Stress and drug abuse: the brain connection.

• Position: Brief article

You are about to take a test. The coach is announcing who made the team. Your best friend is mad at you. Most people find such situations stressful. Stress can be defined as an emotional or physical demand or strain (a "stressor") that causes your body to release powerful neurochemicals and hormones. These changes help your body gear up to respond to the stressor. Your blood-sugar levels and blood pressure rise; your heart beats faster; your muscles tense.

There are different levels of stress: Short-term stress can cause uncomfortable physical reactions, but can also help you to focus. Long-term stress--such as stress caused by...