Addiction

• What is substance related addiction

  Characterised by an inability to stop ingesting an external substance into your body that it harmful to health
• What is behavioural addiction

  Inability to stop conducting an action that is harmful to health
• What is physical dependence

  Characterised by withdrawal symptoms when an individual abstains from the substance (shaking, vomiting, sweating)
• What is psychological dependence

  a person feels they must take a substance to feel pleasure or remove feelings of discomfort, they will continue using the substance even if it is harmful until it becomes habituated
• What is tolerance

  • Individuals who repeatedly expose themselves to a substance need higher doses of it to produce the same effects
  • behavioural tolerance is where a person adjusts their behaviour to cope with the effects of a substance, they generally will need to increase the doses they take
• What is cross tolerance

  Tolerance for one substance increases the tolerance for another substance (excessive alcohol consumption can increase tolerance to benzodiazepines)
• What is withdrawal syndrome

  • A collection of symptoms occurring in an individual attempting to stop use of an addictive substance
  • a sign of physical dependence
  • often have the opposite of the rewarding effects of the substance
• What is acute withdrawal phase

  • Happens within hours of stopping use
  • Subside after a number of days
  • Symptoms include pain, nausea, sweating, anger, delirium
• What is prolonged withdrawal phase

  • Continues for weeks, months or years
  • sufferers aer sensitive to cues relating to the substance
  • symptoms include anxiety, sleep difficulties, difficulty concentrating, general fatigue
• Supporting evidence for tolerance, dependence, and withdrawal

  • grabus et al found that it was possible for mice to become dependent on nicotine
  • they showed withdrawal symptoms such as tremors
  • over time the mice required higher levels of nicotine to induce similar responses
• Issues with Grabus study

  • unethical
  • cannot be extrapolated to humans
• Validity issues with researching tolerance and withdrawal

  • level of control in studies is poor
  • data is unreliable as it uses self report methods
  • many extraneous variables such as usage patterns of addicts
  • addicts often lie or are in denial which makes self reporting innacurate
• what is dopamine

  • neurotransmitter that results in feelings of wellbeing and euphoria
  • primary driver of the brains reward system, spikes when we experience something pleasurable
• what is DRD2

  • a candidate gene that provides a predisposition to developing an addiction
  • linked to addiction to nicotine, alcohol, and cocaine
  • low levels of D2 receptors in the brain mean fewer dopamine molecules can bind to these receptors
  • explains why addicts require more of the addictive substance to feel effects of dopamine
• what is CYP2A6

  • candidate gene that reduces the likelihood of developing addiction
  • Pianezza found abnormal gene expression of the gene coding for the CYP2A6 enzyme in non addicts
  • lower levels of this enzyme lead to slower rates of nicotine breakdown reducing the concentration of nicotine metabolites in the brain’s synapses
• Kendler and Prescott Twin study

  • conducted a study on 2000 twins to investigate link between genetic concordance and cocaine use, abuse, and dependency
  • findings indicated that MZ twins are more likely to abuse or be dependent on cocaine that DZ twins
  • since there is not a 100% concordance rate, genetics are shown as providing a vulnerability to addiction rather than a certain reason
• What are the concordance rates found in kendler and prescott study

  • cocaine use: 54% MZ, 42% DZ
  • cocaine abuse: 47% MZ, 8% DZ
  • cocaine dependency: 35% MZ, 0% DZ
• what are the gender differences in genetic vulnerability to addiction?

  • studies on male participants have consistently supported the role played by genetics, whereas results for women are more inconsistent
  • McGue found that only a few adoption studies have reported a significant correlation between female adoptees and their biological parents for addiction
  • this is the same for twin studies which show lower concordance for women than men
  • genetic factors may be less important for women than men
• what are methodological issues with using twins as participants?

  • MZ twins are more likely to be treated similarly by their parents and peers than DZ twins
  • this means that concordance rates could be strongly influenced by upbringing rather than genetic similarity
• how can stress cause addiction?

  • substances can be used to give temporary relief from stress as a coping mechanism
  • this can lead to addiction
• how is stress and addiction a cyclic process?

  • stress can cause addiction, however addiction can cause high levels of stress due to financial and health implications
• what was Wan Sen Yan’s study?

  • aimed to examine whether there was a relationship between stress, personality traits and family functioning in the development of internet addiction in college students
  • 892 students participated
  • several psychometric tests were used to investigate correlations between addiction and stress
• what did Wan Sen Yan find?

  • 10% of students had a severe internet addiction
  • 12% had a mild addiction
  • the severely addicted group had significantly higher levels of stress than any of the other participants
  • the mildly addicted group had higher levels of stress than non addicts
  • concluded there is a relationship between stress, family functioning, personality type, and addiction
• what are limitations of Wan Sen Yan’s research?

  • causal relationship cannot be established
  • 16% of participants did not complete their data sets, potentially affecting the validity of the data results obtained
  • this could affect the results as internet addicted individuals would be less likely to fill out their questionnaires due to the nature of their addiction
• how is causality a limitation of stress as a risk factor?

  • research is only correlational
  • high stress levels may be linked to the likelihood of becoming addicted, but stress could come as a result of the addiction
• how is using animal research a limitation of stress as a risk factor?

  • issues with extrapolation
  • stress can only be inferred in animals, so causes validity issues in results
• what are the practical applications for stress as a risk factor?

  • using stress scales as vulnerability measures in people with addiction issues
  • these can be used to identify triggers for addictive behaviours as well as being a predictor for relapse
  • a strong correlation between relapse and high stress levels has been established
• why is there a higher rate of addiction in cities?

  • there are higher levels of stress in cities or areas with dense population levels
  • a link has been found between the overcrowding of urban areas and higher levels of addiction
  • however all evidence supporting this claim is correlational and there are a number of extraneous factors affecting these statistics (e.g. drugs being more readily available)
• what is a pathological personality?

  • people are predominantly negative and find life more difficult than most
  • they are more likely to be addicts as the temporary high gained from a substance or behaviour would reduce feelings of pathology
• what is eysenck‘s addictive personality concept?

  • suggests personality is biologically determined
  • all people exhibit traits including psychoticism, extroversion, and neuroticism
  • people with addictive personalities have higher psychoticism and neuroticism, and lower extroversion
• how does Wan Sen Yan’s study support Eysenck?

  • the severely addicted participants showed high neuroticism and lower extroversion compared to mild/non addicts
• what is cloninger’s tridimensional theory?

  • suggests that there are three key traits that make an individual liable to substance abuse
  • novelty seeking: the need for change and stimulation
  • reward dependence: individuals learn from and react to rewarding situations quickly and easily
  • harm avoidance: the amount a person worries about the negative elements of a situation
• what is supporting evidence for cloninger’s theory?

  • Zuckerman found a clear link between novelty seeking and a concept he termed ‘sensation seeking personality’ whereby addicts were likely to exhibit novelty seeking behaviour for the physical effects of drugs
  • Howard et al conducted a meta analysis and found that novelty seeking was a strong predictor of alcohol abuse in teenagers and young adults, however the link between addiction and reward dependence was less clear
• how is individual differences a limitation of personality?

  • the possession of characteristics such as extroversion or novelty seeking does not automatically mean that an addiction will occur
  • others factors such as genetics, family, or stress can influence development of addiction
• why is cause and effect a limitation of personality?

  • research only indicates the likelihood of developing an addiction, rather than being the sole cause or mechanism through which addictions begin
  • this means that the personality explanation is incomplete and is likely to be involved as a part of an interactionist explanation
• why is contradictory research a limitation of personality?

  • Eysenck’s theory argues that addicts show lower levels of extraversion, however cloningers theory maintains that addicts are likely to show high levels of novelty seeking, which suggests extraversion should be high in addicts
  • this reduces the validity of personality as a risk factor
• what is the common rewards pathway?

  • nicotine is consumed - nicotine receptors in the ventral tegmental region are activated
  • the ventral tegmental area is stimulated - this area has a high density of dopamine neurons which elicits a sense of reward
  • nucleus accumbens is triggered - this is part of the limbic system associated with reward networks, strengthening the link between nicotine and a sense of reward
  • activity in the prefrontal cortex is boosted - stimulates a strong positive emotional response to dopamine
• why do nicotine addicts continually have to smoke cigarettes?

  • as the common rewards pathway is stimulated, dopamine levels increase and serotonin levels decrease
  • dopamine is released every time the addictive substance is used, whereas serotonin levels are decreased, causing a lack of satiety or contentedness
  • the more dopamine an action elicits, the more likely a person is to repeat it
• what is the opioid system?

  • regulates affective processing including pain, pleasure, and reward
  • smoking stimulates the brains opioid system by activating enkephalins and endorphins
  • these are chemicals associated with pleasure and pain reduction , which is why smokers perceive nicotine use as pleasurable
• what is neuroadaptation?

  • the brains neurons are affected by external influences
  • in persistent smokers, the neural networks adapt to produce less dopamine over time and this in turn leads to smokers increasing their nicotine consumption in an attempt to restore high levels of dopamine and pleasure
  • the areas of the brain responsible for decision making and control are negatively affected, potentially causing the increase in repetitive behaviour