In an unusual study conducted by a team of psychiatrists and literary scholars, the Harvard group was unable to uncover any examples of the phenomenon in Western writings that are more than 200 years old, The Washington Post reported.
Study leader Harrison Pope of Harvard Medical School says dissociative amnesia or repressed memory first appears in 19th-century literature such as the poetry of Emily Dickinson.
The group theorizes that if the disorder were anything other than a culture-bound syndrome, there would be examples of it in earlier literature because art draws its inspiration from life.
They point out that Shakespeare and Homer created numerous characters suffering from psychiatric disorders like schizophrenia or depression but none exhibiting repressed memory, the Post reported.
Writing in the journal Psychological Medicine, the researchers are offering $1,000 to anyone who can produce an example to disprove their theory that repressed memory is a cultural creation.