title: Seeing pedestrians at night: effect of driver age and visual abilities.
abstract: OBJECTIVE
  To quantify the effects of driver age on night-time pedestrian conspicuity, and to determine whether individual differences in visual performance can predict drivers' ability to recognise pedestrians at night.
  
  
  METHODS
  Participants were 32 visually normal drivers (20 younger: M = 24.4 years ± 6.4 years; 12 older: M = 72.0 years ± 5.0 years). Visual performance was measured in a laboratory-based testing session including visual acuity, contrast sensitivity, motion sensitivity and the useful field of view. Night-time pedestrian recognition distances were recorded while participants drove an instrumented vehicle along a closed road course at night; to increase the workload of drivers, auditory and visual distracter tasks were presented for some of the laps. Pedestrians walked in place, sideways to the oncoming vehicles, and wore either a standard high visibility reflective vest or reflective tape positioned on the movable joints (biological motion).
  
  
  RESULTS
  Driver age and pedestrian clothing significantly (p < 0.05) affected the distance at which the drivers first responded to the pedestrians. Older drivers recognised pedestrians at approximately half the distance of the younger drivers and pedestrians were recognised more often and at longer distances when they wore a biological motion reflective clothing configuration than when they wore a reflective vest. Motion sensitivity was an independent predictor of pedestrian recognition distance, even when controlling for driver age.
  
  
  CONCLUSIONS
  The night-time pedestrian recognition capacity of older drivers was significantly worse than that of younger drivers. The distance at which drivers first recognised pedestrians at night was best predicted by a test of motion sensitivity.
authors.affiliation: School of Optometry and Vision Science, Queensland University of Technology, Brisbane, Australia.
authors.forename: Joanne M
authors.initials: JM
authors.lastname: Wood
authors.forename: Philippe
authors.initials: P
authors.lastname: Lacherez
authors.forename: Richard A
authors.initials: RA
authors.lastname: Tyrrell
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001334:Automobile Driving; D015350:Contrast Sensitivity / Q000502:physiology; D003624:Darkness; D005260:Female; D005556:Form Perception / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009039:Motion Perception / Q000502:physiology; D055254:Night Vision / Q000502:physiology*; D011481:Protective Clothing; D011930:Reaction Time; D014792:Visual Acuity / Q000502:physiology; D014794:Visual Fields / Q000502:physiology; D055815:Young Adult
keywords: age; motion sensitivity; night-time driving; pedestrian recognition