Questão 22

Although the extremes are different, there is considerable overlap. A habit is an action repeated so often that it becomes automatic, such as cleaning your teeth or making tea. The brain learns to treat the series of movements as one chunk and can complete them without further thought. Habits are rarely harmful and can be controlled or changed. An addiction, by contrast, controls you. Drugs, watching porn and other activities can all become addictive when the addict loses control of his cravings, often with terrible consequences. Many addictive drugs show increased tolerance, which means more is needed each time. This can be combined with withdrawal symptoms such as ‘cold turkey’ from heroin or ‘delirium tremens’ from alcohol, but this is not always the case. First time cannabis users often report no effect, and withdrawal symptoms are usually mild. Between the extremes are habits that are hard to break or mild addictions that do little harm.

Alex Round, Science World , December 2014

Which of the following statements is TRUE, according to TEXT A?