Biochemical Explanation for substance misuse:
Drugs are chemicals and they work in the brain to provide a pleasure reaction and, for some drugs, an addiction reaction. Prescribed drugs, such as tranquilisers and anti-schizophrenic drugs, work in the same way. The drugs act like other neurotransmitters – when released by an electrical impulse, the neurotransmitter chooses a synaptic gap to fit with receptors of another neurone. Drugs can also prevent the reuptake of a neurotransmitter, which means the neural transmission is blocked.
Dopamine and serotonin are linked to pleasure and positive emotions. Endorphins increase pleasure and reduce pain. Drugs act in much the same way as these neurotransmitters. They work in three different ways:
- they fit the receptors of a neuron and stimulate the same response as a similar neurotransmitter (agonist);
- they fit the receptors of a neuron and block access to the receptor, preventing the transmission of a signal (antagonist);
- they prevent the reuptake of neurotransmitters, so they remain at the synapse and are able to attach to the receptors (more availability of that neurotransmitter).
For example, cocaine stimulates the dopamine receptors , increasing the availability of dopamine messages (as there is more dopamine in the synaptic cleft).
——————————–>
Evaluation of the Biochemical Explanation:
-
Strengths:
- Biological explanations have validity because objective data demonstrate visible activity under certain circumstances. For example, PET scans have shown a difference in neuronal activity when smoking normal and low-nicotine cigarettes.
- Biological explanations are also supported by animal studies, which have reliability because they are highly controlled and replicable. For example, many animal studies have shown how different drugs affect receptors in different ways.
- Research in biopsychology is supported by findings in other areas of biology, which reinforces the biological explanation. For example, identification of the mu-opioid gene matches findings about the mu-opioid receptors.
Limitations:
- Biological explanations may not be reliable if animal studies show differences between animals. For example, different studies show differences in mice when studying different opioid receptors. This means that we should be cautious when generalising from animal studies to explanations of human behaviour.
- Although the findings of PET scans have some validity, we must remember that the behaviours being measured take place in an artificial environment, so the validity can still be questioned.
- Generalising the results from animal studies poses issues with validity. Human beings are not the same as animals, therefore the results obtained from these studies may not apply.
that psychology blog 