The Role of Visibility, Attention & Memory in Accidents

Human capabilities, limitations, and behaviors contribute significantly to accident causation and the reporting of evidence surrounding accidents. Cognitive, perceptual, and performance characteristics of humans lead to analyzable trends and patterns of behaviors that can either increase or decrease the safety of any interaction between a human and a product, environment, or system. Exponent’s human factors scientists and engineers are uniquely qualified to analyze the behavioral traits and capabilities of humans in a variety of roles (e.g., operators, pedestrians, drivers, eyewitnesses) and to provide a scientific foundation on which to base our understanding of human cognition, perception, and behavior.

Exponent scientists investigate human performance issues relating to visual and auditory perception, reaction time, eyewitness memory, hindsight bias, attention, distraction, and fatigue. Furthermore, physical aspects of the environment (e.g., lighting, background noise, and weather) and characteristics of the operator (e.g., age, strength, experience, size) are integral human factors considerations in accident investigations. Our scientists analyze a given accident and evaluate the human performance issues and behaviors that may have contributed to accident causation. Exponent scientists can further address the reliability of human memory and retrospective reporting in the gathering of fact-based evidence.


Our services include:

  • Assess human performance as a contributor to accident causation 
  • Analyze the visibility and available lines of sight in a visual environment
  • Create perceptually accurate reproductions of low-illumination scenes 
  • Evaluate the likely effectiveness of additional or alternative safety-related information, guarding, or design interventions in accident avoidance 
  • Determine the role of attention and distraction on human behavior and safety-related actions 
  • Characterize human memory, information processing, and the potential for inaccuracies in eyewitness testimony 
  • Evaluate hindsight bias—the biasing effect that knowledge of an outcome has on the perception and interpretation of prior events 
  • Consider potential for accident avoidance given human perception-reaction times 
  • Assess the effects of age, drugs and/or alcohol, and existing medical conditions on human performance