Created by showmestarlight over 5 years ago
Biological ExplanationInitiationThe role of genetics - family and twin studies estimate the heritability of tobacco smoking to be between 39% and 80%. Vink et al. (2005) studied 1,572 Dutch twin pairs. They found that for both males and females individual differences in smoking initiation were explained by genetic (44%) and environmental (56%) influences. Likewise, a US study of 348 identical twin pairs and 321 same-sex fraternal twin pairs estimated the heritability for regular smoking to be 42% (Bordman et al., 2008).MaintenanceThe effects of nicotine - Vink et al. also reported that nicotine dependence was influenced by genetic (75%) factors, which suggests that regular tobacco use is linked more strongly to individual differences in nicotine metabolism. Nicotine affects brain chemistry by activating nicotine acetylcholine receptors in the brain, which leads to the release of dopamine. These chemical reactions create short-lived feelings of pleasure for the smoker, who then experiences impairment of mood and concentration within hours of their last cigarette as nicotine levels drop in their blood. These effects can be alleviated by smoking another cigarette. Smokers repeat this cycle many thousands of times in order to avoid withdrawal symptoms when not smoking. Pre-natal exposure to nicotine - research suggests that mothers who smoked heavily while pregnant were more likely to have children who, should they start smoking, were more likely to become addicted.RelapseTwin studies suggest that the ability to quit smoking is also subject to genetic influences. For example, Xian et al. (2003) carried out a twin study to test whether genetic risk factors contributed to failed attempts to quit smoking. They found that 54% of the risk for quit failure could be attributed to heritability. Research (e.g. Uhl et al., 2008) has also attempted to identify the specific gene clusters associated with quit success and with nicotine dependence, with the aim of matching specific anti-smoking treatments with the smokers most likely to benefit from them.
Cognitive ExplanationInitiationAddicts differ from non-addicts in terms of their expectancies about positive versus negative effects of behaviour. Expectancy theories propose that a behaviour escalates into addiction because of the expectancies that an individual has about the costs and benefits of that activity. Adolescent smokers commonly report smoking when they are experiencing negative moods and expect that smoking will decrease the intensity of their negative mood. The expectancy of positive mood states (such as relaxation and increased self-confidence) has also been shown to be a reason for adolescents beginning to smoke. MaintenanceBrandon et al. suggests that as an addiction develops, the activity is influenced less by conscious expectancies and more by unconscious expectancies involving automatic processing. This would explain the loss of control that many addicts experience in their addictive behaviour and the difficulties they experience in abstaining. Expectancies can also be manipulated to prevent relapse. Tate et al. told smokers that they should expect no negative experiences during a period of abstinence. This led to fewer reported somatic effects and psychological effects than a control group who were not so primed. RelapseExpectations of the costs and benefits of smoking affect an individual's readiness to quit and also the likelihood of them relapsing after they have quit. Several studies have demonstrated that smokers' perceptions of quitting affect their quitting behaviour. According to this perspective, those individuals who perceive smoking to have many benefits and quitting to have relatively few are the ones most likely to relapse and revert to smoking after embarking on a quit attempt.
Behavioural ExplanationInitiationAvailability of role models - social learning theory explanations of experimental smoking propose that young people begin smoking as a consequence of the social models they have around them who smoke. From this perspective, experimental smoking is primarily a function of parental and peer role modelling and the vicarious reinforcement that leads young people to expect positive physical and social consequences from smoking. Popularity as a positive reinforcer - popularity among peers may also serve as a positive reinforcer in the initiation of smoking. Mayeux et al. (2008) found a positive relationship between smoking at age 16 and boys' popularity two years later. Maintenance The repetition of the act of smoking thousands of times a year eventually leads to a strong conditioned association between the sensory aspects of smoking (the sight of cigarettes, smells of the smoke, etc.) and the reinforcing effects of nicotine. Although the effects of nicotine in the brain are important when first starting smoking, smoking-related sensory cues rapidly become conditioned stimulus and so activate the same brain areas, making cessation more difficult. RelapseConditioned cues - cues associated previously with receiving nicotine, such as the availability of cigarettes or the smell of cigarette smoke, increase the likelihood that the smoker will respond by smoking. Hogarth et al. found that the amount of craving increased significantly when a conditioned stimulus related to smoking was presented to a new smoker.Refusal self-efficacy - a concept related to the social learning explanation of smoking is self-efficacy, a person's belief in his or her ability to succeed in a particular situation. Among adults, those who smoke more frequently have less confidence in their ability to abstain (Lawrence and Rubinson, 1989) and so are more likely to relapse.
Biological ExplanationInitiationThe role of genetics - studies have shown that pathological gambling runs in families. Although many attribute this to social-modelling influences, it is also possible that it could be due to genetic as well as environmental factors. A twin study by Shah et al. (2005) found evidence of genetic transmission of gambling in men. Black et al. (2006) found that first-degree relatives of pathological gamblers were more likely to suffer from pathological gambling than more distant relatives were, therefore demonstrating a strong genetic link.MaintenanceThe pituitary-adrenal response - Paris et al. measured Gamblers' cortisol (the stress hormone associated with the pituitary adrenal response) levels before and after watching a video of their preferred mode of gambling and a video of neutral stimuli (a roller coaster ride). Recreational gamblers had significantly increased salivary cortisol levels after both videos, while pathological gamblers had no increase in response to either video.Sensation-seeking - Zuckerman claimed that there are individual differences in the need for optimal amounts of stimulation. Sensation-seekers look for varied or novel experiences. High sensation-seekers have a lower appreciation of risk and anticipate arousal as more positive than low sensation-seekers do and therefore are more likely to gamble.RelapseBoredom avoidance - the pathological gambler is seen as a person who needs this intense stimulation and excitement. Blaszozynski et al. (1990) found that poor tolerance for boredom may contribute to repetitive gambling behaviour. Pathological gamblers had significantly higher boredom proneness scores than control groups of non-gamblers. There were no significant differences between the different types of gambling (e.g. betting on horses, slot machines, etc.).
Cognitive ExplanationInitiationThis model proposes that individuals intentionally use different forms of pathological behaviour (e.g. alcohol, drugs, binge eating and pathological gambling) to treat the psychological symptoms from which they suffer. The particular activity an addict chooses is not selected at random but tends to be one that is perceived as helping with a particular problem. For example some activities may be chosen because they help the individual overcome anxiety, whereas others, such as gambling, appear to help with the depression associated with poverty, and so on. This is known as self-medication.MaintenanceDespite the objective probability of failure related to any games based on chance, problem gamblers frequently have irrational perceptions about their ability to influence the outcomes of their gambling. Cognitive distortions associated with gambling include the 'gambler's fallacy', i.e. the belief that completely random events such as a coin toss are somehow influenced by recent events. For example, runs of a particular outcome (two or three heads in a row) will be balanced out by the opposite outcome (the same number of tails). Illusions of control are demonstrated through the performance of superstitious behaviour, which the gambler believes helps them to manipulate the event outcome in their favour. Pathological gamblers may also show an exaggerated self-confidence in their ability to 'beat the system' and influence chance. RelapsePathological gamblers often suffer from a 'recall bias', i.e. the tendency to remember and overestimate wins while forgetting about, underestimating or rationalising losses (Blanco et al., 2000). Consequently, a string of losses does not always act as a disincentive for future gambling. Such individuals believe they will eventually be rewarded for their efforts and could be motivated to return on subsequent occasions because of a belief that they 'deserve' to win, having lost so often on previous occasions (the 'just world' hypothesis).
Behavioural ExplanationInitiationOperant conditioning proposes that any behaviour that produces a consequence that the individual finds rewarding, then becomes more frequent. Griffiths (2004) argues that gamblers playing slot machines may become addicted because of physiological rewards (e.g. getting a buzz from winning), psychological rewards (e.g. the near miss), social rewards (e.g. peer praise), and financial rewards if they win. This may seem strange given that the gambler usually loses but, as Delfabbro and Winefield (1999) point out, gamblers are not always rational in their thinking and greater weight may be given to the experience of winning.MaintenanceIntermittent reinforcement - the operant conditioning model proposes that people continue to gamble because of the intermittent (i.e. occasional) reinforcement that is characteristic of most types of gambling. As a result, they become used to long periods without reward and their gambling behaviour is reinforced by the occasional payout.Social approval - this type of behaviour may also be maintained because reinforcement is provided in the form of social approval from others. Lambos et al. (2007) found that peers and family members of problem gamblers were more likely to approve of gambling. Respondents who received this form of reinforcement for their gambling not only gambled more than other respondents but also intended to continue doing so in the future.RelapseConditioned cues - addicts learn (through classical conditioning) to associate other stimuli with their gambling behaviour (e.g. the sights and sounds of a casino or the presence of other gamblers). These stimuli act as triggers for gambling because they have the ability to increase arousal. If, after a period of abstinence, an individual comes into contact with one of these conditioned cues, they are at a higher risk of relapse. Approach-avoidance conflict - because gambling has both positive and negative consequences for the individual, they are motivated to approach and to avoid situations where gambling is involved. This creates an approach-avoidance conflict, where motivation fluctuates between wanting to gamble and wanting to stop. Whether or not the gambler will gamble when faced with an urge to do so is related to their ability to control the increased arousal and delay their need for reinforcement.