Why do people kill each other? It's a question most people ask when they hear someone has been killed. Sometimes a person kills another because part of their brain is not functioning properly; other times it's something much worse. (1: SV; SV.) Serial killers commit heinous crimes for several reasons: either the person suffers from a personality disorder or due to decreased connectivity in their brain. (3:SV:SV.) There isn't really a set definition of the term "serial killer." “The term 'serial murders' means a series of three or more murders, at least one of which was committed in the United States, having common characteristics such as to suggest the reasonable possibility that the crimes were committed by the person(s) same actors. .” (quoted by Robert J. Morton and Mark A. Hilts 5) At first, some psychologists thought it was a series of two to ten murders, each with a cooling-off period in between; this period of reflection is used to recover both the emotional and physical state of mind of the killer; its time period is also used to determine between a mass murder and a serial murder. (1c: SV; SV; SV.) This is the method used to determine the definition of "serial killer". The first signs of a serial killer can be detected at a young age. According to Shirley L. Scott, “Because serial killers only see others as objects, the jump from starting a fire to killing people is easy to make. » (Scott 5) This describes one of the signs, which sets fire just to destroy things. Another sign is bedwetting; Most psychologists believe it is a sign caused by the disturbing dreams of some potential serial killers. Another sign of a serial killer is harming animals. The...... middle of paper...... everyone around them; Serial killers commit these terrible crimes because of the connectivity of their brains or the way they are raised as children. (1b: SV; SV or SV.) The definition of the word "serial killer" is a series of three to ten murders, each with a rest period. Serial killers stay in the minds of many people for years, or even the rest of their lives. Works Cited Brogaard, Berit, DMSci, PhD and Kristian Marlow. “The Making of a Serial Killer.” Np, December 7, 2012. Web. October 29, 2013. “First signs of serial killers. » crimemuseum.org. National Crime and Punishment Museum. 2008. Internet. October 29, 2013. Ed. Robert J. Morton and Mark A. Hilts. “Serial murder”. FBI, nd Web. October 29, 2013. Pemment, Jack, MA “Blame the Amygdala.” Np, April 5, 2013. Web. October 29, 2013. Scott, Shirley L. “What Motivates Serial Killers?” » Crime Library, nd Web. November 21. 2013.