Psychopharmacology (from Greek ψῡχή, psȳkhē, ‘breath, life, soul’; φάρμακον, pharmakon, ‘drug’; and -λογία, -logia) 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.