Biological Explanations

Biological Explanations of Addictive Behaviours

Genetic Factors

• Twin studies have shown higher concordance rates of addiction among identical twins compared to fraternal twins, suggesting a genetic component.
• Genes linked to addiction have been identified: DRD2 is associated with dopamine, the neurotransmitter involved in feelings of reward and pleasure.
• Polygenic inheritance suggests many genes contribute to addiction, each having a small effect.

Neurotransmitters

• Dopamine is associated with feelings of pleasure and reward. High levels of dopamine are released during addictive behaviour.
• Some individuals may have a dopamine deficiency, making them more likely to seek out behaviours that increase dopamine levels.
• Studies have also highlighted the role of the GABA neurotransmitter. Decreased GABA function may make individuals more prone to anxiety and addiction.

The Brain’s Reward System

• The mesolimbic dopamine system, or the brain’s reward pathway, is implicated in addiction.
• This system releases dopamine, which leads to feelings of pleasure. With repeated exposure, the brain starts associating certain behaviours or substances with this reward.

Brain Structures

• The amygdala plays a role in the memory of the rewarding effects of addictive behaviour, and also in withdrawal symptoms.
• The prefrontal cortex, involved in decision-making and impulse control, is less active in individuals with addiction.

Biological Sensitivity to Substances

• Some individuals may be biologically more sensitive to the effects of addictive substances, increasing the risk of addiction.
• The ‘telescoping effect’ suggests women may progress from substance use to addiction faster than men due to biological differences.

Remember, biological explanations offer only one perspective on addiction. A comprehensive understanding necessitates considering other factors such as psychological and socio-cultural perspectives.