Dutch researchers had 10 volunteers spend an hour inhaling either clean air or diesel exhaust fumes. They found that those inhaling exhaust fumes showed stress responses and changes to brain cortex activity on EEGs within 30 minutes, indicating alterations to how their brains processed information, and these effects persisted after exposure. The study suggests long-term exposure to traffic nanoparticles from exhaust could interfere with normal brain function and information processing.