Strobe lights have been used successfully in many transportation applications to increase conspicuity. It was hoped that a strobe signal could also be applied to more effectively warn distracted drivers of an unexpected rear end conflict.

This "proof of concept study" used a 2 x 2 between-subjects design using thirty-three subjects (16 subjects in the strobe condition, 17 subjects in the no strobe condition) who were divided into two age groups: younger (25-35) and older (60-70). The driver unexpectedly encountered a stopped "surrogate" vehicle in the roadway (with or without a rear-facing strobe light) in a controlled on-road study at the Smart Road located at the Virginia Tech Transportation Institute (VTTI).

Results suggested that younger subjects' perception times improved as a result of being exposed to the strobe signal. Faster perception of the situation allowed more time to initiate a brake response. Older subjects perception and response times remained unchanged by the strobe signal. More severe initial steering rate and subjective responses indicated that the strobe conveyed a sense of urgency irrespective of age.

Visual distraction of subjects proved difficult. Hence, the impact of the strobe on attracting the attention of a visually distracted driver to the stimulus could not be as fully investigated as originally hoped. The formulation of a more difficult distraction task was suggested for future research to truly assess the ability of the strobe light at alerting visually distracted drivers.