The nature of physical and psychological dependence in addiction

Addiction to substances like nicotine in cigarettes can manifest in two distinct forms: physical and psychological dependence. These types of dependence explain why individuals find it challenging to stop smoking despite known health risks.

Types of dependence in smoking addiction

• Physical dependence - This occurs when the body adapts to the presence of nicotine and requires it to function normally. Without the substance, the body experiences discomfort, driving the need to smoke to restore a sense of normalcy.
• Psychological dependence - This is a mental reliance on smoking, where individuals believe they need cigarettes to cope with stress, anxiety, or social situations. The perceived necessity of smoking to maintain emotional balance perpetuates the habit.

The role of tolerance and withdrawal symptoms in smoking addiction

Addiction to smoking is reinforced by the development of tolerance and the experience of withdrawal symptoms. These physiological and psychological responses make quitting a significant challenge for many smokers.

Understanding tolerance in smoking

• Adaptation to nicotine - Over time, the body becomes accustomed to nicotine, meaning the initial amount smoked no longer produces the same pleasurable effects.
• Increased consumption - To achieve the desired feelings of relaxation or satisfaction, smokers must consume larger quantities of nicotine, often leading to more frequent smoking.

Experiencing withdrawal symptoms

• Discomfort upon cessation - When a smoker reduces or stops nicotine intake, the body reacts with unpleasant symptoms such as irritability, anxiety, and cravings.
• Relief through smoking - These symptoms can be alleviated by smoking again, which reinforces the addictive cycle as the smoker seeks to avoid discomfort.

Brain neurochemistry as an explanation for smoking addiction

The addictive nature of smoking can be understood through the impact of nicotine on brain neurochemistry, particularly its effect on the neurotransmitter dopamine. This biochemical process underlies the rewarding sensations that keep smokers returning to cigarettes.

How nicotine affects the brain

• Dopamine release - Nicotine triggers the release of dopamine in the brain, activating receptors on neurons and creating feelings of pleasure and relaxation.
• Diminishing effects - After dopamine is cleared from the synapses through reuptake, the pleasurable feelings fade, prompting a desire to smoke again to recapture the sensation.
• Body adaptation - With regular nicotine use, the brain reduces its natural dopamine production, relying on cigarettes to maintain normal levels, which reinforces smoking behaviour.
• Challenges of quitting - Stopping smoking leads to a dopamine deficit, causing withdrawal symptoms like anxiety and nausea until the brain readjusts to functioning without nicotine.

Research on dopamine and addiction: Olds and Milner (1954)

• Method - Rats were fitted with an electrode in the hypothalamus of their brain. Pressing a lever activated the electrode, stimulating dopamine release.
• Results - Rats repeatedly pressed the lever to experience dopamine release, even choosing to cross a painful electric grid to reach it.
• Conclusions - The persistent lever-pressing, despite discomfort, suggests that dopamine release is highly rewarding and can drive addictive behaviour.
• Evaluation - As a controlled laboratory study, it offers insight into dopamine's role in addiction, but results from rats may not fully apply to humans. Ethical concerns also arise from the use of animals in such experiments.

Additional supporting evidence

• Zhang et al (2012) - Research on mice exposed to nicotine for several weeks showed that sudden cessation led to abnormally low dopamine levels, supporting the idea that nicotine dependency alters brain chemistry.

Learning theory as an explanation for smoking addiction

Learning theory provides a psychological perspective on smoking addiction, suggesting that the behaviour is acquired through observation, reinforcement, and environmental associations. This approach highlights the social and situational factors that contribute to starting and maintaining smoking habits.

Key concepts of learning theory in smoking

• Observation and modelling - Individuals may start smoking by imitating role models such as parents, peers, or celebrities, especially if they perceive positive consequences like social acceptance.
• Operant conditioning - Smoking can be reinforced positively through benefits like fitting in with a group, or negatively by relieving withdrawal symptoms or avoiding stress and boredom.
• Cue reactivity and classical conditioning - Smoking often becomes linked with specific environments or objects (e.g., coffee, alcohol, or other smokers). These cues trigger cravings as the body anticipates nicotine, making it hard to resist smoking in those contexts.

Research on social learning: Akers and Lee (1996)

• Method - A five-year longitudinal study involved 512 secondary school students completing self-report questionnaires. These assessed smoking frequency and social learning factors, such as friends' smoking habits and perceived attitudes of friends and family towards smoking.
• Results - Strong positive correlations were found between social learning factors and the likelihood of smoking.
• Conclusions - Social learning plays a significant role in the initiation of smoking during adolescence.
• Evaluation - Self-report methods may lack reliability, and correlation does not confirm causation. The study also did not differentiate the impact of variables like gender or the relative influence of peers versus parents.

Additional supporting evidence

• Moolchan et al (2000) - Found that 68% of teenage smokers had at least one smoking parent and felt smoking helped them socially integrate with peers, supporting social learning and operant conditioning theories.
• Engelmann et al (2012) - A meta-analysis of fMRI studies showed that smoking-related cues triggered stronger neural responses in smokers compared to neutral cues, reinforcing the concept of cue reactivity.

Strengths and weaknesses of explanations for smoking addiction

Both brain neurochemistry and learning theory offer valuable insights into smoking addiction, but each has its own advantages and limitations.

Evaluating brain neurochemistry explanation

• Strengths:
  • Research like Olds and Milner (1954) and Zhang et al (2012) supports the role of dopamine in addiction, providing a scientific basis for understanding nicotine dependence.
  • Laboratory studies allow tight control over variables, increasing the likelihood of establishing cause and effect by minimising external influences.
• Weaknesses:
  • Focusing solely on neurotransmitters is reductionist, overlooking psychological aspects of addiction.
  • It neglects genetic factors, as studies like Dowsett (2002) suggest inherited tendencies may play a role in addiction, evidenced by higher rates of alcoholism among children of alcoholics despite non-alcoholic adoptive environments.
  • Generalising findings from animal studies to humans poses challenges due to biological and behavioural differences.

Evaluating learning theory explanation

• Strengths:
  • Studies often involve human participants, avoiding the generalisation issues associated with animal research.
  • This approach explains both physical and psychological addictions, applicable even to substances with minimal physical withdrawal effects.
• Weaknesses:
  • It adopts a nomothetic perspective, assuming uniform addiction processes and ignoring individual differences or other factors like biology and genetics.
  • It overlooks the role of free will, failing to account for personal choice in deciding to smoke despite awareness of health risks.