Addiction - 03 Explanations for nicotine addiction Flashcards
What is the main active ingredient of tobacco?
Nicotine
How is nicotine absorbed in the body?
through the lining of the mouth and nose and by inhalation in the lungs
How long does it take after inhalation for nicotine to reach peak levels in the bloodstream and the brain?
less than 10 seconds
What is the amin neurotransmitter of the reward system?
dopamine
What is dopamine involved in?
producing feelings of pleasure engage in behaviours which activate the reward system
How does nicotine act upon the brain’s reward system?
by heightening dopaminergic activity
What is the mesolimbic system?
reward and pleasure centre of the brain
Describe the steps of the dopamine desensitisation hypothesis
1)smoke a cigarette
2)nicotine enters bloodstream
3)nicotine enters brain
4)stimulates nicotinic acetylcholine receptors (nAChRs)
5)dopamine production in ventral tegmental area
6)dopamine transported to nucleus accumbens generating pleasure
7)reduces anxiety & increases alertness by increasing frontal cortex activity
8)stimulates release of glutamate which speeds up dopamine release
9)nicotinic acetylcholine receptors become desensitised after constant stimulation which lowers signal in reward pathway
10)results in higher tolerance
What does the nicotine regulation model say?
-periods without nicotine causes nAChRs receptors to become resensitised to nicotine (upregulation)
-having many nAChRs receptors available but not stimulated causes withdrawal symptoms
-smoking alleviates symptoms and negatively reinforces the behaviour
Why do smokers often find that the first cigarette of the day is the most satisfying?
during sleep nAChRs receptors are upregulated and become more sensitive, resulting in a greater dopamine release when smoking resumes
Strength of brain neurochemistry and its role in nicotine addiction - support for the nicotine-dopamine link
-Paterdon & Markou found epilepsy drug reduces surge of dopamine in nucleus accumbens
-so reduces addictive tendencies of nicotine, counteracting pleasant experience caused by dopamine
weakness of brain neurochemistry and its role in nicotine addiction - dopamine no the whole story
-nicotine is so addictive due to several complex explanations
-research revealing many other neurochemical mechanisms involved
-e.g. GABA and serotonin pathway
-BUT dopamine system is central and all other systems interact with it
weakness of brain neurochemistry and its role in nicotine addiction - reductionist
-reduces complexities of nicotine addiction down to level of neurotransmitters
-psychological aspects largely ignored
BUT COULD HAVE BENEFITS
-can lead to scientific research into area and development of appropriate treatment
strength of brain neurochemistry and its role in nicotine addiction - real life application
-greater understanding of neurochemistry led to forms of treatment like nicotine replacement therapy (patches, gum and vapes)
-shows usefulness of research in this area
weakness of brain neurochemistry and its role in nicotine addiction - not only factor & individual factors
-Studies chippers (people who smoke regularly but do not become dependent)
-those who smoked average 5 cigarettes a day showed no signs of withdrawal
-performed batter on cognitive task than dependent smokers
How does social learning theory say that smoking starts?
-young people observe and imitate role models (parents, peers, celebrities) around them who smoke
-vicarious reinforcement leads them to expect enjoyment from smoking
What is the role of positive reinforcement in nicotine addiction?
nicotine gives feeling of pleasure that is rewarding, so they want to experience it again by having another cigarette
What is the role of negative reinforcement in nicotine addiction?
stopping nicotine use leads to withdrawal symptoms which are unpleasant, so they will want to reduce these effects by smoking again
What is the role of classical conditioning in nicotine addiction?
-suggests smoking is learned through association
BEFORE CONDITIONING
hanging out with friends (UCS) = enjoyment & relaxation (UCR)
BEFORE CONDITIONING
cigarette (NS) = no response
DURING CONDITIONING
hanging out with friends (UCS) + cigarette (NS) = enjoyment & relaxation (UCR)
AFTER CONDITIONING
cigarette (CS) = enjoyment & relaxation (CR)
What is the role of cue reactivity in nicotine addiction?
-smoking often occurs in certain environments with certain people
-over time with repeated associations these become secondary reinforcers
-these act as cues as they produce similar physiological and psychological responses to nicotine itself
What are some examples of smoking cues?
lighters, ash trays, matches, specific places etc
strength of learning models of addiction - research support for cue reactivity
-meta-analysis
-dependent and non-dependent smokers presented with smoking related cues
-dependent smokers reacted strongly reporting high levels of craving and arousal
HOWEVER
-research shown young women more sensitive to smoking related cues
-learning theory does not explain these gender differences
-so cue reactivity may apply more to women than men
weakness of learning models of addiction - limited explanation
-no more than 1/2 people who experiment with smoking in adolescence go on to develop addiction
-also social smokers smoke occasionally but do not become dependent and experience withdrawal symptoms
-so must be several other causes of smoking
-learning theories too simplistic to adequately explain nicotine addiction
strength of learning models of addiction - real life application
-treatments been developed for smoking addiction based on classical conditioning
-aversion therapy aims to remove addiction by associating pleasurable effects with aversive stimulus
-this improves health, saves lives & reduces NHS spending
-also suggests that smoking is to some extent caused by and maintained by conditioning
