Brain power decreases by what percent when a driver listens to someone talk (passenger or radio)?

Brain power decreases by what percent when a driver listens to someone talk (passenger or radio)?

• A. 10%
• B. 25%
• C. 40%
• D. 5%

Answer: (C)

When you talk or listen to someone while driving, your brain’s attention is split between the conversation and driving tasks. That division uses cognitive resources that are also needed for scanning the road, noticing hazards, and making quick, accurate decisions. Because of this shared attention, driving performance can drop significantly—about 40%—leaving less mental power to process what’s happening around you. That reduction translates to slower reaction times, incomplete hazard perception, and poorer judgment of speed and distance. So, the best answer reflects the substantial hit to brain power when engaged in a conversation while driving.

When you talk or listen to someone while driving, your brain’s attention is split between the conversation and driving tasks. That division uses cognitive resources that are also needed for scanning the road, noticing hazards, and making quick, accurate decisions. Because of this shared attention, driving performance can drop significantly—about 40%—leaving less mental power to process what’s happening around you. That reduction translates to slower reaction times, incomplete hazard perception, and poorer judgment of speed and distance. So, the best answer reflects the substantial hit to brain power when engaged in a conversation while driving.