Related Experiment Video
Updated: Jul 2, 2026
Measuring the Behavioral Effects of Intraocular Scatter
Published on: February 18, 2021
Effect of task and eccentricity of the target on detection thresholds in mesopic vision: implications for road
Anaïs Mayeur1, Roland Brémond, J M Christian Bastien
1Laboratoire Central des Ponts et Chaussées, Paris, France.
Objective:
The aim of this work is to assess how adding a driving-related task affects the detection of objects in peripheral vision, under mesopic conditions.
Background:
The main index used to assess the quality of road lighting installations refers to simple detection tasks in foveal vision, which raises methodological and practical questions.
Method:
The experimental design consisted of a three-phase experiment. In the first phase, two groups (control and experimental) performed a peripheral detection task (simple task). Based on these results an individual detection threshold was computed for each participant and eccentricity. A tracking task was performed in Phase 2 for both groups (steering a tracking target along a circuit, on a screen). In the third phase, the control group performed the same task as in Phase 2. The experimental group performed a double task, with a tracking (primary) task and a peripheral detection (secondary) task.
Results:
The data show an effect of the tracking task and eccentricity on peripheral event detection. The tracking task caused detection performance to decrease from 84.2% to 67.5%, p < .001.
Conclusion:
The small target visibility model used in road lighting may be improved, taking into account the effects of task and eccentricity on target detection.
Application:
This study supports improved roadway lighting design by guiding consideration of sign eccentricity and task load.
