Describing Addiction: Physical & Psychological Dependence

Addiction is a complex, chronic, relapsing condition that involves compulsive engagement in a behaviour or substance use despite harmful consequences. Understanding the distinction between physical dependence and psychological dependence, the diagnostic criteria for addiction, and the key risk factors is essential for the AQA A-Level Psychology addiction topic. Throughout this lesson, we use smoking, alcohol, and gambling as the primary examples, as specified by the AQA syllabus.

Key Definition: Addiction is a chronic, relapsing disorder characterised by compulsive drug-seeking or behaviour, continued use despite harmful consequences, and long-lasting changes in the brain. It is regarded as a brain disorder involving changes to reward, motivation, and memory circuits.

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Physical Dependence vs Psychological Dependence

Feature	Physical Dependence	Psychological Dependence
Definition	The body has adapted to the presence of a substance, so that withdrawal produces physical symptoms	A perceived need for a substance or behaviour to function normally or to cope emotionally
Key features	Tolerance, withdrawal symptoms	Craving, compulsive use, preoccupation
Tolerance	Needing increasing amounts of a substance to achieve the same effect	May develop (e.g., needing to gamble with increasing amounts) but less clearly defined
Withdrawal	Physical symptoms when the substance is removed (e.g., tremors, sweating, nausea, seizures for alcohol; irritability, headaches for nicotine)	Psychological symptoms when the behaviour is stopped (e.g., anxiety, restlessness, irritability, depression)
Examples	Alcohol, heroin, nicotine, benzodiazepines	Gambling, gaming, cannabis (primarily psychological), cocaine (primarily psychological)

Key Definition: Tolerance is a physiological adaptation in which the body requires increasing doses of a substance to achieve the same effect that was originally produced by a lower dose. Withdrawal refers to the unpleasant physical and psychological symptoms that occur when a substance is reduced or stopped after prolonged use.

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DSM-5 Diagnostic Criteria

The DSM-5 (APA, 2013) replaced the previous distinction between "substance abuse" and "substance dependence" with a single diagnosis: Substance Use Disorder (SUD). The severity is assessed on a spectrum:

• Mild: 2–3 criteria met
• Moderate: 4–5 criteria met
• Severe: 6 or more criteria met

The 11 DSM-5 Criteria for Substance Use Disorder

1. Taking the substance in larger amounts or for longer than intended
2. Wanting to cut down or stop but being unable to
3. Spending a great deal of time obtaining, using, or recovering from the substance
4. Cravings and urges to use the substance
5. Failure to fulfil major role obligations (work, school, home)
6. Continued use despite social or interpersonal problems caused by the substance
7. Giving up important social, occupational, or recreational activities
8. Recurrent use in physically hazardous situations
9. Continued use despite knowing it causes physical or psychological problems
10. Tolerance (needing more to achieve the same effect)
11. Withdrawal symptoms when the substance is reduced or stopped

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Behavioural Addictions

Gambling Disorder

Gambling disorder is the only behavioural addiction formally recognised in the DSM-5. It was reclassified from "Impulse Control Disorders" to "Substance-Related and Addictive Disorders" in the 2013 revision, reflecting evidence that gambling shares neurobiological features with substance addictions (particularly involvement of the dopamine reward system).

Gaming Disorder (ICD-11)