Explanations for Nicotine Addiction - Brain Neurochemistry Flashcards
Outline brain neurochemistry as an explanation for addiction (6 marks)
Brain neurochemistry states that a nicotine addiction is formed due to the repeated activation of the brain’s reward pathway. An individual smokes a cigarette and inhales nicotine, which reaches the blood stream and activates nicotinic acetylcholine receptors (nAChR) in the ventral tegmental area (VTA) of the brain in less than 10 seconds. Dopamine is released from the VTA down the mesolimbic pathway to the D2 receptors on the nucleus accumbens (NAc) responsible for the feeling of euphoria and relaxation. When dopamine reaches the NAc this triggers release of more dopamine from the NAc down the mesocortical pathway to the pre-frontal cortex which is responsible for what we pay attention to and the person then makes the decision to smoke again to experience to the same pleasurable feelings. Therefore, explaining why people repeatedly smoke and become addicted to nicotine.
Discuss brain neurochemistry as a factor affecting addiction (3 X AO3)
Research to support support brain neurochemistry and the role of dopamine was conducted by Mc Evoy. They studied smoking behaviour in people with schizophrenia who were taking a drug. This drug is a dopamine antagonist by blocking dopamine receptors - lowering the level of dopamine activity in the brain. It was found that the people taking the drug showed a significant increase in smoking. Therefore, supporting the role of dopamine as an explanation of addiction to nicotine, as the patients sought nicotine in order to increase their level of dopamine in the brain and experience euphoria.
Moreover, Brain neurochemistry as an explanation of nicotine addiction can be criticised for biological reductionism. This is because the theory reduces the complex human behaviour of nicotine addiction down to dopamine levels within the brain. This neglects a holistic approach, which takes into account how a person’s cultural and social context would influence and explain an individual’s nicotine addiction, for example adolescents may develop a nicotine addiction due the wanting to fit in with a particular peer group, rather than the feeling of euphoria. Therefore, the brain neurochemistry explanation of nicotine addiction may lack validity as it does not allow us to understand the behaviour in context.
The brain neurochemistry explanation of nicotine addiction has practical applications. This is because the principles of the theory, that nicotine addiction is caused by high levels of dopamine and an activation of the brain’s reward pathway has led to the treaTment of nicotine replacement therapy (NRT). This is effective in reducing nicotine addiction by providing the individual with nicotine in a less harmful form such as a patch instead of a cigarette and slowly reducing the dosage overtime, thus reducing the individual’s tolerance. Therefore, the brain neurochemistry explanation of nicotine addiction is an important part of applied psychology when helping to treat nicotine addiction in the real world.
