Addiction - Explanations For Nicotine Addiction (Brain Neurochemistry Etc.)

Question 1

What is neurochemistry?

Answer 1

Chemicals in the brain that regulate bio & psych functioning

Question 2

What is dopamine?

Answer 2

A neurotransmitter, has an excitatory effect & is associated with pleasure.

Question 3

What condition are unusually high levels of dopamine associated with?

Answer 3

Schizophrenia

Question 4

What condition are unusually low levels of dopamine associated with?

Answer 4

Parkinson’s disease

Question 5

Who came up with the desensitisation hypothesis of nicotine addiction?

Answer 5

Dani & Heinemann

Question 6

What is the key neurotransmitter in the desensitisation hypothesis of nicotine addiction?

Answer 6

Acetylcholine

Question 7

What is the name of the receptors which are activated by acetylcholine or nicotine?

Answer 7

Nicotinic Acetylcholine receptors (nAChR)

Question 8

What happens when nAChRs are stimulated by nicotine?

Answer 8

The neurons release dopamine

Question 9

What pathway does the dopamine travel down?

Answer 9

mesolimbic pathway to nucleus accumbens -> triggers release of dopamine into frontal cortex

mesocortical pathway -> released directly to frontal cortex

Question 10

What are the mesolimbic & mesocortical pathways a part of?

Answer 10

the brain’s dopamine reward system

Question 11

What does nicotine do to the brain’s reward system?

Answer 11

It powerfully activates it -> results in pleasurable effects e.g. mild euphoria, alertness & reduction of anxiety

Question 12

How are the pleasurable effects of nicotine associated with smoking?

Answer 12

Operant conditioning

Question 13

What happens when an individual stops smoking?

Answer 13

nicotine disappears from their body -> nAChRs become active & dopamine neurons resensitise and are available (upregulation)

Question 14

How can neurochemistry explain the symptoms of withdrawal, dependence & tolerance?

Answer 14

During resensitisation nAChRs become overstimulated by acetylcholine (no nicotine) -> most sensitive

to avoid unpleasant physiological & psychological withdrawal state -> go through constant cycle of daytime downregulation & nighttime upregulation (creates longterm desensitation of nAChRs) -> dependence

continous exposure causes physical changes to the brain (decrease in number of active receptors -> tolerance develops)

Question 15

EVALUATION: What research support from McEvoy et al supports the desensitisation hypothesis of nicotine addiction?

Answer 15

Studied smoking behaviour in people with schizophrenia who were taking Haloperidol (antipsychotic) -> dopamine antagonist
People taking the drug showed increase in smoking (form of self-medication ) -> shows dopamine has key role in the neurochemistry of nicotine addiction

Question 16

EVALUATION: What real world application is a strength of brain neurochemistry as an explanation of nicotine addiction?

Answer 16

Nicotine replacement therapy -> developed after nicotine was identified as addictive & had affects on nAChRs
NRT products (gum/patches etc) deliver controlled dose of nicotine -> binds to nAChRs and mimics effects
Helps with cravings and gradually reduce withdrawal symptoms -> greater understanding neurochemistry led to effective treatments

Question 17

EVALUATION: What does Gilbert say about the limitations of the brain neurochemistry explanation for nicotine addiction relating to withdrawal symptoms?

Answer 17

Argues withdrawal symptoms depending on amount of nic in body is not strongly correlated -> depends on environment & personality (people who score high on the personality of neuroticism generally experience worse withdrawal symptoms then those who are emotionally stable) -> withdrawal effects can be explained in other ways without reference to amounts of nicotine

Question 18

EVALUATION: How can the brain neurochemistry explanation of nicotine addiction by biologically deterministic?

Answer 18

Suggests we become addicted due to chemical events regarding dopamine that is beyond our control (inevitable for smokers)
Some dont experience withdrawal symptoms/dependence & some find it easier to quit due to their personality