Ataque de nervios was first mentioned in Puerto Rico by US military psychiatrists who observed a young Puerto Rican experiencing unusual illness.

Reported aspects of the syndrome include uncontrollable screaming or shouting, crying, trembling, sensations of heat rising in the chest and head, dissociative experiences, and verbal or physical aggression. The reaction is usually associated with a stressful event relating to the family, although it is not specifically defined as arising from such occurrences.

In medicine and medical anthropology, a culture-bound syndrome, culture-specific syndrome, or folk illness is a combination of psychiatric and somatic symptoms that are considered to be a recognizable disease only within a specific society or culture. There are no objective biochemical or structural alterations of body organs or functions, and the disease is not recognized in other cultures. The term "culture-bound syndrome" was included in the fourth version of the "Diagnostic and Statistical Manual of Mental Disorders" (American Psychiatric Association, 1994) which also includes a list of the most common culture-bound conditions (DSM-IV: Appendix I). Counterpart within the framework of ICD-10 () are the "culture-specific disorders" defined in Annex 2 of the "Diagnostic criteria for research".

More broadly, an epidemic that can be attributed to cultural behavior patterns or suggestion is sometimes referred to as a behavioral epidemic. As in the cases of drug or alcohol abuse or smoking, transmission can be determined by communal reinforcement as well as by person-to-person interactions. On etiological grounds, it can be difficult to distinguish the causal contribution of culture in disease from other environmental factors such as toxicity.

For most balance and gait disorders, some form of displacement exercise is thought helpful (for example walking, jogging, or bicycling but not on a treadmill or stationary bicycle). This has not been well-studied in MdDS. Medications that suppress the nerves and brain circuits involved in balance (for example, the benzodiazepine clonazepam) have been noted to help and can lower symptoms, but it is not a cure. It is not known whether medication that suppress symptoms prolongs symptom duration or not. Vestibular therapy has not proved to be effective in treating MdDS.

Additional research is being undertaken into the neurological nature of this syndrome through imaging studies. The disorder remains incurable and permanent if the symptoms do not remit in a short period of time.

Paris syndrome (, , "Pari shōkōgun") is a transient mental disorder exhibited by some individuals when visiting or going on vacation to Paris, as a result of extreme shock derived from their discovery that Paris is not what they had expected it to be. The syndrome is characterized by a number of psychiatric symptoms such as acute delusional states, hallucinations, feelings of persecution (perceptions of being a victim of prejudice, aggression, or hostility from others), derealization, depersonalization, anxiety, and also psychosomatic manifestations such as dizziness, tachycardia, sweating, and others, such as vomiting. Similar syndromes include Jerusalem syndrome and Stendhal syndrome. The condition is commonly viewed as a severe form of culture shock. It is particularly noted among Japanese travelers.

At least one clinical trial on readaptation of the vestibulo-ocular reflex undertaken by Dr Mingjia Dai from Mount Sinai Hospital in New York City has produced results for a significant percentage of patients who have participated in the program.

Dai has developed an intervention that provided improvement in symptoms for 70% of the patients in the clinical trial phase. The protocol involves a physical manipulation of the patient intended to readapt the vestibulo-ocular reflex. While the program is no longer in the research phase, Dai continues to accept patients. According to Dai, "success" is measured as a 50% reduction of symptoms.

Recent research reveals a very small percentage of MdDS cases may be related to optokinetic nystagmus (OKN).

Professor Hiroaki Ota, a Japanese psychiatrist working in France, is credited as the first person to diagnose the condition in 1986. However, later work by Youcef Mahmoudia, physician with the hospital Hôtel-Dieu de Paris, indicates that Paris syndrome is "a manifestation of psychopathology related to the voyage, rather than a syndrome of the traveller." He theorized that the excitement resulting from visiting Paris causes the heart to accelerate, causing giddiness and shortness of breath, which results in hallucinations in the manner similar to the Stendhal syndrome described by Italian psychiatrist Graziella Magherini in her book "La sindrome di Stendhal".

A culture-specific syndrome is characterized by:

1. categorization as a disease in the culture (i.e., not a voluntary behaviour or false claim);

2. widespread familiarity in the culture;

3. complete lack of familiarity or misunderstanding of the condition to people in other cultures;

4. no objectively demonstrable biochemical or tissue abnormalities (signs);

5. the condition is usually recognized and treated by the folk medicine of the culture.

Some culture-specific syndromes involve somatic symptoms (pain or disturbed function of a body part), while others are purely behavioral. Some culture-bound syndromes appear with similar features in several cultures, but with locally specific traits, such as penis panics.

A culture-specific syndrome is not the same as a geographically localized disease with specific, identifiable, causal tissue abnormalities, such as kuru or sleeping sickness, or genetic conditions limited to certain populations. It is possible that a condition originally assumed to be a culture-bound behavioral syndrome is found to have a biological cause; from a medical perspective it would then be redefined into another nosological category.

Victor Khrisanfovich Kandinsky () (1849, Byankino, Siberia - 1889) was a Russian physician, and was 2nd cousin to famed artist Wassily Kandinsky. He was born in Siberia into a large family of extremely wealthy businessmen.

In 1877 as a military physician in the Balkans during the Russo-Turkish War, he began experiencing mood swings and hallucinations. Kandinsky performed self-diagnosis, and he referred to his mental condition as "Primäre Verrücktheit" (primary paranoid psychosis) which has been anachronistically translated into modern terms as a "schizophrenic-like state". In 1885 Kandinsky published a book written in German on "pseudohallucinations" in which he describes and details hallucinations largely based on his personal experiences. In September 1889, feeling that his psychotic symptoms were returning, he took his own life by taking an overdose of morphine. He died as a patient in the institution he had formerly run as the medical superintendent, the St. Nicholas Asylum in St. Petersburg.

In a monograph published posthumously in 1890, Kandinsky described a condition which involved being alienated from one's personal mental processes, combined with delusions of being physically and mentally influenced by external forces. The syndrome he described is now known as Kandinsky-Clérambault syndrome, named along with French psychiatrist Gaëtan Gatian de Clérambault. The syndrome also known as "syndrome of psychic automatism".

Egomania is also known as an obsessive preoccupation with one's self and applies to someone who follows their own ungoverned impulses and is possessed by delusions of personal greatness and feels a lack of appreciation. Someone suffering from this extreme egocentric focus is an egomaniac. The condition is psychologically abnormal.

The term "egomania" is often used by laypersons in a pejorative fashion to describe an individual who is intolerably self-centred. The clinical condition that most resembles the popular conception of egomania is narcissistic personality disorder.

The cause of Jumping Frenchmen syndrome is unknown. One theory is that it is a genetic condition. Observation of 50 cases found the disorder to be remotely located and concentrated in the northern regions of Maine. Fourteen of these cases were found in four families. Another set of cases were found in a single family where the father, his two sons, and his two grandchildren exhibited "jumping" behavior.

It may also be a culture-bound syndrome or a formed habit. These French "jumpers" lived in a very remote region and most were lumberjacks. This type of small community would allow for a majority to adapt to this sort of reaction. Also, instances of many being shy may imply that the "jumper" was positively reinforced by the sudden attention as the entertainment for a group.

In 1885, Georges Gilles de la Tourette included Jumping Frenchmen syndrome in the typology of "convulsive tic illness"; studies of the condition in the 1980s cast doubt on whether the phenomenon was in fact a physical condition similar to Tourette syndrome. Documentation of direct observation of "Jumping Frenchmen" has been scarce, and while videotape evidence was recorded by several researchers that showed the condition to be real, MH and JM Saint-Hilaire concluded from studying eight affected people that it was brought on by conditions at their lumber camps and was psychological, not neurological.

The Jumping Frenchmen of Maine were a group of 19th-century lumberjacks who exhibited a rare disorder of unknown origin. The syndrome entails an exaggerated startle reflex which may be described as an uncontrollable "jump"; individuals with this condition can exhibit sudden movements in all parts of the body. Jumping Frenchmen syndrome shares some symptoms with other startle disorders.

Individuals with this condition were first found in the Moosehead Lake region of Maine, and were first described by George Miller Beard in 1878.

The Cornelia de Lange Syndrome (CdLS) Foundation is a nonprofit, family support organization based in Avon, Connecticut, that exists to ensure early and accurate diagnosis of CdLS, promote research into the causes and manifestations of the syndrome, and help people with a diagnosis of CdLS, and others with similar characteristics, make informed decisions throughout their lives.

Intermetamorphosis is a delusional misidentification syndrome, related to agnosia. The main symptoms consist of patients believing that they can see others change into someone else in both external appearance and internal personality. The disorder is usually comorbid with neurological disorders or mental disorders.

An example from medical literature is a man who was diagnosed with Alzheimer's disease. After some time he mistook his wife for his deceased mother and later for his sister. As an explanation, he stated that he had never been married or that his wife had left him. Later he mistook his son for his brother and his daughter for another sister. Visual agnosia or prosopagnosia were not diagnosed, as the misidentification also took place during phone calls. On several occasions he mistook the hospital for the church he used to go to.

The disorder was first described in 1932 by P. Courbon and J. Tusques ("Illusions d'intermétamorphose et de la charme"), in the Journal: Annales Medico-Psychologiques issue 14, page 401-406.

Over a century later, the term has re-appeared with a positive gloss to mark the post-modern quest for success and celebrity. 'Self-confidence is the key to all success...Some characterize Trump as an egomaniac...Ross Perot has a similar penchant for egomania'.

By contrast, the reticent are negatively labelled: 'it may well be a form of egomania...if you aren't willing to take a chance'.

“Mongrel complex" ("Complexo de vira-Lata" in Portuguese) is an expression used to refer to a collective inferiority complex felt by some Brazilian people in comparison to Europe or the United States. The reference to a "mongrel" (as opposed to "pure-bred") carries negative connotations attributed to most Brazilians being racially mixed as well as a perception of lacking cultural refinement.

Often, an interdisciplinary approach is recommended to treat the issues associated with CdLS. A team for promoting the child's well-being often includes speech, occupational and physical therapists, teachers, physicians and parents.

Erotomania is a type of delusional disorder where the affected person believes that another person is in love with him or her. This belief is usually applied to someone with higher status or a famous person, but can also be applied to a complete stranger. Erotomanic delusions often occur in patients with schizophrenia and other psychotic disorders, but can also occur during a manic episode in the context of bipolar I disorder. During an erotomanic delusion, the patient believes that a secret admirer is declaring his or her affection for the patient, often by special glances, signals, telepathy, or messages through the media. Usually the patient then returns the perceived affection by means of letters, phone calls, gifts, and visits to the unwitting recipient. Even though these advances are unexpected and often unwanted, any denial of affection by the object of this delusional love is dismissed by the patient as a ploy to conceal the forbidden love from the rest of the world.

Erotomania is also called de Clérambault's syndrome, after French psychiatrist Gaëtan Gatian de Clérambault (1872–1934), who published a comprehensive review paper on the subject ("Les Psychoses Passionnelles") in 1921. Erotomania should not be confused with obsessive love or obsession with unrequited love, neither of which involves delusion.

After the first discovery and description of Marshall–Smith syndrome in 1971, research to this rare syndrome has been carried out.

- Adam, M., Hennekam, R.C.M., Butler, M.G., Raf, M., Keppen, L., Bull, M., Clericuzio, C., Burke, L., Guttacher, A., Ormond, K., & Hoyme, H.E. (2002). Marshall–Smith syndrome: An osteochondrodysplasia with connective tissue abnormalities. 23rd Annual David W. Smith Workshop on Malformations and Morphogenesis, August 7, Clemson, SC.

- Adam MP, Hennekam RC, Keppen LD, Bull MJ, Clericuzio CL, Burke LW, Guttmacher AE, Ormond KE and Hoyme HE: Marshall-Smith Syndrome: Natural history and evidence of an osteochondrodysplasia with connective tissue abnormalities. American Journal of Medical Genetics 137A:117–124, 2005.

- Baldellou Vazquez A, Ruiz-Echarri Zelaya MP, Loris Pablo C, Ferr#{225}ndez Longas A, Tamparillas Salvador M. El sIndrome de Marshall-Smith: a prop#{243}sito de una observad#{243}n personal. An Esp Pediatr 1983; 18:45-50.

- Butler, M.G. (2003). Marshall–Smith syndrome. In: The NORD Guide to Rare Disorders. (pp219–220) Lippincott, Williams & Wilkins, Philadelphia, PA.

- Charon A, Gillerot T, Van Maldergem L, Van Schaftingen MH, de Bont B, Koulischer L. The Marshall–Smith syndrome. Eur J Pediatr 1990; 150: 54-5.

- Dernedde, G., Pendeville, P., Veyckemans, F., Verellen, G. & Gillerot, Y. (1998). Anaesthetic management of a child with Marshall–Smith syndrome. Canadian Journal of Anesthesia. 45 (7): 660. Anaesthetic management of a child with Marshall-Smith syndrome

- Diab, M., Raff, M., Gunther, D.F. (2002). Osseous fragility in Marshall–Smith syndrome. Clinical Report: Osseous fragility in Marshall-Smith syndrome

- Ehresmann, T., Gillessen-Kaesbach G., Koenig R. (2005). Late diagnosis of Marshall Smith Syndrome (MSS). In: Medgen 17.

- Hassan M, Sutton T, Mage K, LimalJM, Rappaport R. The syndrome of accelerated bone maturation in the newborn infant with dysmorphism and congenital malformations: (the so-called Marshall–Smith syndrome). Pediatr Radiol 1976; 5:53-57.

- Hoyme HE and Bull MJ: The Marshall-Smith Syndrome: Natural history beyond infancy. Western Society for Pediatric Research, Carmel, California, February, 1987. Clin Res 35:68A, 1987.

- Hoyme HE and Bull MJ: The Marshall-Smith Syndrome: Natural history beyond infancy. David W. Smith Morphogenesis and Malformations Workshop. Greenville, SC, August, 1987. Proceedings of the Greenwood Genetics Center 7:152, 1988.

- Hoyme HE, Byers PH, Guttmacher AE: Marshall–Smith syndrome: Further evidence of an osteochondrodysplasia in long-term survivors. David W. Smith Morphogenesis and Malformations Workshop, Winston-Salem, NC, August, 1992. Proceedings of the Greenwood Genetic Center 12:70, 1993.

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- Tzu-Jou Wang (2002). Marshall–Smith syndrome in a Taiwanese patient with T-cell immunodeficiency. Am J Med Genet Part A;112 (1):107-108.

Gueules cassées (broken faces) is a French expression for facially disfigured servicemen which originated in World War I. Colonel Yves Picot is said to have coined the term when he was refused passing a checkpoint to a party.

The core symptom of the disorder is that the sufferer holds an unshakable belief that another person is secretly in love with them. In some cases, the sufferer may believe several people at once are "secret admirers". The sufferer may also experience other types of delusions concurrently with erotomania, such as delusions of reference, wherein the perceived admirer secretly communicates his or her love by subtle methods such as body posture, arrangement of household objects, and other seemingly innocuous acts (or, if the person is a public figure, through clues in the media). Erotomanic delusions are typically found as the primary symptom of a delusional disorder or in the context of schizophrenia and may be treated with atypical antipsychotics.

The word neuroleptic originates from the Greek word lepsis ("seizure" or "fit"). Antipsychotics ( neuroleptics or tranquilizers) were investigated by the anesthesiologists De Castro and Mundeleer who coined the term neuroleptanalgesia, an anesthetic process that involves combining a major neuroleptic tranquilizer/antipsychotic with a potent opioid analgesic to produce a detached, pain-free state. This technique was widely used from the 1960s onwards, initially using a combination of phenoperidine and haloperidol, which was subsequently replaced in the early 1980s by a combination of fentanyl and droperidol. Efforts were also made to develop compounds which combined both types of activity in a single molecule. Neuroleptanalgesia results in amnesia among some, but not all, patients. The technique has become less popular with the advent of more modern procedural sedation drug combinations, though it is still rarely used today.

Nicolaides–Baraitser syndrome (NCBRS) is a rare genetic condition caused by de novo missense mutations in the SMARCA2 gene and has only been reported in less than 100 cases worldwide. NCBRS is a distinct condition and well recognizable once the symptoms have been identified.

Kosaki overgrowth syndrome (KOGS) is a rare (27 cases reported by 2017) syndrome caused by mutations in the PDGFRB gene.

Many children affected by alternating hemiplegia also suffer from epilepsy. Seizures may occur during an attack but more often occur between attacks. Anti-epilepsy drugs are given to prevent or lessen the seizures, but the drugs often don’t work and have severe side effects that require the patient to discontinue use. Flunarizine, which blocks calcium channels, is an antiepilepsy drugs used in 50% of patients, and has been shown to shorten the duration of attacks as well as reducing the severity of the attacks. While Flunarizine does not stop the attacks, it is most common drug prescribed to treat those suffering from alternating hemiplegia.