Although many studies have searched for the underpinnings of personality since the completion of the Human Genome Project, in 2003, many of the relevant genes remain in question.
For many years before his paper on reparative therapy, Spitzer had conducted studies that evaluated the efficacy of self-reporting as a tool to assess a variety of personality disorders and depression.
The desire to fly an airplane has been shown to represent one aspect of a sensation-seeking personality, a genetic trait associated with risky behavior involving driving, sex, sports and vocation, according to psychology studies.