Once you get people to report a particular symptom, like 'I have a little trouble concentrating,' even if they would never say that on their own, you turn them into someone who later on says they do have trouble concentrating.' And it leaves them with a residual effect to keep doing so. 'One way is to give them misinformation about what they reported before, but this study shows yet another kind of suggestion, which is to induce people to, in essence, lie. 'This study shows a couple ways people come to believe they have troubles they wouldn't otherwise endorse,' says Elizabeth Loftus, a psychologist at the University of California, Irvine, renowned for her research on misinformation and false memories. The study has particularly serious implications for cases in which people fake mental illness to take advantage of the legal system.

Not only do the findings demonstrate that deliberately feigning illness can evolve into an unconscious embellishment of symptoms, they indicate that self-perception of mental health is susceptible to suggestion. People will also adopt and justify signs of illness that they never reported themselves when presented with manipulated answers, according to the study published online July 9 in the Journal of Clinical and Experimental Neuropsychology. People who fake symptoms of mental illness can convince themselves that they genuinely have those symptoms, a new study suggests.