Drugs Rosenburg and Seligman define substance abuse as
Drugs �Rosenburg and Seligman define substance abuse as: Heavy, daily use Compelled to keep taking the substance Problems with social life due to the drugs Strong dependency Difficulty in holding down relationships Long-term use
Substance Abuse Psychological Dependence – when a user feels that a drug is necessary for their health and well-being. � Use is continued despite knowledge of its negative health or social consequences, despite efforts to reduce consumption. � Relapse – when substance use begins again after a period of abstinence or remission � Salience � Euphoria Physical Dependence – when the body adapts to a drug to the extent that it shows tolerance and withdrawal � Tolerance – increasing amounts of drug are needed to achieve the same desired effect � Withdrawal – the body suffers from detrimental effects when the substance is stopped
Drugs � Dopamine Linked to the feeling of reward for experience like food, water and sexual activity. When dopamine receptors are blocked, the “reward” section of the brain is not active, and so behaviour is not repeated Stimulants of dopamine inhibit it’s reuptake, so it’s affects last longer After dopamine stimulation, the body negative feedback cycle means that less dopamine is released after, so uses of stimulants end up ‘crashing’, as the body produces ; ess natural dopamine This can be responsible for the addiction, through negative reinforcement (to take away this “crashing” effect) � Serotonin Associated with emotional functioning and perception of light and colour Affected by hallucinogens, but naturally responsible for elevated mood associated with pleasurable activities Drugs that increase the serotonin in the body: � � � Induce pro-social behaviour (‘hug-drug’) Intensify perception of light, colour and sound Increase body temperature and heart-rate
Drugs �Alcohol Effect on neurotransmitters � Lowers levels of noradrenaline receptors in the brain, resulting in drowsiness and impaired sensory functioning � It is popular due to these amnesic affects Short-term effects � Psychological Lowers social inhibitions • Allowing behaviour such as sociability, enjoyment or aggression Lowers reaction time, co-ordination, memory and alertness � Physical Increases inhibitory effects of neurotransmitter GABA (responsible for inhibiting responses in the body) • suppressing arousal centres slowing cognitive functions, and affecting movement and balance in the cerebellum
Drugs �Alcohol Long-term effects Psychological • Psychological dependence forms, which can cause major disruption to normal social, occupational and recreational activities. • Depression • Sarafino (1994) found that 10% of drinkers in the US abuse alcohol Physical • • • Cirrhosis memory loss increased vulnerability to infection (up to 2 x) Severe withdrawal symptoms Can impair dendritic branching of neurons Inhibits flow of sodium across neuron membrane, affecting electrical transmission • Decreases serotonin activities
Drugs �Alcohol Withdrawal and Relapse � Abstinence when highly dependent on alcohol leads to delirium tremens, which includes intense anxiety, irritability, nausea, headaches, body tremors and frightening hallucinations. � In most severe circumstances, death can result from this withdrawal � Strong cravings and impulses to drink lead to frequent relapse
Drugs �Heroin Effect on Neurotransmitters � Heroin increases dopamine activity � Although GABA decreases dopamine activity, opiates block the cells that produce GABA. � Without the release of GABA, there is nothing blocking the release of dopamine Short-term effects � Psychological Intense feelings of euphoria and pleasure Followed by longer-lasting, pain-dulling and numbing effects � Physical Heroin binds with the body’s natural pain-killing enkephalin and endorphin receptor sites (because it has a similar structure that mimics the neurotransmitter) It then breaks down into morphine, which has similar, but less powerful effects
Drugs �Heroin Long-term effects � Psychological dependence forms that causes life disruption Increased and persistent anti-social behaviour to gain the drug to avoid the withdrawal symptoms of depression and anxiety � Physical Prolonged use leads to a fast physical addiction The brain adapts by producing less natural endorphins and enkephalins Kendall and Hammen (1995) found that experienced users could tolerate 5000% higher dose than first-time users There can be death by overdose, and sharing needles can results in HIV
Drugs � Heroin Withdrawal and tolerance � � � Withdrawal symptoms can occur as quickly as 6 to 8 hours after the last dose, usually lasting about a week (peaking within 2 days) Symptoms vary depending on the tolerance reached Can include such withdrawal symptoms such as � Physical discomfort Diarrhoea Chills Goosebumps on the skin Twitching on extremities (e. g. leg twitching) Irritability With this intense physical strain, relapse is very common � Evaluation With all drugs, risk of relapse after withdrawal or physical dependency decreases with age, and is triggered by high-risk situations (e. g. social pressures, modelling of use or conflict, negative emotional state etc. )
Biological Explanations � Chemical Transmissions Neurons � A neuron is a cell that is used to send electrical impulses throughout the body. � � � It consists of a soma (cell body), the dendrites, the nucleus, and the axon, which is covered by a myelin sheath (which allowed insulation of the axon, and allows fastest, most efficient signals to be carried) Neural receptors are the area on the post-synaptic neuron, that receive the signal from the previous neuron. They are like the ‘lock’ that the ‘key’ (neurotransmitter) fits into. They allow reactions to be stimulated by the neurotransmitters. Electrical transmission involves signals being sent through an axon by electrostatic forces. Chemical transmission involves neurotransmitters crossing the synaptic gap. Nervous system � Divided into CNS and peripheral nervous system PNS is sub-divided into somatic nervous system (controlling voluntary movement) and autonomic nervous system (ANS - controlling involuntary movement) • The ANS consists of the sympathetic nervous system (preparing body for action), and the parasympathetic nervous system (restoring normal bodily function – opposite to sympathetic branch) The Endocrine system � A series of of glands that release hormones into the body The function is to maintain consistent state of the body
Biological Explanation of drugs effect �Electrical Transmission Due to the gradient of concentration and electrostatic attraction, K and Na try to swap, and take their charge with them A sodium-potassium pumps out Na and K on a ratio of 3: 2, to keep the balance during the resting potential Action potential � � The charge becomes +ve, and the partially permeable membrane widens, allowing more Na to get in, and no K to get out. The neuron becomes +vely charged – depolarisation It needs to return to a polarised state in order to send more messages, so as more ions leave, the pump begins to work again Anaesthetics � � � Novocain – attaches itself to Na+ gates opening, to stop Na+ entering. No signals can be sent, therefore no pain messages can be sent. Scorpion venom – works by keeping the Na+ gates open, and closes K+ channels, so the membrane remains +vely charged, and cannot send any message Chloroform – opens K+ gateways very wide, so the K+ can escape, and membrane does not become +vely charged, and so no messages are sent
Biological Explanation � Chemical Transmissions Neurochemicals pass over the synaptic terminals on to the receptor sites in the post-synaptic terminals When the action potential reaches the end of the axon, the depolarisation causes the stimulation of the vesicles within the pre-synaptic terminals � The vesicles move towards the end membrane of the terminal, and they merge with the membrane, releasing their contents into the synaptic cleft � It attaches to the receptor site on the next neurone, and the message is passed on There are two- types of receptor sites on both the pre- and post-synaptic terminal � • Autoreceptors detect released neurotransmitters that has not been absorbed, and stop further release • Heteroreceptors respond to neurotransmitters by either exciting or inhibiting presynaptic terminal increasing or decreasing release of neurotransmitter � Each neuron only produces a limited number of neurotransmitters
Factors affecting drug abuse �Learning theory/Behaviourism �Drugs are either positively reinforcing, they give us feelings we enjoy and so want to repeat; or they are negatively reinforcing, they take away feelings of unpleasantness, such as stress or withdrawal effects. �Social learning theory suggests we learn by modelling others, e. g. , family & peers �Operant conditioning can explain why we maintain drug habits, but not why we might acquire in the first place, for instance, people’s first experience of smoking or alcohol is often not pleasant. �Evidence for patterns of addictive behaviour in families can be explained by genetics.
Factors affecting drug abuse �Cognitive factors – we may have certain beliefs, attitudes and expectations regarding drugs which can influence our behaviour. We may develop certain cognitive ‘constructs’ for the outcomes of drug use. E. g. , Fromme et al (1997) suggests that early experiences or observations of alcohol use tend to have positive rather than negative outcomes, therefore, giving rise to certain expectations regarding alcohol use.
Factors affecting drug use � Psychological factors � Euphoria – people associate certain drugs with intense pleasure. This pleasure is often short-lived so people have to continue to take the drug in increasing amounts, due to tolerance, to experience the same euphoric feelings, and this can lead to physiological & psychological addiction. � Personality characteristics – Research by Mc. Cann & Ricaurte (1993) compared the personalities of 30 ecstasy users with 28 non-ecstasy users. The ecstasy users were less hostile & showed greater restraint & control – aspects of behaviour thought to be mediated by serotonin, a neurotransmitter affected by MDMA. � However, it may be that MDMA affects personality this way, rather than certain personality types being drawn to this particular drug. � Sensation seeking is a personality trait associated with risky behaviour, including drug taking. � Research by Zuckerman (1994) has shown that sensation seeking individuals can be characterised by a willingness to take financial, physical, social & legal risks in order to fulfil desire to find & engage in novel, complex & intense sensations & experiences. Sensation seekers seem to be more likely to smoke, abuse alcohol & use cannabis.
Factors affecting drug addiction � Social/cultural factors � Society’s attitudes & cultural norms regarding drugs can have a profound affect on drug misuse. � Seemingly behaviours associated with excess amounts of alcohol are at least partially learned. In the � � � West drunken people become depressed, aggressive & lose self-control; however, in Tahitians are peaceful & civil when under the influence of alcohol (Mac. Andrew & Edgerton, 1970). Sussman & Ames (2001) have shown that drug abuse is higher in areas closer to major drug distribution centres (like New York & Los Angeles), I. e. , ease of acquisition is a factor in abuse. Frone (2003) has shown that workplace availability can also be a risk factor in drug abuse, especially on-the-job alcohol & cannabis use. Wills et al (1996) found that ads linking smoking to social popularity & sensation-seeking cues were influential in the onset of smoking. However, Rushton (1997) suggests that research on young people fails to consider individual’s own drug knowledge & insight. People have different drug use ‘careers’ making it hard to identify specific cultural trends. Despite being exposed to similar cultural and social influences, not everyone abuses drugs or uses drugs in the same way to the same effect. Studies by Blaxter (1990) & Power et al (1991) have shown a relationship between social class & alcohol consumption, with young working class being worst affected.
- Slides: 16