Psychological Research on Information, Signage, and Maneuvers in Drivers (PRISM)

Current sign-placement guidance identifies where a sign is applicable, but it does not empirically account for what drivers are attending to immediately after a maneuver. After a turn or merge, drivers must stabilize steering, adjust speed, monitor surrounding traffic, and reorient to the forward roadway. During this interval, visual and cognitive resources are constrained. If a speed limit sign or other regulatory sign is encountered before attentional recovery, the sign may fall outside active search behavior, reducing the likelihood of fixation, processing, memory encoding, and subsequent compliance. The PRISM project addresses this gap by measuring post-maneuver attentional recovery and fixation timing, then converting those timing distributions into distance-based placement guidance. Existing placement distances are largely based on convention or engineering judgment rather than observed human performance. The proposed work creates a performance-based framework that links time-to-first-fixation, recognition outcomes, and roadway distance so that sign placement can better match driver information-processing capacity. This is particularly important in high-workload locations such as merges, intersections, transition zones, and work-zone approaches, where drivers may be least able to detect and encode new regulatory information. The study also has a broader human-factors and safety rationale. Attentional recovery and fixation timing can vary by age, experience, and task demands. Without percentile-based placement recommendations, current practices may under-serve older drivers, less experienced drivers, and drivers navigating unfamiliar environments. The resulting framework is intended to support safer and more consistent speed transitions and to provide the Utah Department of Transportation (UDOT) with defensible, data-driven placement guidance for speed-limit and related signs. Finally, the results of this work have direct implications for the development of direct guidelines and policies that are guiding the placement of traffic signs to increase safety and compliance. The decision support tool provided based on the results of this project will allow UDOT engineers to identify the optimal location of traffic sign placement with direct translation of the research into implementation efforts.

Language

• English

Project

• Status: Active
• Funding: $74,900.00
• Contract Numbers:

  278346

  UT26.3H

• Sponsor Organizations:

  Utah Department of Transportation

  Research and Innovation Division
  Salt Lake City, UT  United States  84114
• Managing Organizations:

  Utah Department of Transportation

  Research and Innovation Division
  Salt Lake City, UT  United States  84114
• Project Managers:

  Jensen, Travis

• Performing Organizations:

  University of Utah, Department of Psychology

  380 S 1530 E RM 502
  Salt Lake City, Utah  United States  84112
• Start Date: 20260908
• Expected Completion Date: 20271130
• Actual Completion Date: 0
• USDOT Program: Behavioral Safety Research
• Subprogram: Highway Safety
• Subprogram: Human_Factors

Subject/Index Terms

• TRT Terms: Drivers; Driving behavior; Human factors; Location; Traffic signs
• Identifier Terms: PRISM
• Geographic Terms: Utah
• Subject Areas: Highways; Operations and Traffic Management; Safety and Human Factors;

Filing Info

• Accession Number: 02001930
• Record Type: Research project
• Source Agency: Utah Department of Transportation
• Contract Numbers: 278346, UT26.3H
• Files: RIP, STATEDOT
• Created Date: Sep 10 2026 1:33PM