Animal Models of Addiction: A Review

The study of neural and cognitive pathways in addiction is one of the most important challenges of neuroscience. Addictive drugs stimulate the reward circuits, motivation, euphoria, cognitive changes, and motor activity. Several studies have shown that mesocorticolimbic pathway activity plays an important role in cognition and behavior activated by natural rewards and addictive substances. There is a significant relationship between substance-seeking behavior and decision-making, attention, learning, memory, reward, and substance use. The development of animal models of addiction is essential to our understanding of the substance addiction mechanisms and the cognitive symptoms that result from the continuation of addiction. In this study, we reviewed the various animal models of addiction and their contribution to our understanding of the pathophysiological mechanisms.

According to different routes of drug abuse in humans, there are different types of animal models that include different paradigms, such as inhaled, oral, and intravenous. Intracranial self-stimulation and conditioned animal models based on drug reward attempt to understand the neurobiological basis of addiction and subsequent drug-induced cognitive impairments. Conditioned place preference is one of the more widely used models to study the rewarding properties of drugs in the context of reward-related learning and measures an animal's ability to predict future rewards. Recently, these animal models have been used to simulate drug addiction to provide new perspectives for studying different phenomena, such as extinction, relapse, compulsive drug-seeking behavior, withdrawal syndrome, and drug-induced cognitive impairments. In summary, these innovations in animal modeling have allowed us to improve our knowledge of drug addiction and the biological basis of addiction-related cognitive disorders in the future.