Parker and colleagues used a variety of standardised neuropsychological tests in their diagnosis of AJ's hyperthymesia. These included tests of memory, lateralisation, executive functions, language, calculations, IQ, and visual-spatial and visual-motor functions. They also devised novel tests to examine the extent of her memory abilities. These mostly consisted of questions pertaining to specific dates and events in history. Some of her personal recollections were verified with diary entries, as well as by her mother.

More recently, neuroscientist David Eagleman at Baylor College of Medicine developed a free on-line test for hyperthymesia. Participants first give their year of birth, and then are challenged to match dates to 60 famous events that happened between the time they were five years old and the present day. To qualify as potentially hyperthymestic, participants must achieve a score at least three standard deviations above the average. To prevent people from searching for answers on-line during the test, reaction time for each question is measured; answers must be chosen within 11 seconds to qualify for consideration. However, many of the questions are sourced in American culture and test results could have a strong cultural bias against non-Americans.

Before the development of the current tests for the assessment of post-traumatic amnesia (PTA), a retrospective method was used to determine the patient's condition, consisting of one or more interviews with the patient after the episode of PTA was judged to be over. The retrospective method, however, fails to account for the apparent lucidity of patients who are still experiencing substantial disorientation, or the finding that the recovery from post-traumatic amnesia is often characterized by the presence of "islands of memory" (short periods of clarity). A failure to take these facts into consideration may have biased retrospective methods towards underestimating the length and severity of an episode of PTA. Also, the retrospective method relies on retrospective memory, one's memory for past events, which is not very reliable in healthy individuals, and even less so in patients who have recently experienced a traumatic brain injury (TBI). Patients may also unconsciously or consciously bias their answers because they want to appear more healthy or more ill than they truly were, or because of poor insight. The retrospective method is also flawed because there is no standard measurement procedure. Although the retrospective method may provide useful subjective data, it is not a useful tool for measurement or categorization.

Although the GOAT has proved useful in acute care, recent research has called attention to some of its drawbacks. The GOAT's assessment of orientation may put too much of a focus on memory as the main mechanism behind orientation. The range of cognitive and behavioral symptoms associated with PTA seems to indicate that the patient's disorientation is more than just a memory deficit. Consequently, it may be beneficial to incorporate tests of other cognitive functions, such as attention, which relate to both memory and orientation.

Another recent study compared the success of the GOAT and the Orientation Log (O-Log) in predicting rehabilitation outcomes, and found that, while the O-Log and the GOAT perform similarly as measures of PTA severity and duration, the O-Log provides a more accurate picture of rehabilitation.

While the GOAT is a useful tool, these results suggest that using alternative methods of assessing PTA may increase the amount of information available to physicians and may help in predicting rehabilitative success. The international cognitive (INCOG) expert panel has recommended the use of a validated PTA scale such as the GOAT or WPTAS for assessing PTA duration in patients with moderate-to-severe traumatic brain injury on a daily basis.

The Gudjonsson Compliance Scale is a self-report instrument that measures peoples' levels of compliance. It focuses on two types of behavior, namely eagerness to please others, and avoidance of conflicts. The scale consists of 20 items using

a true/false format. Examples are 'I give in easily to people when I am pressured' and 'I try hard to do what is expected of me'. After recoding items 17 to 19, a total GCS score varying from 0 to 20 can be obtained by summing the number of true responses, with higher scores indexing more compliant behavior.

Confabulations can also be detected using a free recall task, such as a self-narrative task. Participants are asked to recall stories (semantic or autobiographical) that are highly familiar to them. The stories recalled are encoded for errors that could be classified as distortions in memory. Distortions could include falsifying true story elements or including details from a completely different story. Errors such as these would be indicative of confabulations.

Confabulations can also be researched by using continuous recognition tasks. These tasks are often used in conjunction with confidence ratings. Generally, in a recognition task, participants are rapidly presented with pictures. Some of these pictures are shown once; others are shown multiple times. Participants press a key if they have seen the picture previously. Following a period of time, participants repeat the task. More errors on the second task, versus the first, are indicative of confusion, representing false memories.

The Gudjonsson suggestibility scale (GSS) is used to measure interrogative suggestibility. The GSS consists of a story that is read out loud by a test administer. Participants then have to answer 20 questions of which 15 are misleading and 5 are neutral and address factual details of the story. After participants have answered the questions, they receive negative feedback about their performance. They are asked to answer the questions one more time and to be more accurate this time. Thus, all questions are answered twice and in this way several GSS parameters can be calculated. First, yield 1 refers to the number of misleading questions that the participant accepts during the first round (range 0–15). Second, yield 2 refers to the number of misleading questions accepted during the second round (range 0–15). Third, shift refers to the number of changes that participants make in their answers after having received negative feedback (range 0–20). Finally, the total GSS score is the sum of yield 1 and shift, with higher scores reflecting higher levels of interrogative suggestibility (range 0–35).

Assessment of patients with DES can be difficult because traditional tests generally focus on one specific problem for a short period of time. People with DES can do fairly well on these tests because their problems are related to integrating individual skills into everyday tasks. The lack of everyday application of traditional tests is known as low ecological validity.

Hyperthymesia is the condition of possessing an extremely detailed autobiographical memory. People with hyperthymesia remember an abnormally vast number of their life experiences.

American neurobiologists Elizabeth Parker, Larry Cahill, and James McGaugh (2006) identified two defining characteristics of hyperthymesia: spending an excessive amount of time thinking about one's past, and displaying an extraordinary ability to recall specific events from one's past. The word "hyperthymesia" derives from Ancient Greek: "hyper-" ("excessive") and "thymesis" ("remembering").

Clinically, anosognosia is often assessed by giving patients an anosognosia questionnaire in order to assess their metacognitive knowledge of deficits. However, neither of the existing questionnaires applied in the clinics are designed thoroughly for evaluating the multidimensional nature of this clinical phenomenon; nor are the responses obtained via offline questionnaire capable of revealing the discrepancy of awareness observed from their online task performance. The discrepancy is noticed when patients showed no awareness of their deficits from the offline responses to the questionnaire but demonstrated reluctance or verbal circumlocution when asked to perform an online task. For example, patients with anosognosia for hemiplegia may find excuses not to perform a bimanual task even though they do not admit it is because of their paralyzed arms.

A similar situation can happen on patients with anosognosia for cognitive deficits after traumatic brain injury when monitoring their errors during the tasks regarding their memory and attention (online emergent awareness) and when predicting their performance right before the same tasks (online anticipatory awareness). It can also occur among patients with dementia and anosognosia for memory deficit when prompted with dementia-related words, showing possible pre-attentive processing and implicit knowledge of their memory problems. More interestingly, patients with anosognosia may overestimate their performance when asked in first-person formed questions but not from a third-person perspective when the questions referring to others.

When assessing the causes of anosognosia within stroke patients, CT scans have been used to assess where the greatest amount of damage is found within the various areas of the brain. Stroke patients with mild and severe levels of anosognosia (determined by response to an anosognosia questionnaire) have been linked to lesions within the temporoparietal and thalamic regions, when compared to those who experience moderate anosognosia, or none at all. In contrast, after a stroke, people with moderate anosognosia have a higher frequency of lesions involving the basal ganglia, compared to those with mild or severe anosognosia.

Functional assessment of brain activity can be assessed for psychogenic amnesia using imaging techniques such as fMRI, PET and EEG, in accordance with clinical data. Some research has suggested that organic and psychogenic amnesia to some extent share the involvement of the same structures of the temporo-frontal region in the brain. It has been suggested that deficits in episodic memory may be attributable to dysfunction in the limbic system, while self-identity deficits have been suggested as attributable to functional changes related to the posterior parietal cortex. To reiterate however, care must be taken when attempting to define causation as only "ad hoc" reasoning about the aetiology of psychogenic amnesia is possible, which means cause and consequence can be infeasible to untangle.

The Behavioural Assessment of the Dysexecutive Syndrome (BADS) was designed to address the problems of traditional tests and evaluate the everyday problems arising from DES. BADS is designed around six subtests and ends with the Dysexecutive Questionnaire (DEX). These tests assess executive functioning in more complex, real-life situations, which improves their ability to predict day-to-day difficulties of DES.

The Dysexecutive Questionnaire (DEX) is a 20-item questionnaire designed to sample emotional, motivational, behavioural and cognitive changes in a subject with DES. One version is designed for the subject to complete and another version is designed for someone who is close to the individual, such as a relative or caregiver. Instructions are given to the participant to read 20 statements describing common problems of everyday life and to rate them according to their personal experience. Each item is scored on a 5-point scale according to its frequency from "never" (0 point) to "very often" (4 points).

Clinically induced RA has been achieved using different forms of electrical induction.

- Electroconvulsive therapy (ECT), used as a depression therapy, can cause impairments in memory. Tests show that information of days and weeks before the ECT can be permanently lost. The results of this study also show that severity of RA is more extreme in cases of bilateral ECT rather than unilateral ECT. Impairments can also be more intense if ECT is administered repetitively (sine wave simulation) as opposed to a single pulse (brief-pulse stimulation).

- Electroconvulsive shock (ECS): The research in this field has been advanced by using animals as subjects. Researchers induce RA in rats, for example, by giving daily ECS treatments. This is done to further understand RA.

As previously mentioned, RA can affect people's memories in different degrees, but testing is required to help determine if someone is experiencing RA. Several tests exist, for example, testing for factual knowledge such as known public events. A problem with this form of testing is that people generally differ in their knowledge of such subjects. Other ways to test someone is via autobiographical knowledge using the Autobiographical Memory Interview (AMI), comprising names of relatives, personal information, and job history. This information could help determine if someone is experiencing RA and the degree of memory affected. However, due to the nature of the information being tested, it is often difficult to verify the accuracy of the memories being recalled, especially if they are from a distant past. Some researchers have found that the time interval after the head injury occurred did not seem to matter. The effect of the memory loss was the same no matter how long it had been after from the injury.

Brain abnormalities can be measured using magnetic resonance imaging (MRI), computed tomography scan (CT) and electroencephalography (EEG), which can provide detailed information about specific brain structures. In many cases, an autopsy helps identify the exact brain region affected and the extent of the damage that caused RA once the patient has died.

There are some aspects essential to the patient that remain unaffected by RA. In many patients, their personality remains the same. Also, semantic memory, that is general knowledge about the world, is usually unaffected. However, episodic memory, which refers to one's life experiences, is impaired.

Another real life problem with RA is malingering, which is conceived as the rational output of a neurologically normal brain aiming at the surreptitious achievement of a well identified gain. Since it is common for people who have committed a crime to report having RA for that specific event in order to avoid their punishment, the legal system has pushed for the creation of a standardized test of amnesia. However, since most cases differ in onset, duration, and content forgotten, this task has shown to be a rather complex one.

In regard to anosognosia for neurological patients, no long-term treatments exist. As with unilateral neglect, caloric reflex testing (squirting ice cold water into the left ear) is known to temporarily ameliorate unawareness of impairment. It is not entirely clear how this works, although it is thought that the unconscious shift of attention or focus caused by the intense stimulation of the vestibular system temporarily influences awareness. Most cases of anosognosia appear to simply disappear over time, while other cases can last indefinitely. Normally, long-term cases are treated with cognitive therapy to train patients to adjust for their inoperable limbs (though it is believed that these patients still are not "aware" of their disability). Another commonly used method is the use of feedback – comparing clients' self-predicted performance with their actual performance on a task in an attempt to improve insight.

Neurorehabilitation is difficult because, as anosognosia impairs the patient's desire to seek medical aid, it may also impair their ability to seek rehabilitation. A lack of awareness of the deficit makes cooperative, mindful work with a therapist difficult. In the acute phase, very little can be done to improve their awareness, but during this time, it is important for the therapist to build a therapeutic alliance with patients by entering their phenomenological field and reducing their frustration and confusion. Since severity changes over time, no single method of treatment or rehabilitation has emerged or will likely emerge.

In regard to psychiatric patients, empirical studies verify that, for individuals with severe mental illnesses, lack of awareness of illness is significantly associated with both medication non-compliance and re-hospitalization. Fifteen percent of individuals with severe mental illnesses who refuse to take medication voluntarily under any circumstances may require some form of coercion to remain compliant because of anosognosia. Coercive psychiatric treatment is a delicate and complex legal and ethical issue.

One study of voluntary and involuntary inpatients confirmed that committed patients require coercive treatment because they fail to recognize their need for care. The patients committed to the hospital had significantly lower measures of insight than the voluntary patients.

Anosognosia is also closely related to other cognitive dysfunctions that may impair the capacity of an individual to continuously participate in treatment. Other research has suggested that attitudes toward treatment can improve after involuntary treatment and that previously committed patients tend later to seek voluntary treatment.

Diagnosis of Wernicke–Korsakoff syndrome is by clinical impression and can sometimes be confirmed by a formal neuropsychological assessment. Wernicke's encephalopathy typically presents with ataxia and nystagmus, and Korsakoff's psychosis with anterograde and retrograde amnesia and confabulation upon relevant lines of questioning.

Frequently, secondary to thiamine deficiency and subsequent cytotoxic edema in Wernicke's encephalopathy, patients will have marked degeneration of the mamillary bodies. Thiamine (vitamin B) is an essential coenzyme in carbohydrate metabolism and is also a regulator of osmotic gradient. Its deficiency may cause swelling of the intracellular space and local disruption of the blood-brain barrier. Brain tissue is very sensitive to changes in electrolytes and pressure and edema can be cytotoxic. In Wernicke's this occurs specifically in the mammillary bodies, medial thalami, tectal plate, and periaqueductal areas. Sufferers may also exhibit a dislike for sunlight and so may wish to stay indoors with the lights off. The mechanism of this degeneration is unknown, but it supports the current neurological theory that the mammillary bodies play a role in various "memory circuits" within the brain. An example of a memory circuit is the Papez circuit.

There have been assertions of a possible link between TGA and the use of statins (a class of drug used in treating cholesterol).

En bloc memory loss which is total, permanent, and irrecoverable can occur as an alcoholic "black out," usually lasting longer than an hour and up to 2–5 days.

Marijuana intoxication, Halogenated hydroxyquinolines such as Clioquinol, PDE inhibitors such as sildenafil, Digitalis and scopolamine intoxication, and general anaesthesia have been reported with TGA.

Because psychogenic amnesia is defined by its lack of physical damage to the brain, treatment by physical methods is difficult. Nonetheless, distinguishing between organic and dissociative memory loss has been described as an essential first-step in effective treatments. Treatments in the past have attempted to alleve psychogenic amnesia by treating the mind itself, as guided by theories which range from notions such as 'betrayal theory' to account for memory loss attributed to protracted abuse by caregivers to the amnesia as a form of self-punishment in a Freudian sense, with the obliteration of personal identity as an alternative to suicide.

Treatment attempts often have revolved around trying to discover what traumatic event had caused the amnesia, and drugs such as intravenously administered barbiturates (often thought of as 'truth serum') were popular as treatment for psychogenic amnesia during World War II; benzodiazepines may have been substituted later. 'Truth serum' drugs were thought to work by making a painful memory more tolerable when expressed through relieving the strength of an emotion attached to a memory. Under the influence of these 'truth' drugs the patient would more readily talk about what had occurred to them. However, information elicited from patients under the influence of drugs such as barbiturates would be a mixture of truth and fantasy, and was thus not regarded as scientific in gathering accurate evidence for past events. Often treatment was aimed at treating the patient as a whole, and probably varied in practice in different places. Hypnosis was also popular as a means for gaining information from people about their past experiences, but like 'truth' drugs really only served to lower the threshold of suggestibility so that the patient would speak easily but not necessarily truthfully. If no motive for the amnesia was immediately apparent, deeper motives were usually sought by questioning the patient more intensely, often in conjunction with hypnosis and 'truth' drugs. In many cases, however, patients were found to spontaneously recover from their amnesia on their own accord so no treatment was required.

CT scan or MRI can confirm dementia via observation of ventricular dilation and cortical substance degeneration.

Pick's disease can be confirmed via CT scan or MRI with atrophy of frontal and temporal lobe roots.

Alzheimer's is a disease confirmed by atrophy of the parietal and temporal lobe ganglia along with changes in the cortical ganglia found in a CT scan or MRI.

Serotonin and norepinephrine reuptake inhibitor, venlafaxine, were given to case study KS four months after initial stroke that started symptoms of witzelsucht. Changes back to his original behavior were noticeable after daily dose of 37.5 mg of venlafaxine for two weeks. In subsequent two months, inappropriate jokes and hypersexual behavior were rarely noticed. Due to the rareness of this disorder, not much research into potential treatments has been conducted.

Along with occupational and environmental evaluation, a neurological exam, ECHO, EEG, CT-San, and X-ray of the brain may be conducted to determine disorder. Neuroimaging that detects cerebral atrophy or cardiovascular subcortical alterations can help point to psychoorganic syndrome. Strong CNS lesions are detected in POS patients. However, this is found to be difficult as many psychiatric disorders, like dementia, have common diagnosis.

Diagnosing POS is an ongoing and developing in the medical and psychiatric industry. Exact diagnosis is difficult due to many symptoms mirroring other psychological disorders in the older aged patients.

Once it has been positively identified, pharmacotherapy follows. Antipsychotic drugs are the frontrunners in treatment for Fregoli and other DMSs. In addition to antipsychotics, anticonvulsants and antidepressants are also prescribed in some treatment courses. If a Fregoli patient has other psychological disorders, treatment often results in the use of trifluoperazine.

Approaches used to treat those who suffer from anterograde amnesia often use interventions which focus on compensatory techniques, such as beepers, written notes, diaries or through intensive training programs involving the active participation of the individual concerned, along with their supporting network of family and friends.

In this perspective, environmental adaptation techniques are used, such as the compensatory technique education to training (exercise), organizational strategies, visual imagery and verbal labeling. In addition, other techniques are also used in rehabilitation, such as implicit tasks, speech and mnemotechnic methods.

So far, it has been proven that education techniques of compensatory strategies for memory disorders are effective in individuals with minor traumatic brain injuries. In moderately or severely injured individuals, effective interventions are those appealing to external aids, such as reminders in order to facilitate particular knowledge or skill acquisition. Reality orientation techniques are also considered; Their purpose is to enhance orientation using stimulation and repetition of the basic orientation information. These techniques are regularly applied in populations of patients primarily presenting with dementia and head-injured patients.

When there is damage to just one side of the MTL, there is opportunity for normal functioning or near-normal function for memories. Neuroplasticity describes the ability of the cortex to remap when necessary. Remapping can occur in cases like the one above, and, with time, the patient can recover and become more skilled at remembering. A case report describing a patient who had two lobectomies – in the first, doctors removed part of her right MTL first because of seizures originating from the region, and later her left because she developed a tumor – demonstrates this. This case is unique because it is the only one in which both sides of the MTL were removed at different times. The authors observed that the patient was able to recover some ability to learn when she had only one MTL, but observed the deterioration of function when both sides of the MTL were afflicted. The reorganization of brain function for epileptic patients has not been investigated much, but imaging results show that it is likely.

The prognosis of "pure" TGA is very good. It does not affect mortality or morbidity and unlike earlier understanding of the condition, TGA is not a risk factor for stroke or ischemic disease. Rates of recurrence are variously reported, with one systematic calculation suggesting the rate is under 6% per year. TGA "is universally felt to be a benign condition which requires no further treatment other than reassurance to the patient and his or her family."

"The most important part of management after diagnosis is looking after the psychological needs of the patient and his or her relatives. Seeing a once competent and healthy partner, sibling or parent become incapable of remembering what was said only a minute ago is very distressing, and hence it is often the relatives who will require reassurance."

TGA may have multiple etiologies and prognoses. Atypical presentations may masquerade as epilepsy and be more properly considered TEA. In addition to such probable TEA cases, some people experiencing amnestic events diverging from the diagnostic criteria articulated above may have a less benign prognosis than those with "pure" TGA.

Recently, moreover, both imaging and neurocognitive testing studies question whether TGA is as benign as has been thought. MRI scans of the brain in one study showed that among people who had experienced TGA, all had cavities in the hippocampus, and these cavities were far more numerous, larger, and more suggestive of pathological damage than in either healthy controls or a large control group of people with tumor or stroke. Verbal and cognitive impairments have been observed days after TGA attacks, of such severity that the researchers estimated the effects would be unlikely to resolve within a short time frame. A large neurocognitive study of patients more than a year after their attack has shown persistent effects consistent with amnestic mild cognitive impairment (MCI-a) in a third of the people who had experienced TGA. In another study, "selective cognitive dysfunctions after the clinical recovery" were observed, suggesting a prefrontal impairment. These dysfunctions may not be in memory "per se" but in retrieval, in which speed of access is part of the problem among people who have had TGA and experience ongoing memory problems.