Chang suffered a nervous breakdown in August 2004, which her family, friends, and doctors attributed in part to constant sleep deprivation, dozens of herbal supplements, and heavy doses of psychologically damaging prescription medication. At the time, she was several months into research for her fourth book, about the Bataan Death March. She was also promoting "The Chinese in America". While en route to Harrodsburg, Kentucky, where she planned to gain access to a "time capsule" of audio recordings from servicemen, she suffered an extreme bout of depression that left her unable to leave her hotel room in Louisville. A local veteran who was assisting her research helped her check into Norton Psychiatric Hospital in Louisville, where she was diagnosed with reactive psychosis, placed on heavy medication for three days and then released to her parents. After the release from the hospital, she continued to suffer from depression and experienced the side effects of several medications she was taking. Chang was also reportedly deeply disturbed by much of the subject matter of her research.