**Drowsiness** is a state in which a person feels **tired** and **heavy in the body**, which can affect their ability to drive safely. This state not only increases the risk of falling asleep at the wheel but also affects **concentration** in traffic.

- When a person is drowsy, they experience **difficulties in making decisions** and may take longer to react to situations on the road. This means that their attention and ability to concentrate in traffic are compromised.

- Drowsiness can be caused by several factors, such as **sleeping fewer hours than usual**, **changing sleep schedules**, or **driving on roads with little traffic**, which can cause the driver to relax too much and lose concentration.

- Additionally, the consumption of **alcohol or medications** before driving, as well as driving at times of the day when the body naturally feels sleepier, such as **early morning or after eating**, can also increase drowsiness.

Therefore, drowsiness makes it more difficult to maintain concentration in traffic, as it affects the driver's ability to stay alert and make quick and effective decisions.