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.

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.

The Dorian Gray syndrome arises from the concurring and overlapping clinical concepts of the narcissistic personality, dysmorphophobia, and paraphilia. Psychodynamically, the man afflicted with DGS presents an interplay among his narcissistic tendencies ("timeless beauty"), his arrested development (inability to psychologically mature), and his use of "medical lifestyle" products and services — hair restoration, drugs (for impotence, weight-loss, and mood modification), laser dermatology, and plastic surgery — in order to remain young.

Although the DGS patient displays diagnostic features of said mental disorders, the syndrome describes a common, underlying psychodynamics of mental illness, which is characterized by narcissistic defences against time-dependent maturation, expressed by actively seeking the timeless beauty of youth. The article "Das Dorian Gray syndrom" (2005) reported that approximately 3.0 per cent of the population of Germany present features of the Dorian Gray syndrome.

Clinical vampirism, more commonly called Renfield's syndrome or Renfield syndrome, is an obsession with drinking blood. The earliest formal presentation of clinical vampirism to appear in the psychiatric literature, with the psychoanalytic interpretation of two cases, was contributed by Richard L. Vanden Bergh and John F. Kelley in 1964. As the authors point out, brief and sporadic reports of blood-drinking behaviors associated with sexual pleasure have appeared in the psychiatric literature at least since 1892 with the work of Austrian forensic psychiatrist Richard von Krafft-Ebing. Many medical publications concerning clinical vampirism can be found in the literature of forensic psychiatry, with the unusual behavior reported as one of many aspects of extraordinary violent crimes. The behavior has never gained official recognition by the psychiatric profession and is not found in any edition of the "International Classification of Diseases" or the "Diagnostic and Statistical Manual of Mental Disorders".

The diagnostic criteria for Dorian Gray syndrome are:

- Signs of dysmorphophobia

- Arrested development (inability to mature)

- Using at least two different medical-lifestyle products and services:

- Hair-growth restoration (e.g. finasteride)

- Antiadiposita to lose weight (e.g. orlistat)

- Anti-impotence drugs (e.g. sildenafil)

- Anti-depressant drugs (e.g. fluoxetine)

- Cosmetic dermatology (e.g. laser resurfacing)

- Cosmetic surgery (e.g. a face-lift, liposuction)

Amafufunyana is an unspecified "culture-bound" syndrome named by the traditional healers of the Xhosa people that relates to claims of demonic possession due to members of the Xhosa people exhibiting aberrant behavior and psychological concerns. After study, it was discovered that this term is directed toward people suffering from varying types of schizophrenia. A similar term, ukuthwasa, is used to refer to positive types of claimed possession, though this event also involves those suffering from schizophrenia. It has also found cultural usage among some groups of Zulu peoples.

The direct translation of the term "amafufunyana" is nerves and is a part of a much more complex cultural ideology connecting varying types of psychosis with religious, social, and recently psychiatric beliefs and activities. In a 1998 interview with Xhosa people suffering from schizophrenia by Lund et al., it was determined that through interaction with scientists and psychological services, the preferred treatment for the cultural condition had shifted from relation to traditional healers to active psychiatric assessment.

The symptoms of the syndrome of subjective doubles are not clearly defined in medical literature, however, there are some defining features of the delusion:

- The existence of the delusion, by definition, is not a widely accepted cultural belief.

- The patient insists that the double he/she sees is real even when presented with contradictory evidence.

- Paranoia and/or spatial visualization ability impairments are present.

Similarities to other disorders are often noted in literature. Prosopagnosia, or the inability to recognize faces, may be related to this disorder due to the similarity of symptoms. Subjective doubles syndrome is also similar to delusional autoscopy, also known as an out-of-body experience, and therefore is occasionally referred to as an "autoscopic type" delusion. However, subjective doubles delusion differs from an autoscopic delusion: autoscopy often occurs during times of extreme stress, and can usually be treated by relieving the said stressor.

The syndrome of subjective doubles is usually accompanied by another mental disorder or organic brain syndrome, and may appear during or after the onset of the other disorder. Often, co-occurrence of subjective doubles with other types of delusional misidentification syndromes, especially Capgras syndrome, also occurs.

Several variations of the syndrome have been reported in literature:

- The doubles may appear at different ages of oneself.

- Some patients describe their double as both a physically and psychologically identical copy, rather than a purely physical copy. This is also known as clonal pluralization of the self, another type of delusional misidentification syndrome that may or may not be the same type of disorder (see #Controversy, below). In this case, depersonalization may be a symptom.

- Reverse subjective doubles occurs when the patient believes his/her own self (either physical or mental) is being transformed into another person. (see the case of Mr. A in #Presentation)

Piblokto is an abrupt dissociative episode with four phases: social withdrawal, excitement, convulsions and stupor, and recovery.

Symptoms are often identified as being in one of three categories:

1. panic, discomfort, and uncontrolled spontaneous movement;

2. sensory problems, such as visual or auditory hallucination; and

3. irrational beliefs.

Somatic symptoms can include sensations and pain in head, chest and back, abdomen, limbs, or whole body; whereas, mental and emotional symptoms can include neurasthenia, affective disorder, self-consciousness, hallucination, and paranoia.

"The following case describes a patient who was diagnosed with psychotic depression, bipolar disorder, and the syndrome of subjective doubles:"

Taken from Kamanitz et al., 1989:

"The following case describes a patient who has been diagnosed with schizoaffective disorder along with multiple delusional misidentification syndromes (subjective doubles, Capgras delusion, intermetamorphosis)":

Taken from Silva et al., 1994:

"The following case describes a patient who has been diagnosed with chronic paranoid schizophrenia and reverse subjective doubles:"

Taken from Vasavada and Masand, 1992:

In the DSM-5 the disorder has been renamed somatic symptom disorder (SSD), and includes SSD with predominantly somatic complaints (previously referred to as somatization disorder), and SSD with pain features (previously known as pain disorder).

The likely course and outcome of mental disorders varies and is dependent on numerous factors related to the disorder itself, the individual as a whole, and the social environment. Some disorders are transient, while others may be more chronic in nature.

Even those disorders often considered the most serious and intractable have varied courses i.e. schizophrenia, psychotic disorders, and personality disorders. Long-term international studies of schizophrenia have found that over a half of individuals recover in terms of symptoms, and around a fifth to a third in terms of symptoms and functioning, with some requiring no medication. At the same time, many have serious difficulties and support needs for many years, although "late" recovery is still possible. The World Health Organization concluded that the long-term studies' findings converged with others in "relieving patients, carers and clinicians of the chronicity paradigm which dominated thinking throughout much of the 20th century."

Around half of people initially diagnosed with bipolar disorder achieve syndromal recovery (no longer meeting criteria for the diagnosis) within six weeks, and nearly all achieve it within two years, with nearly half regaining their prior occupational and residential status in that period. However, nearly half go on to experience a new episode of mania or major depression within the next two years. Functioning has been found to vary, being poor during periods of major depression or mania but otherwise fair to good, and possibly superior during periods of hypomania in Bipolar II.

While the Chinese Society of Psychiatry prefers the term "qigong deviation", the American Psychiatric Association uses psychosis terminology. Some physicians believe that this disease can be categorized as a culture-bound syndrome, but this point is debated.

Affected individuals believe that they are in the process of transforming into an animal or have already transformed into an animal. It has been associated with the altered states of mind that accompany psychosis (the that typically involves delusions and hallucinations) with the transformation only seeming to happen in the mind and behavior of the affected person.

A study on lycanthropy from the McLean Hospital reported on a series of cases and proposed some diagnostic criteria by which lycanthropy could be recognised:

- A patient reports in a moment of lucidity or reminiscence that they sometimes feel as an animal or have felt like one.

- A patient behaves in a manner that resembles animal behavior, for example howling, growling, or crawling.

According to this criteria, either a delusional belief in current or past transformation or behavior that suggests a person thinks of themselves as transformed is considered evidence of clinical lycanthropy. The authors note that, although the condition seems to be an expression of psychosis, there is no specific diagnosis of mental or neurological illness associated with its behavioral consequences.

DSM-IV Criteria

Clinical Lycanthropy is thought to be a cultural manifestation of schizophrenia due to the first 4 symptomatic criteria. The first criteria are delusions, and this fits clinical lycanthropy because a person believing that he or she turns into an animal is a delusion. The second symptom is hallucination, and people with clinical lycanthropy have vivid hallucinations of being an animal, and having traits that animal has, whether it be claws, fur, fangs, or whatever that particular animal has. The next symptom is disorganized speech, from a certain human, cultural perspective. The people who have the diagnosis of clinical lycanthropy often emit the sounds of the animal which they believe they become. So, if a person believes that he or she is a werewolf, they may begin to howl under the moon or sometimes even in the daylight. The last symptom that matches schizophrenia is grossly disorganized behavior. This is appropriate because individuals with clinical lycanthropy often act like the animal they believe they have become, including living outside and changing their diet.

It also seems that lycanthropy is not specific to an experience of human-to-wolf transformation; a wide variety of creatures have been reported as part of the shape-shifting experience. A review of the medical literature from early 2004 lists over thirty published cases of lycanthropy, only the minority of which have wolf or dog themes. Canines are certainly not uncommon, although the experience of being transformed into a hyena, cat, horse, bird or tiger has been reported on more than one occasion. Transformation into frogs, and even bees, has been reported in some instances. In Japan, transformation into foxes and dogs was usual (, ). A 1989 case study described how one individual reported a serial transformation, experiencing a change from human to dog, to horse, and then finally cat, before returning to the reality of human existence after treatment. There are also reports of people who experienced transformation into an animal only listed as "unspecified".

There is a case study of a psychiatric patient who had both clinical lycanthropy and Cotard delusion. The term "ophidianthropy" refers to the delusion that one has been transformed into a snake. Two case studies have been reported.

Queen bee syndrome was first defined by G.L. Staines, T.E. Jayaratne, and C. Tavris in 1973. It describes a woman in a position of authority who views or treats subordinates more critically if they are female. This phenomenon has been documented by several studies. In another study, scientists from the University of Toronto speculated that the queen bee syndrome may be the reason that women find it more stressful to work for women managers; no difference was found in stress levels for male workers. An alternate, though closely related, definition describes a queen bee as one who has succeeded in her career, but refuses to help other women do the same.

In ICD-10, the latest version of the International Statistical Classification of Diseases and Related Health Problems, somatization syndrome is described as:

ICD-10 also includes the following subgroups of somatization syndrome:

- Undifferentiated somatoform disorder

- Hypochondriasis

- Somatoform autonomic dysfunction

- Persistent somatoform pain disorder

- Other somatoform disorders, such ones predominated by dysmenorrhoea, dysphagia, pruritus and torticollis

- Somatoform disorder, unspecified

According to Shear et al. (2011):

- The person has been bereaved (i.e. experienced the death of a loved one) for at least six months

- At least one of the following symptoms of persistent, intense, acute grief has been present for a period longer than is expected by others in the person’s social (or cultural) environment:

- Persistent intense yearning or longing for the person who died

- Frequent intense feelings of loneliness, or that life is empty or meaningless without the person who died

- Recurrent thoughts that it is unfair, meaningless or unbearable to live when a loved one has died, or a recurrent urge to die in order to find (or join) the deceased

- Frequent preoccupying thoughts about the person who died; e.g. thoughts or images of the person intrude on activities or interfere with functioning

- At least two of the following symptoms are present for at least one month:

- Frequent, troubling rumination about the circumstances (or consequences) of the death (concerns about how or why the person died, about not being able to manage without their loved one, thoughts of having let the deceased person down, etc.)

- Recurrent feeling of disbelief or inability to accept the death

- Persistent feeling of shock; feeling stunned, dazed or emotionally numb since the death

- Recurrent feelings of anger or bitterness related to the death

- Persistent difficulty trusting or caring about other people, or envy of others who have not experienced a similar loss

- Frequently experiencing pain (or other symptoms) that the deceased person had, hearing the voice of (or seeing) the deceased person

- Experiencing intense emotional or physiological reactivity to memories of the person who died or to reminders of the loss

- Changes in behavior due to avoidance (or its opposite, excessive proximity-seeking—refraining from going places, doing things, or having contact with things that are reminders of the loss; feeling drawn to reminders of the person—wanting to see, touch, hear or smell things to feel close to the person who died). Both symptoms may coexist in the same individual.

- Duration of symptoms and impairment of at least one month

- Symptoms cause clinically significant distress or impairment in social, occupational or other major areas of functioning, where impairment is not explicable as a culturally appropriate response

A mental disorder, also called a mental illness or psychiatric disorder, is a behavioral or mental pattern that causes significant distress or impairment of personal functioning. Such features may be persistent, relapsing and remitting, or occur as a single episode. Many disorders have been described, with signs and symptoms that vary widely between specific disorders. Such disorders may be diagnosed by a mental health professional.

The causes of mental disorders are often unclear. Theories may incorporate findings from a range of fields. Mental disorders are usually defined by a combination of how a person behaves, feels, perceives, or thinks. This may be associated with particular regions or functions of the brain, often in a social context. A mental disorder is one aspect of mental health. Cultural and religious beliefs, as well as social norms, should be taken into account when making a diagnosis.

Services are based in psychiatric hospitals or in the community, and assessments are carried out by psychiatrists, psychologists, and clinical social workers, using various methods but often relying on observation and questioning. Treatments are provided by various mental health professionals. Psychotherapy and psychiatric medication are two major treatment options. Other treatments include social interventions, peer support, and self-help. In a minority of cases there might be involuntary detention or treatment. Prevention programs have been shown to reduce depression.

Common mental disorders include depression, which affects about 400 million, dementia which affects about 35 million, and schizophrenia, which affects about 21 million people globally. Stigma and discrimination can add to the suffering and disability associated with mental disorders, leading to various social movements attempting to increase understanding and challenge social exclusion.

One important factor may be differences or changes in parts of the brain known to be involved in representing body shape (e.g., see proprioception and body image). A neuroimaging study of two people diagnosed with clinical lycanthropy showed that these areas display unusual activation, suggesting that when people report their bodies are changing shape, they may be genuinely perceiving those feelings.

Complicated grief is considered when an individual’s ability to resume normal activities and responsibilities is continually disrupted beyond six months of bereavement. Six months is considered to be the appropriate point of CGD consideration, since studies show that most people are able to integrate bereavement into their lives by this time.

Susto may be a culturally dependent variation of the symptoms of panic attack, distinct from anxiety and depressive disorders.

The condition was explained as being a result of exhaustion of the central nervous system's energy reserves, which Beard attributed to modern civilization. Physicians in the Beard school of thought associated neurasthenia with the stresses of urbanization and with stress suffered as a result of the increasingly competitive business environment. Typically, it was associated with upper class people and with professionals working in sedentary occupations, but really can apply to anyone who lives within the monetary system.

Freud included a variety of physical symptoms in this category, including fatigue, dyspepsia with flatulence, and indications of intra-cranial pressure and spinal irritation. In common with some other people of the time, he believed this condition to be due to "non-completed coitus" or the non-completion of the higher cultural correlate thereof, or to "infrequency of emissions" or the infrequent practice of the higher cultural correlate thereof. Later, Freud formulated that in cases of coitus interruptus as well as in cases of masturbation, there was "an insufficient libidinal discharge" that had a poisoning effect on the organism, in other words, neurasthenia was the result of (auto-)intoxication. Eventually he separated it from anxiety neurosis, though he believed that a combination of the two conditions existed in many cases.

Piblokto, also known as pibloktoq and Arctic hysteria, is a condition most commonly appearing in Inughuit (Greenlandic Inuit) societies living within the Arctic Circle. Piblokto is a culture-specific hysterical reaction in Inuit, especially women, who may perform irrational or dangerous acts, followed by amnesia for the event. Piblokto may be linked to repression of the personality of Inuit women. The condition appears most commonly in winter. It is considered to be a form of a culture-bound syndrome, although more recent studies (see "Skepticism" section) question whether it exists at all. Piblokto is also part of the glossary of cultural bound syndromes found in the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV).

Courtship disorder is a theoretical construct in sexology in which a certain set of paraphilias are seen as specific instances of anomalous courtship instincts in men. The specific paraphilias are biastophilia (paraphilic rape), exhibitionism, frotteurism, telephone scatologia, and voyeurism. According to the "courtship disorder hypothesis", there is a species-typical courtship process in human males consisting of four phases, and anomalies in different phases result in one of these paraphilic sexual interests. That is, instead of being independent paraphilias, this theory sees these sexual interests as individual symptoms of a single underlying disorder.

Neurasthenia is a term that was first used at least as early as 1829 to label a mechanical weakness of the "nerves" and would become a major diagnosis in North America during the late nineteenth and early twentieth centuries after neurologist George Miller Beard reintroduced the concept in 1869.

As a psychopathological term, the first to publish on neurasthenia was Michigan alienist E. H. Van Deusen of the Kalamazoo asylum in 1869, followed a few months later by New York neurologist George Beard, also in 1869 to denote a condition with symptoms of fatigue, anxiety, headache, heart palpitations, high blood pressure, neuralgia, and depressed mood. Van Deusen associated the condition with farm wives made sick by isolation and a lack of engaging activity, while Beard connected the condition to busy society women and overworked businessmen.

Neurasthenia is currently a diagnosis in the World Health Organization's International Classification of Diseases (and the Chinese Society of Psychiatry's Chinese Classification of Mental Disorders). However, it is no longer included as a diagnosis in the American Psychiatric Association's "Diagnostic and Statistical Manual of Mental Disorders".

Americans were said to be particularly prone to neurasthenia, which resulted in the nickname "Americanitis" (popularized by William James). Another, rarely used, term for neurasthenia is nervosism.