Whatever the cause, the bodily related distortions can recur several times a day and may take some time to abate. Understandably, the person can become alarmed, frightened, and panic-stricken throughout the course of the hallucinations—maybe even hurt themselves or others around them. The symptoms of the syndrome themselves are not harmful and are likely to disappear with time.

The psychological mechanism of conversion can be the most difficult aspect of a conversion diagnosis. Even if there is a clear antecedent trauma or other possible psychological trigger, it is still not clear exactly how this gives rise to the symptoms observed. Patients with medically unexplained neurological symptoms may not have any psychological stressor, hence the use of the term "functional neurological symptom disorder" in DSM-V as opposed to "conversion disorder", and DSM-V's removal of the need for a psychological trigger.

In the mental health field, schizophasia or word salad is language that is confused and often repetitious, symptomatic of various mental illnesses.

It is usually associated with a manic presentation of bipolar affective disorder and other symptoms of serious mental illnesses, such as psychosis, including schizophrenia. It is characterized by an apparently confused usage of words with no apparent meaning or relationship attached to them. In this context, it is considered to be a symptom of a formal thought disorder. In some cases schizophasia can be a sign of asymptomatic schizophrenia; e.g. the question "Why do people believe in God?" could elicit a response consisting of a series of words commonly associated with religion or prayer but strung together with no regard to language rules.

Schizophasia should be contrasted with another symptom of cognitive disruption and cognitive slippage involving certain idiosyncratic arrangements of words. With this symptom, the language may or may not be grammatically correct depending on the severity of the disease and the particular mechanisms which have been impacted by the disease.

The American diagnostic codes, from the "DSM-IV", do not specifically code for this disorder although they include it as a symptom under the diagnosis of schizophrenia.

Alice in Wonderland syndrome is a disturbance of perception rather than a specific physiological change to the body's systems. The diagnosis can be presumed when other causes have been ruled out and if the patient presents symptoms along with migraines and complains of onset during the day (although it can also occur at night).

Another symptom of Alice in Wonderland syndrome is sound distortion, such as every little movement making a clattering sound.

Treatment is dependent on the underlying cause, whether it is organic or psychological in origin. If depersonalization is a symptom of neurological disease, then diagnosis and treatment of the specific disease is the first approach. Depersonalization can be a cognitive symptom of such diseases as amyotrophic lateral sclerosis, Alzheimer's, multiple sclerosis (MS), neuroborreliosis (Lyme disease), or any other neurological disease affecting the brain. For those suffering from depersonalization with migraine, tricyclic antidepressants are often prescribed.

If depersonalization is a symptom of psychological causes such as developmental trauma, treatment depends on the diagnosis. In case of dissociative identity disorder or DD-NOS as a developmental disorder, in which extreme developmental trauma interferes with formation of a single cohesive identity, treatment requires proper psychotherapy, and—in the case of additional (co-morbid) disorders such as eating disorders—a team of specialists treating such an individual. It can also be a symptom of borderline personality disorder, which can be treated in the long term with proper psychotherapy and psychopharmacology.

The treatment of chronic depersonalization is considered in depersonalization disorder.

A recently completed study at Columbia University in New York City has shown positive effects from transcranial magnetic stimulation (TMS) to treat depersonalization disorder. Currently, however, the FDA has not approved TMS to treat DP.

A 2001 Russian study showed that naloxone, a drug used to reverse the intoxicating effects of opioid drugs, can successfully treat depersonalization disorder. According to the study: "In three of 14 patients, depersonalization symptoms disappeared entirely and seven patients showed a marked improvement. The therapeutic effect of naloxone provides evidence for the role of the endogenous opioid system in the pathogenesis of depersonalization."

Questionnaires and checklists such as the Beck Depression Inventory or the Children's Depression Inventory can be used by a mental health provider to help detect, and assess the severity of depression. The Seasonal Pattern Assessment Questionnaire can be used to screen for seasonal affective disorder. Semi structured interviews such as the Kiddie Schedule for Affective Disorders and Schizophrenia (KSADS) and the Structured Clinical Interview for DSM-IV (SCID) are used for diagnostic confirmation of depression.

Depersonalization is also a direct symptom of Lyme disease as well as other tick-borne diseases. If depersonalization is suspected a blood-test is required in search of anti-bodies.

Medical studies conclude that certain adjunctive drugs effectively palliate the negative symptoms of schizophrenia, mainly alogia. In one study, Maprotiline produced the greatest reduction in alogia symptoms with a 50% decrease in severity. Of the negative symptoms of schizophrenia, alogia had the second best responsiveness to the drugs, surpassed only by attention deficiency. D-amphetamine is another drug that has been tested on people with schizophrenia and found success in alleviating negative symptoms. This treatment, however, has not been developed greatly as it seems to have adverse effects on other aspects of schizophrenia such as increasing the severity of positive symptoms.

MAV is not recognized as a distinct diagnostic entity. Lembert and Neuhauser propose criteria for definite and probable migraine-associated vertigo.

A diagnosis of "definite migraine-associated vertigo" includes a case history of:

- episodic vestibular symptoms of at least moderate severity;

- current or previous history of migraine according to the 2004 "International Classification of Headache Disorders";

- one of the following migrainous symptoms during two or more attacks of vertigo: migrainous headache, photophobia, phonophobia, visual or other auras; and

- other causes ruled out by appropriate investigations.

A diagnosis of "probable migraine-associated vertigo" includes a case history of episodic vestibular symptoms of at least moderate severity and one of the following:

- current or previous history of migraine according to the 2004 "International Classification of Headache Disorders";

- migrainous symptoms during vestibular symptoms;

- migraine precipitants of vertigo in more than 50% of attacks, such as food triggers, sleep irregularities, or hormonal change;

- response to migraine medications in more than 50% of attacks; and

- other causes ruled out by appropriate investigations.

Note that, in both of the above criteria, headache is not required to make the diagnosis of migraine-associated vertigo.

They add that, in patients with a clear-cut history, no vestibular tests are required. Other historical criteria which are helpful in making the diagnosis of migraine-associated vertigo are vertiginous symptoms throughout the patient’s entire life, a long history of motion intolerance, sensitivity to environmental stimuli, illusions of motion of the environment, and vertigo that awakens the patient.

Symptoms can last for more than 4 weeks and typically resolve within a day of restoring the medication.

Treatment of migraine-associated vertigo is the same as the treatment for migraine in general.

BMS is a diagnosis of exclusion, i.e. all other explanations for the symptoms are ruled out before the diagnosis is made. There are no clinically useful investigations that would help to support a diagnosis of BMS (by definition all tests would have normal results), but blood tests and / or urinalysis may be useful to rule out anemia, deficiency states, hypothyroidism and diabetes. Investigation of a dry mouth symptom may involve sialometry, which objectively determines if there is any reduction of the salivary flow rate (hyposalivation). Oral candidiasis can be tested for with use of a swabs, smears, an oral rinse or saliva samples. It has been suggested that allergy testing ("e.g.", patch test) is inappropriate in the absence of a clear history and clinical signs in people with a burning sensation in the mouth. The diagnosis of a people with a burning symptom may also involve psychologic screening e.g. depression questionnaires.

The second edition of the International Classification of Headache Disorders lists diagnostic criteria for "Glossodynia and Sore Mouth":

Derealization (sometimes abbreviated as DR) is an alteration in the perception or experience of the external world so that it seems unreal. Other symptoms include feeling as though one's environment is lacking in spontaneity, emotional colouring, and depth. It is a dissociative symptom of many conditions.

Derealization is a subjective experience of unreality of the outside world, while depersonalization is sense of unreality in one's personal self, although most authors currently do not regard derealization (surroundings) and depersonalization (self) as separate constructs.

Chronic derealization may be caused by occipital–temporal dysfunction. These symptoms are common in the population, with a lifetime prevalence of up to 5% and 31–66% at the time of a traumatic event.

As it has already been mentioned, patients with organic personality disorder show a wide variety of sudden behavioural changes and dysfunctions. There are not a lot of information about the treatment of this mental health disorder. The pharmacological approach is the most common therapy among patients with organic personality disorder. However, the choice of drug therapy relies on the seriousness of patient's situation and what symptoms are shown. The choice and administration of specific drugs contribute to the reduction of symptoms of organic personality disorder. For this reason, it is crucial for patients' treatment to be assessed by clinical psychologists and psychiatrists before the administration of drug.

Additionally, the dysfunctions in expression of behaviour of patients with organic personality disorder and the development of symptom of irritability, which are caused by aggressive and self-injurious behaviours, can be dealt with the administration of carbamazepine. Moreover, the symptoms of this disorder can be decreased by the administration of valproic acid. Also, emotional irritability and signs of depression can be dealt with the use of nortriptyline and low-dose thioridazine. Except from the symptom of irritability, patients express aggressive behaviours. At the onset of drug therapy for effective treatment of anger and aggression, the drug of carbamazepine, phenobarbital, benztropine and haloperidol can be administrated in order to reduce the symptoms of patients with organic personality disorder. In addition, the use of propranolol may decrease the frequent behaviours of rage attacks.

Finally, it is important for patients to take part in psychotherapy sessions during the period of drug therapy. In this way, there is prevention and patients can be protected by negative effects of drugs on their organism and their behaviour. Furthermore, the clinicians can provide useful and helpful support to patients during these psychotherapy sessions. Thus, the combination of drug therapy with psychotherapy can lead to the reduction of symptoms of this disorder and the improvement of patients' situation.

Empirical studies have found that the prognosis for conversion disorder varies widely, with some cases resolving in weeks, and others enduring for years or decades. There is also evidence that there is no cure for Conversion Disorder, and that although patients may go into remission, they can relapse at any point. Furthermore, many patients who are 'cured' continue to have some degree of symptoms indefinitely.

In the opinion of Allen Frances, chair of the DSM-IV task force, the DSM-5's somatic symptom disorder brings with it a risk of mislabeling a sizable proportion of the population as mentally ill. “Millions of people could be mislabeled, with the burden falling disproportionately on women, because they are more likely to be casually dismissed as ‘catastrophizers’ when presenting with physical symptoms.”

A burning sensation in the mouth may be primary (i.e. burning mouth syndrome) or secondary to systemic or local factors. Other sources refer to a "secondary BMS" with a similar definition, i.e. a burning sensation which is caused by local or systemic factors, or "where oral burning is explained by a clinical abnormality". However this contradicts the accepted definition of BMS which specifies that no cause can be identified. "Secondary BMS" could therefore be considered a misnomer. BMS is an example of dysesthesia, or a distortion of sensation.

Some consider BMS to be a variant of atypical facial pain. More recently, BMS has been described as one of the 4 recognizable symptom complexes of chronic facial pain, along with atypical facial pain, temporomandibular joint dysfunction and atypical odontalgia. BMS has been subdivided into three general types, with type two being the most common and type three being the least common. Types one and two have unremitting symptoms, whereas type three may show remitting symptoms.

- Type 1 - Symptoms not present upon waking, and then increase throughout the day

- Type 2 - Symptoms upon waking and through the day

- Type 3 - No regular pattern of symptoms

Sometimes those terms specific to the tongue (e.g. "glossodynia") are reserved for when the burning sensation is located only on the tongue.

The ICD-10 includes a diagnostic guideline for the wide group of personality and behavioural disorders. However, every disorder has its own diagnostic criteria. In case of the organic personality disorder, patient has to show at least three of the following diagnostic criteria over a six or more months period. organic personality disorder is associated with a large variety of symptoms, such as deficits in cognitive function, dysfunctional behaviours, psychosis, neurosis, emotional changes, alterations in expression function and irritability. Patients with organic personality disorder can present emotional lability that means their emotional expressions are unstable and fluctuating. In addition, patients show reduction in ability of perseverance with their goals and they express disinhibited behaviours, which are characterised by inappropriate sexual and antisocial actions. For instance, patients can show dissocial behaviours, like stealing. Moreover, according to diagnostic guideline of ICD-10, patients can suffer from cognitive disturbances and they present signs of suspiciousness and paranoid ideas. Additionally, patients may present alteration in process of language production that means there are changes in language rate and flow. Furthermore, patients may show changes in their sexual preference and hyposexuality symptoms.

Another common feature of personality of patients with organic personality disorder is their dysfunctional and maladaptive behaviour that causes serious problems in these patients, because they face problems with pursuit and achievement of their goals. It is worth to be mentioned that patients with organic personality disorder express a feeling of unreasonable satisfaction and euphoria. Also, the patients show aggressive behaviours sometimes and these serious dysfunctions in their behaviour can have effects on their life and their relationships with other people. Specifically patients show intense signs of anger and aggression because of their inability to handle their impulses. The type of this aggression is called "impulsive aggression". Furthermore, it is worth to be mentioned that the pattern of organic personality disorder presents some similarities with pattern of temporal lobe epilepsy (TLE). Specifically patients who suffer from this chronic disorder type of epilepsy, express aggressive behaviours, likewise it happens to patients with organic personality disorder. Another similar symptom between Temporal lobe epilepsy and organic personality disorder is the epileptic seizure. The symptom of epileptic seizure has influence on patients' personality that means it causes behavioural alterations". The Temporal lobe epilepsy (TLE) is associated with the hyperexcitability of the medial temporal lobe (MTL) of patients. Finally, patients with organic personality disorder may present similar symptoms with patients, who suffer from the Huntington's disease as well. The symptoms of apathy and irritability are common between these two groups of patients.

Antidepressants, including SSRIs, can cross the placenta and have the potential to affect the fetus and newborns, presenting a dilemma whether pregnant women should take antidepressants at all, and if they do, whether tapering them near the end of pregnancy could have a protective effect for the newborn.

Postnatal adaptation syndrome (PNAS) (originally called “neonatal behavioral syndrome”, “poor neonatal adaptation syndrome”, or "neonatal withdrawal syndrome") was first noticed in 1973 in newborns of mothers taking antidepressants; symptoms in the infant include irritability, rapid breathing, hypothermia, and blood sugar problems. The symptoms usually develop from birth to days after delivery and usually resolve within days or weeks of delivery.

Tangentiality as a medical symptom is a physical symptom observed in speech that tends to occur in situations where a person is experiencing high anxiety, as a manifestation of the psychosis known as "schizophrenia", in dementia or in states of delirium.

Derealization can accompany the neurological conditions of epilepsy (particularly temporal lobe epilepsy), migraine, and mild head injury. There is a similarity between visual hypo-emotionality, a reduced emotional response to viewed objects, and derealization. This suggests a disruption of the process by which perception becomes emotionally coloured. This qualitative change in the experiencing of perception may lead to reports of anything viewed being unreal or detached.

Derealization can also manifest as an indirect result of certain vestibular disorders such as labyrinthitis. This is thought to result from the experience of anxiety precipitated by the functional disparity that arises between the ability to reconcile external stimuli relative to motion and equilibrioception that are compromised by vestibular dysfunction with the internal perceptions and expectations regarding the physical environment.

An alternative explanation holds that a possible effect of vestibular dysfunction includes responses in the form of the modulation of noradrenergic and serotonergic activity due to a misattribution of vestibular symptoms to the presence of imminent physical danger resulting in the experience of anxiety or panic, which subsequently generate feelings of derealization.

Cannabis, psychedelics, dissociatives, antidepressants, caffeine, nitrous oxide, albuterol, and nicotine can all produce feelings resembling derealization, particularly when taken in excess. It can result from alcohol withdrawal or benzodiazepine withdrawal. Opiate withdrawal can also cause feelings of derealization.

Derealization can also be a symptom of severe sleep disorders and mental disorders like depersonalization disorder, borderline personality disorder, bipolar disorder, schizophrenia, dissociative identity disorder, and anxiety disorders.

Interoceptive exposure can be used as a means to induce derealization, as well as the related phenomenon depersonalization.

According to the St. Louis system for the diagnosis of schizophrenia, tangentiality is significantly associated with a low IQ prior to diagnosis (AU Parnas "et al" 2007).

Depressed mood may not require professional treatment, and may be a normal temporary reaction to life events, a symptom of some medical condition, or a side effect of some drugs or medical treatments. A prolonged depressed mood, especially in combination with other symptoms, may lead to a diagnosis of a psychiatric or medical condition which may benefit from treatment. Different sub-divisions of depression have different treatment approaches.

In the United States, it has been estimated that two thirds of people with depression do not actively seek treatment. The World Health Organisation (WHO) has predicted that by 2030, depression will account for the highest level of disability accorded any physical or mental disorder in the world (WHO, 2008).

The UK National Institute for Health and Care Excellence (NICE) 2009 guidelines indicate that antidepressants should not be routinely used for the initial treatment of mild depression, because the risk-benefit ratio is poor. A recent meta-analysis also indicated that most antidepressants, besides fluoxetine, do not seem to offer a clear advantage for children and adolescents in the acute treatment of major depressive disorder.

Somatic symptom disorder has been a controversial diagnosis, since it was historically based primarily on negative criteria - that is, the absence of a medical explanation for the presenting physical complaints. Consequently, any person suffering from a poorly understood illness can potentially fulfill the criteria for this psychiatric diagnosis, even if they exhibit no psychiatric symptoms in the conventional sense. In 2013-4, there were several widely publicized cases of individuals being involuntarily admitted to psychiatric wards on the basis of this diagnosis alone. This has raised concerns about the consequences of potential misuse of this diagnostic category.

Although medication is the first-line treatment for most psychiatric disorders, it does not always improve every aspect of a patient's life, and for the negative symptoms in schizophrenia, the responses to anti-psychotics are less favourable than for positive symptoms. As a result, psychotherapy might be an alternative for the treatment of these symptoms, even if medication has a good effect on other manifestations of the disorder.

Cognitive behavioural therapy (CBT), is the kind of psychotherapy that shows most promise in treating avolition (and other negative symptoms of schizophrenia), but more research is needed in the area. CBT focuses on understanding how thoughts and feelings influence behaviour, in order to help individuals develop methods and strategies to better handle the implications of their disorder. Some research suggests that CBT focusing on social skills and practice of interpersonal situations, like job interviews, seeing a doctor (to discuss medication, for example), or interacting with friends and co-workers, as well as seemingly simple things like riding a bus, might reduce negative symptoms of schizophrenia and be beneficial to patients with avolition.

Other forms of psychotherapy might also complement the role of medication and help patients, their families, and friends to work through emotional and other challenges of living with a chronic psychological disorder, including avolition.