Dully was born on November 30, 1948, in Oakland, California, the eldest son of Rodney and June Louise Pierce Dully. Following the death of his mother from cancer in 1954, Dully's father married single mother Shirley Lucille Hardin in 1955.
Neurologist Walter Freeman had diagnosed Dully as suffering from childhood schizophrenia since age 4, although numerous other medical and psychiatric professionals who had seen Dully did not detect a psychiatric disorder. In 1960, at 12 years of age, Dully was submitted by his father and stepmother for a trans-orbital lobotomy, performed by Freeman. During the procedure, a long, sharp instrument called a leucotome was inserted through each of Dully's eye sockets 7 cm (2.75 inches) into his brain.
Dully took decades to recover from the surgery to the point where he could function in society;[vague] he was institutionalized for years as a juvenile (in Agnews State Hospital as a minor), transferred to Rancho Linda School in San Jose, California, a school for children with behavior problems, incarcerated, and was eventually homeless and an alcoholic. After sobering up and getting a college degree in computer information systems, he became a California state certified behind-the-wheel instructor for a school bus company in San Jose, California.
In his 50s, with the assistance of National Public Radio producer David Isay, Dully started to research what had happened[why?] to him as a child, speaking with his family, relatives of other lobotomy patients, relatives of Dr. Freeman, and gaining access to Freeman's archives. Dully first related his story on a National Public Radio broadcast in 2005, prior to co-authoring a memoir published in 2007.