How do alcohol and drugs increase the risk of motorcycle crashes?

Alcohol and drugs negatively impact mental and physical skills needed for riding, which significantly increases the risk of motorcycle crashes. When a rider consumes alcohol or uses drugs, it can impair cognitive functions, such as decision-making, attention, and judgment. This impairment can result in slower reaction times and reduced coordination, which are critical for safe motorcycle operation, especially in complex riding environments.

For instance, impaired judgment might lead a rider to take unnecessary risks, such as leaning too far into a turn or misjudging the distance to other vehicles. Similarly, their coordination might be compromised, affecting their ability to control the throttle and brakes effectively. This combination of cognitive and physical impairments contributes to a higher likelihood of accidents.

In contrast, the other options suggest improvements in skills or abilities that are contrary to the effects of alcohol and drugs. These substances do not enhance coordination, reaction time, vision, or judgment; instead, they degrade these essential skills, making riding significantly more dangerous.