Psychopharmacology is the scientific study of the effects drugs have on mood, sensation, thinking, and behavior. It is distinguished from neuropsychopharmacology, which emphasizes the correlation between drug-induced changes in the functioning of cells in the nervous system and changes in consciousness and behavior. Psychiatric medication is a licensed psychoactive drug taken to exert an effect on the chemical makeup of the brain and nervous system. Thus, these medications are used to treat mental illnesses. Usually prescribed in psychiatric settings, these medications are typically made of synthetic chemical compounds. Since the mid-20th century, such medications have been leading treatments for a broad range of mental disorders and have decreased the need for long-term hospitalization, therefore lowering the cost of mental health care. The recidivism or rehospitalization of the mentally ill is at a high rate in many countries and the reasons for the relapses are under research. Peer review is the evaluation of work by one or more people with similar competencies as the producers of the work (peers). It functions as a form of self-regulation by qualified members of a profession within the relevant field. Peer review methods are used to maintain quality standards, improve performance, and provide credibility. In academia, scholarly peer review is often used to determine an academic paper's suitability for publication. Peer review can be categorized by the type of activity and by the field or profession in which the activity occurs, e.g., medical peer review.