Describe the reward circuits thought to underpin substance use and abuse Can addiction be understood purely within biological terms

An estimated 2 billion people use alcohol and other substances. An estimated 500 million are addicted to drugs and alcohol.Addiction is a condition that comes about as a result of a person ingesting substances such as alcohol, nicotine, morphine, and cocaine among others or being a participant in an activity that is pleasurable to the extent that it becomes compulsive, and interferes with a person’s ordinary life roles and responsibilities. However, some individuals are able to use substances and not incur the negative effects or even be addicted. As for the many others, substance use and abuse results in problems at school, work, and homes, as well as in relationships. Therefore, drawing on a variety of sources the paper will discuss the reward circuits thought to underpin substance use and abuse. Furthermore, the research paper will evaluate the factors that lead to addiction and eventually give a conclusive summary on which factor appears more responsible for addiction.Even though all drugs have various psychological and physical effects, all abused substances have one thing in common. continual use alters the manner in which the brain functions. If one takes recreational drug, it causes an increase in the dopamine levels triggering a feeling of pleasure (Malenka, Nestler, amp. Hyman, 2009). The brain remembers this feeling and wants them again. The same effect is demonstrated when one uses illicit drugs (Pickens amp. Svikis, 2009). The uncontrollable craving grows because the brain is used to being triggered by ingestion of certain substances. Therefore, one starts experiencing problems because of the changes in the functioning of the brain interfere with one’s ability to think, control their behaviour, perform good judgement, and a normal feeling without drugs.Addiction can be understood purely within biological terms based on the reward system. According to Kendler et al. (2012), a reward is usually an appetitive stimulus that is given to living