Addiction

• health psychology


  an applied discipline of psychology concerned w applying psychological theory to help improve the health of a population
• types of addiction


  - past: seen in relation to a drug [chemical addiction]

  - but it is incr recognised that addictions can also occur within behaviours & definitions have tended to move towards describing reduced lvls of control regarding the behav

  - [i.e. person will indulge in the behav despite attempts not to]

  - e.g. of behav addic: gambling, gaming, sex
• criteria for addiction


  Carnes 1991

  > a behav is out of control > severe consequences

  > inability to stop despite consequences

  > persistent pursuit of self-destruc/risky behav

  > desire to stop behav

  > use of behav as coping strat

  > incr lvls of behav needed to get same effect [tol]

  > lots of time spent both in trying to engage in the behav as well as recovery

  > severe mood changes when carrying out the behav

  > social, occupational & recreational activities sacrificed
• addiction


  a disorder where individs indulge in a substance or behav that is pleasurable bu eventually becomes a compulsion with potentially harmful consequences

  > recently become a condition defined in DSM-V

  > only behav addiction is gambling addiction

  > key features incl depend, tol, withdrawal syn
• physical dependence


  defined in terms of withdrawal

  > i.e. if stopping taking the substance will lead to a withdrawal syndrome
• psychological dependence


  is the compulsion to experience the effects of the substance or behav for a reward [either for pleasure or reducing discomfort]

  - this becomes habitual despite harmful consequences
• tolerance


  describes how an individs response to an amount of drug or behav becomes reduced due to previous exposure

  - typically countered by the addict by incr the dosage or engaging in behav more freq or seeking more extreme e.g. of the behav
• tolerance - behavioural tolerance


  behav tol: addict may learn to adjust their behav in response to the effects of their addiction

  - such as a person addicted to alcohol may walk slower to compensate for the reduced balance & co-ordination
• tolerance - cross-tolerance


  where tolerance to one drug leads to a similar tolerance of another, this can be seen in the need to incr dosages of anaesthetics in ppl w alcoholism
• withdrawal syndrome


  a cluster of symptoms associated w not engaging w drug/behav, oft characterised by being opposite effect to those created by the drug/behav

  - avoidance of withdrawal symptoms can become a motivation for persisting in a behav, creating a secondary form of psychological dependence
• risk factors in the development of addiction


  - internal & external influences that incr the likelihood of developing an addiction

  - these are typic established through looking at the prevalence of such influences w addictions compared to those without

  - once identified, these can then be used to target preventative measures
• risk factors - genetic vulnerability


  - the evidence that the probability of developing an addiction [partic substance addiction] has a genetic factor is thought to be quite strong

  - can be assessed w twin s/adoption s

  > there are two genetic mechanisms identified as potentially incr the chance of dvlping an addiction

  * density of dopamine receptors &

  & * rate of metabolism
• risk factors - genetic vulnerability ; genetic mechanisms 1. density of dopamine receptors


  - there are diff types of dopamine receptors & a low density of D2 receptors [which is genetically determined] linked w addiction
• risk factors - genetic vulnerability ; genetic mechanisms 2. rate of metabolism


  - the speed w which substances are broken down in the body is linked to addiction

  > e.g. CYP2A6 is an enzyme that metabolises nicotine & some ppl do not have this enzyme at a fully-functioning level

  > & such ppl tend to smoke less than those who enzyme is fully functioning
• risk factors - genetic vulnerability ; evidence


  evidence for a genetic factor comes from family studies

  - Kendler et al. [2012] compared adoptees from bio families that had at least one parent w an addiction with adoptees that had bio parents w/o any addictions

  - those w at least one bio parent w an addiction had a 8.6% chance of dvlping an addiction themselves compared to just 4.2% of those w non-addicted bio parents
• risk factors - genetic vulnerability ; indirect influences of genes on addiction


  - factors such as personality, risk-taking behavs, self-control & emotional regulation have been shown to potentially be at least in part determined by genetic factors

  - all of the above can be seen to have role in the formation of addiction & therefore further incrs the influence genes might have in addiction
• risk factors - stress ; study


  can act as risk factor for dvlping addiction under certain circumstances, as demonstrated by a study by Epstein et al [1998]

  > women who had expd childhood rape & diagnosed w ptsd later in life had a high prevalence for alcohol

  > while those w historic rape & no diagnosis of ptsd did not
• risk factors - stress ; findings & conclusions


  - suggests childhood trauma is only a risk factor if later paired w a stressful life incident [e.g. d/s model of addiction]

  - Anderson & Teicher [2008] suggests the trauma in childhood occurs at the time of sensitive dvlpment, thus creating a vulnerability to later addictions
• risk factors - personality


  - while the idea of an 'addictive personality' holds little away in psych, there are personality traits that are associated a incr risk of dvlping addiction

  - antisocial personality d [aspd] is partic associated w addic,

  > d is characterised by impulsivity; lack of planning, high risk taking, chaotic lifestyle

  - it is spec that aspd & addic may share a neurological basis & may be related genetically
• risk factors - family influences


  - several mech may be at play here [slt [role m, exposure] but

  - key factor: perceived parental approval; the extent to which an adolescent believes their parents has a posi attitude to focus of addic

  - Livingston et al. [2010] showed how high-school students permitted to drink alcohol at home were signif more likely to drink excess at college
• risk factors - peers


  - the strength of peer influence incrs w age

  - O'Connell et al. [2009] suggests 3 elements of peer influence that incr the risk of addic to alcohol

  * influ perceived social norms

  * incr opp to use alcohol

  * over-estimating peer use & drinking more to keep up w this perceived consumption

  - a perceived norm of 'rule-breaking' will also act as risk factor for addic to other drugs too
• risk factors - evaluation ; interaction


  - the risk factors identified don't work in isolation, it is the combinations of diff factors tht tend to show the strongest predictive value for addic formation & severity

  - & risk factors can act as protective factor [e.g. some personality traits may make addics less likely to occurs] counteracting the risks

  - this creates a more complex pic than looking at each rich factor in isolation
• risk factors - evaluation ; types of evidence


  - most of the research is aimed at establishing if there is a correlation between the risk factors & the prevalence of addic

  - therefore, difficult to establish whether one condition affects the other, a=b or b=a or maybe c=a/b & cannot establish c&e

  - &, research looking at childhood & fam factors will typic depend on retrospec accs - it can lack in reliability as recollection may be inaccurate
• risk factors - evaluation ; proximate & ultimate risk factors


  - many of the risk f may ultimately have at least in part a genetic component

  - e.g. the personality trait of novelty-seeking is associated w genetic markers for D4 dopamine receptors

  > it also associated w an incr of alcoh addic, poten due to an incr reward [from more sensitive dopam system] when using a substance

  - novelty-seeking is, therefore, a proximate risk f due to its immediate effect, but the underpinning genetic f is the ultimate risk f
• risk factors - evaluation ; applications


  - one strength of establishing risk factors is they can then be used to target strategies to help at risk groups avoid addictions
• expl for nicotine addiction ; learning theory - behavioural explanations


  - habitual smokers using products w/o nicotine [e.g. vaping] report similar lvls of enjoyment to those using nicotine

  - & may have withdrawal symptoms similar to those experienced by nicotine users, which suggests there is more nicotine addic than a chemical addic

  - learning theory's mechanisms of classical & operant conditioning offer some insight into what these might be
• expl for nicotine addiction ; learning theory - operant conditioning: positive reinforcement


  > adding a desirable stimulus [pleasure from smoking] that incrs the likelihood the preceding behav [smoking] will be repeated

  - if the behav of smoking is perceived as rewarding [e.g. due to its chemical action on dopamine,] it is predicted to be more likely to reoccur by posi rein

  - this can expl initial formation of nicotine addic
• expl for nicotine addiction ; learning theory - operant conditioning: negative reinforcement


  > removing an undesirable stimulus [withdrawal effects] that incrs the likelihood the preceding behav [smoking] will be repeated

  - withdrawal from nicotine has several unpleasant effects: reduced concentration [cog] disturbed sleep [behav,] mood disturbance [emo]

  - smokers will avoid these effects by maintaining their nicotine levels & neg reinforcing smoking behav
• expl for nicotine addiction ; learning theory - classical conditioning [primary & secondary reinforcers]


  - this pleasure from smoking is a primary reinforcer as it has a direct & intrinsic rewarding effect [through its action on dopamine]

  - any other stimuli present at the time may become associated w this pleasure [as predicted by classical c] becoming a secondary reinforcers

  - smoking being associated with meals: > ucs= smoking > ucr= :) > ns/cs= finish meal > nr=neural > cr = :)
• expl for nicotine addiction ; learning theory - classical conditioning [secondary reinforcers & cue reactivity]


  - in addition, these secondary reinforcers act as cues to smoking behav [they bring smoking to mind & incr desire to engage in smoking behav]

  - the response to such stimuli is referred as cue reactivity, & has three main elements

  > self-reported incr desire to smoke

  > physiological responses [incr heart, rate, galvanic skin response]

  > incr smoking behavs [more 'drags, depth of 'drags']
• expl for nicotine addiction ; learning theory - evaluation ; non-human studies


  - Levin et al. [2010] allowed mice to self-administer intravenous doses of nicotine through the choice of 1 or 2 waterspouts

  - mice would favour the spout that allowed the release of nicotine & this incr on subsequent trials

  - supports posi reinforcm of behav due to the effects of nicotine
• expl for nicotine addiction ; learning theory - evaluation ; non-human studies [generalisability]


  - generalisability = humans have diff psych to mice, we have lang, communication e.g. facial expr & conscious awareness about health risks so lack it

  - however, there is a degree of generalisability as we are looking at bio, same brain structures, organisations
• expl for nicotine addiction ; learning theory - evaluation ; cue reactivity


  - a meta-analysis by Carter & Tiffany [1999]

  - 41 studies into the self-reported craving & objective measures of physiological responses [e.g. heart rate, galvanic skin response] from cues [e.g. ashtrays, lighters & cigarette packets] presented to addicts & non-addicts

  - supports that addicts react more strongly than non-addicts to such cues [as predicted by cue reactivity theory]
• expl for nicotine addiction ; learning theory - evaluation ; applications


  - the theory of behav mechanisms in nicotine addic has led to treatments based on these theories, such as aversion therapy which have demonstrated to be more effective for attempts to cess smoking compared to no therapy

  - Smith [1988] 52% still abstaining after 1 year using aversion therapy compared to 25% without
• expl for nicotine addiction ; learning theory - evaluation ; limited explanations


  - less than half of adolescents that experiment w smoking go on to become dependent

  - some may smoke occasionally or even daily but not exp withdrawal symptoms

  - this is a difficulty for theories w a limited no. of processes to expl as there are likely to be numerous factors involved [peers, family influence, biological vuln, personality, stress]
• expl for nicotine addiction ; neurochemistry


  - various chemicals regulate the functioning of the nervous system incl psych functions

  - two important neurotransmiters involved in the action of nicotine & subsequent addiction:

  > Acetylcholine [ACh]

  > Dopamine

  - in addition, there are the various receptors that these can bind w on post-synaptic neurons; having an excitatory or inhibitory effect
• expl for nicotine addiction ; neurochemistry -desensitisation hypothesis [nAChR] 1.


  - Acetylcholine is distributed widely through the nervous system & is associated w multiple functions

  - it has a variety of associated receptors

  - of interest to studying nicotine are the nicotinic acetylcholine receptors [nAChR] that bind with & stimulated by both ACh & nicotine [agonists for nAChR]
• expl for nicotine addiction ; neurochemistry -desensitisation hypothesis [downregulation & desensitisation] 2.


  - however following excitation from nicotine, the nicotinic receptors shut down, reducing the number of active receptors [downregulation]

  - this makes the neuron less sensitive & more difficult to fire [desensitisation]
• expl for nicotine addiction ; neurochemistry - desensitisation hypothesis [NAcc & dopamine reward system] 3.


  - desensitisation triggers the release of dopamine in an area of midbrain known as the nucleus accumbens [NAcc,]

  - which forms part of the dopamine reward system

  - this produces feelings of pleasure, reduces anxiety & increases alertness [the psych effects of nicotine]

  - this mechanism is similar to what occurs n drugs like cocaine & amphetamines
• expl for nicotine addiction ; neurochemistry - nicotine regulation model [upregulation] 1.


  - nicotine is naturally metabolised by enzymes [e.g. CYP2A6] & removed from the body, allowing ACh receptors to regain function [upregulation] & sensitivity

  - the incr in activity of ACh has the effect of incr anxiety/agitation & decr lvls of dopamine [nicotine withdrawal syndrome]

  - after prolonged periods without nicotine, the smoker will start to feel these effects & be motivated to remove them by having a cigarette