Which of the following best describes tolerance?

Tolerance is understood as a physiological process that occurs when the body is repeatedly exposed to a substance, resulting in a diminished response to its effects over time. This means that higher doses of the substance are required to achieve the same effects that were initially experienced at lower doses. This phenomenon can be observed with various substances, including medications, alcohol, and illicit drugs, where the individual may find that their reaction to the substance decreases as they continue to use it.

In contrast, heightened sensitivity, withdrawal symptoms, and cravings are related but distinct concepts. Increased sensitivity typically refers to an enhanced response to a substance, which is the opposite of tolerance. Withdrawal describes symptoms that can occur when a substance is discontinued after prolonged use, while psychological adaptation involves mental and emotional responses to substance use, leading to cravings. These processes may coexist with tolerance but are not representative of what tolerance specifically entails.