Researchers disagree over what exactly happens in the brain during self-deception. Social psychologists say people deceive themselves in an unconscious effort to boost self-esteem or feel better. Evolutionary psychologists, who say different parts of the brain can harbor conflicting beliefs at the same time, say self-deception is a way of fooling others to our own advantage.
In some people, the tendency seems to be an inborn personality trait. Others may develop a habit of self-deception as a way of coping with problems and challenges.
Behavioral scientists in recent years have begun using new techniques in the laboratory to predict when and why people are likely to deceive themselves. For example, they may give subjects opportunities to inflate their own attractiveness, skill or intelligence. Then, they manipulate such variables as subjects' mood, promises of rewards or opportunities to cheat. They measure how the prevalence of self-deception changes.
In an unpublished study earlier this year, young women were asked to stand in front of a sheet of brown paper and sketch outlines of their bodies. Some were then asked to read a story about dating to put them in a romantic mood. The others were asked to read about buildings and architecture, says Carrie Keating, a psychology professor at Colgate University
in Hamilton, N.Y., who led the research.
When the women were asked later to outline their bodies again, those who had read about dating sketched themselves as slimmer, with narrower waists, compared with their earlier drawings, reflecting an effort to "block out any negative information about their bodies" and succeed at the dating game, Dr. Keating says. The women who read about buildings didn't much change their sketches.
As early as age 3, children have what researchers call a "positivity bias"--a tendency to see themselves as smart regardless of their abilities, and to exaggerate positive traits in others, says a 2010 study in the journal Child Development Perspectives. By adolescence, one-fourth of college-bound students rate themselves in the top 1% in their ability to get along with others, research shows.
In a separate study, female students who take leadership positions on campus score higher on measures of self-deception, based on recent research by Dr. Keating. Women who aspire to leadership may have to "conveniently forget about some negatives," such as the fact that "women who behave in a dominant fashion may be perceived as more masculine," Dr. Keating says.
Many people have a way of "fooling their inner eye" to believe they are more successful or attractive than they really are, Dr. Trivers says. When people are asked to choose the most accurate photo of themselves from an array of images that are either accurate, or altered to make them look up to 50% more or less attractive, most choose the photo that looks 20% better than reality, research shows.
Many people deceive themselves to avoid making difficult changes.
Anything to avoid responsibility.