Compose a 1250 words assignment on addiction as one of the major issues of the human race.

Compose a 1250 words assignment on addiction as one of the major issues of the human race. Needs to be plagiarism free! Addiction to a substance is typically caused when the person experiences positive reinforcement for consuming the substance. Positive reinforcement is the experience of positive affect as a result of doing a specific act, each time the act is committed. The faster the drug produces the experience of positive reinforcement, the more addictive it can be. Addictive drugs typically cause an increase of dopamine in the nucleus accumbens. Some drugs do this by stimulating dopamine release by dopaminergic neurons in the mesolimbic system, and others do so by inhibiting the reuptake of dopamine by terminal buttons. PET studies with different drugs have provided evidence for these claims. Often, people also obtain negative reinforcement in the form of relief from adverse stimuli when they consume the said substance. Negative reinforcement entails the reduction of adverse experiences on committing an act. Addictive substances cause both these experiences to occur, and thus the person is motivated to continue to consume the substance.

Addiction is usually characterized by both tolerances to the substance and withdrawal. Tolerance is a reduced sensitivity to the substance with regular consumption. Thus, the person has to consume larger amounts of the substance to achieve the same experience. It is believed that tolerance occurs because the consumption of addictive substances affects the homeostatic mechanisms. This causes the body to produce the opposite effects to those caused by the drug in an attempt to re-create a balance. Thus, larger and larger doses are required to counter these changes and achieve a ‘high’. Withdrawal is the experience of symptoms that are the opposite of what the person experiences on consuming the substance in the event that they stop consuming it.&nbsp.Withdrawal is basically a state in which the changes in the brain functioning become evident once the effect of the drug has worn off.