After recovery from a fugue state, previous memories usually return intact, and further treatment is unnecessary. Additionally, an episode of fugue is not characterized as attributable to a psychiatric disorder if it can be related to the ingestion of psychotropic substances, to physical trauma, to a general medical condition, or to dissociative identity disorder,[clarification needed]delirium, or dementia. Fugues are precipitated by a series of long-term traumatic episodes. It is most commonly associated with childhood victims of sexual abuse who learn over time to dissociate memory of the abuse (dissociative amnesia).
Symptoms of a dissociative fugue include mild confusion, and once the fugue ends, possible depression, grief, shame and discomfort. People have also experienced a post-fugue anger.
A doctor may suspect dissociative fugue when people seem confused about their identity or are puzzled about their past or when confrontations challenge their new identity or absence of one. The doctor carefully reviews symptoms and does a physical examination to exclude physical disorders that may contribute to or cause memory loss.
Sometimes dissociative fugue cannot be diagnosed until people abruptly return to their pre-fugue identity and are distressed to find themselves in unfamiliar circumstances. The diagnosis is usually made retroactively when a doctor reviews the history and collects information that documents the circumstances before people left home, the travel itself, and the establishment of an alternative life.
Functional amnesia can also be situation specific, varying from all forms and variations of traumas or generally violent experiences, with the person experiencing severe memory loss for a particular trauma. Committing homicide; experiencing or committing a violent crime such as rape or torture; experiencing combat violence; attempting suicide; and being in automobile accidents and natural disasters have all induced cases of situation-specific amnesia (Arrigo & Pezdek, 1997; Kopelman, 2002a). As Kopelman (2002a) notes, however, care must be exercised in interpreting cases of psychogenic amnesia when there are compelling motives to feign memory deficits for legal or financial reasons. However, although some fraction of psychogenic amnesia cases can be explained in this fashion, it is generally acknowledged that true cases are not uncommon. Both global and situationally specific amnesia are often distinguished from the organic amnesic syndrome, in that the capacity to store new memories and experiences remains intact. Given the very delicate and often times dramatic nature of memory loss in these such cases, there usually is a concerted effort to help the person recover their identity and history. This will allow the subject to sometimes be recovered spontaneously when particular cures are encountered.
The cause of the fugue state is related to dissociative amnesia, (DSM-IV Codes 300.12) which has several other subtypes: selective amnesia, generalised amnesia, continuous amnesia, and systematised amnesia, in addition to the subtype dissociative fugue.
Unlike retrograde amnesia (which is popularly referred to simply as "amnesia", the state where someone forgets events before brain damage), dissociative amnesia is not due to the direct physiological effects of a substance (e.g., a drug of abuse, a medication, DSM-IV Codes 291.1 & 292.83) or a neurological or other general medical condition (e.g., amnestic disorder due to a head trauma, DSM-IV Codes 294.0). It is a complex neuropsychological process.
As the person experiencing a dissociative fugue may have recently suffered the reappearance of an event or person representing an earlier life trauma, the emergence of an armoring or defensive personality seems to be for some, a logical apprehension of the situation.
Therefore, the terminology fugue state may carry a slight linguistic distinction from dissociative fugue, the former implying a greater degree of motion. For the purposes of this article then, a fugue state occurs while one is acting out a dissociative fugue.
One or more episodes of amnesia in which the inability to recall some or all of one's past and either the loss of one's identity or the formation of a new identity occur with sudden, unexpected, purposeful travel away from home.
In support of this definition, the Merck Manual further defines dissociative amnesia as:
An inability to recall important personal information, usually of a traumatic or stressful nature, that is too extensive to be explained by normal forgetfulness.
The DSM-IV-TR states that the fugue may have a duration from days to months, and recovery is usually rapid. However, some cases may be refractory. An individual usually has only one episode.
Jody Roberts, a reporter for the Tacoma News Tribune, disappeared in 1985, only to be found 12 years later in Sitka, Alaska, living under the name of "Jane Dee Williams." While there were some initial suspicions that she had been faking amnesia, some experts have come to believe that she genuinely experienced a protracted fugue state.
David Fitzpatrick, who had dissociative fugue disorder, was profiled on Five's television series Extraordinary People. He entered a fugue state on December 4, 2005, and is still working on regaining his entire life's memories.
Hannah Upp, a teacher originally from Salem, Oregon, was given a diagnosis of dissociative fugue after she had disappeared from her New York home in August 2008 and was rescued from the New York Harbor 20 days later. News coverage at the time focused on her refusal to speak to detectives right after she was found  and that she was seen checking her email at Apple Stores while she was missing,. This coverage has since led to criticism of the often "condemning and discrediting" attitude towards disassociative conditions. On September 3, 2013, she went into another fugue, disappearing from her new job as a teacher's assistant at Crossway Community Montessori in Kensington, Maryland. She was found unharmed September 5, 2013 in Wheaton, Maryland. As of September 14, 2017, she is missing again; she was last seen near Sapphire Beach in her home in St. Thomas right before Hurricane Maria. Her mother and a group of friends are currently searching for her in the Virgin Islands and surrounding areas.
Jeff Ingram appeared in Denver in 2006 with no memory of his name or where he was from. After his appearance on national television, to appeal for help identifying himself, his fiancée Penny called Denver police identifying him. The episode was diagnosed as dissociative fugue. Ingram has experienced three incidents of amnesia: in 1994, 2006, and 2007.
Doug Bruce "came to" on a subway train claiming to have no memory of his name or where he was from, nor any identification documents.
AMN, a 23-year-old insurance worker. AMN discovered a small fire in the basement of his house and left to call for help. On his escape he did not inhale any smoke, and he smashed the cellar door open then immediately ran out of the house. That evening, he appeared dazed and frightened, and the next morning when he awoke, he no longer knew what his profession was nor even where he lived. Approximately three weeks went by and he finally checked himself into a hospital, where AMN was examined by medical professionals. It became clear that his memories extended only until the age of 17. He barely recognized his partner, whom he had known for three years, and he did not recognize his friends or coworkers. AMN immediately underwent therapy. Three weeks later, he reported one of his earliest memories as a child. At the age of four, he saw a car crash, which set another car on fire. He was then witness to the driver’s screams and his agonizing death in the flames, with his head pressed against the window. Since that time, fire had been AMN’s worst fear. Despite the horror, AMN showed normal psychological and physical development and throughout his life showed next to no evidence of psychological illness. A full examination revealed no obvious evidence of any sort of brain damage, although there were signs of greatly reduced metabolism present in memory-related areas. Eight months later, at the time of the report, AMN’s deficits in personal memory remained. It can be observed in the case of AMN that a particular event makes contact with a trauma and triggers a massive reaction. The stressful event can cause a profound loss of personal memory for public events and general knowledge is often intact. Unlike in AMN’s case, amnesia can be global, affecting the entirety of a person’s history.