Cognitive load while driving impairs memory of moving but not stationary elements within the environment

• We examined knowledge of moving and stationary elements in a driving environment under cognitive load.
• Driving under load conditions led to impaired knowledge of moving, but not stationary, elements.
• Results suggest that not all types of knowledge are equally impaired by a cognitive load while driving.

The negative impact of cognitive load, such as cell phone conversations, while driving is well established, but understanding the nature of this performance deficit is still being developed. To test the impact of load on awareness of different elements in a driving scene, memory for items within the environment was examined under load and no load conditions. Participants drove through two different scenarios in a driving simulator, were periodically interrupted by a pause in the driving during, and were asked questions regarding moving and stationary objects in the environment. Participants in the load condition drove while concurrently counting backwards by sevens. Results indicate that driving under load conditions led to diminished knowledge of moving, but not stationary, objects in the scene. This result suggests not all types of knowledge are equally impaired. Potential implications for current theories of cell phone use while driving and applied attention theory are discussed.