Addiction in general has been described as a compulsive craving for something in spite of negative consequences that come from pursuing its use. The compulsive cravings of addiction have physiological, psychological, and emotional components. Traditionally, the notion of addictions has been connected with cocaine, alcohol, heroin, nicotine, and other chemically based substances. Current thinking is that there are certain compulsive behaviors — including gambling, shopping, eating, and watching pornography — that can set off similar addictive responses in the brain.