younger participants also responded more quickly for the yellow filter condition but only when combined with a polarizer. Although response times increased with increasing stimulus eccentricity for the low-contrast grating task, for the younger participants, this slowing of response times with increased eccentricity was reduced in the presence of a yellow filter, indicating that perception of more peripheral objects may be improved by this filter combination.
  
  
  CONCLUSIONS
  Yellow filters improve response times for younger adults for visual tasks relevant to driving.
authors: School of Optometry and Vision Science and Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia. p.lacherez@qut.edu.au
authors: Philippe
authors: P
authors: Lacherez
authors: Alexander K
authors: AK
authors: Saeri
authors: Joanne M
authors: JM
authors: Wood
authors: David A
authors: DA
authors: Atchison
authors: Mark S
authors: MS
authors: Horswill
mesh_terms: D000063:Accidents, Traffic / Q000517:prevention & control* / Q000706:statistics & numerical data; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001334:Automobile Driving / Q000592:standards*; D003118:Color Perception; D015350:Contrast Sensitivity; D005139:Eyeglasses; D005260:Female; D005374:Filtration / Q000295:instrumentation*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010775:Photic Stimulation; D011930:Reaction Time; D014792:Visual Acuity; D055815:Young Adult