Explain the neuroplastic changes involved in addiction

Addiction leads to neuroplastic changes in the brain, particularly within the reward circuitry involving dopamine. Drugs of abuse, like cocaine and opioids, induce significant plasticity in the synapses of neurons within key areas such as the nucleus accumbens. These synapses are the connections from other nerve cells onto dopamine neurons, and drugs cause marked changes that alter the neuron's activity. These modifications make the brain's reward system more sensitive to the drug, which explains why individuals develop a persistent desire to seek these substances despite any initial dislike. Moreover, although these changes are not permanent or irreversible, they can last for a long period, further complicating the cycle of addiction. These alterations are akin to those observed in adaptive learning and memory processes, underscoring the enduring impact of substance use on neural circuitry 1 2.