MSbP is rare. A recent systematic study in Italy found that in a series of over 700 patients admitted to a pediatric ward, 4 cases met the diagnostic criteria for MSbP (0.53%). In this study, stringent diagnostic criteria were used, which required at least one test outcome or event that could not possibly have occurred without deliberate intervention by the MSbP person.

One study showed that in 93 percent of MSbP cases, the abuser is the mother or another female guardian or caregiver. This may be attributed to the prevalent socialization pattern that places females in the primary care-taking role. Of course, it could also be a gender trait rooted in genetics, as it is easy to see how females who seek attention as victims could gain an evolutionary advantage, while men seeking the same would be unfavoured for physical protection and mating. A psychodynamic model of this kind of maternal abuse exists.

MSbP may be more prevalent in the parents of those with a learning difficulty or mental incapacity, and as such the apparent patient could, in fact, be an adult.

Fathers and other male caregivers have been the perpetrators in only 7% of the cases studied. When they are not actively involved in the abuse, the fathers or male guardians of MSbP victims are often described as being distant, emotionally disengaged, and powerless. These men play a passive role in MSbP by being frequently absent from the home and rarely visiting the hospitalized child. Usually, they vehemently deny the possibility of abuse, even in the face of overwhelming evidence or their child's pleas for help.

Overall, male and female children are equally likely to be the victim of MSbP. In the few cases where the father is the perpetrator, however, the victim is three times more likely to be male.

People who demonstrate factitious disorders often claim to have physical ailments or be recovering from the consequences of stalking, victimization, harassment, and sexual abuse. Several behaviors present themselves to suggest factors beyond genuine problems. After studying 21 cases of deception, Feldman listed the following common behavior patterns in people who exhibited Munchausen by Internet:

- Medical literature from websites or textbooks is often duplicated or discussed in great detail.

- The length and severity of purported physical ailments conflicts with user behavior. Feldman uses the example of someone posting in considerable detail about being in septic shock, when such a possibility is extremely unlikely.

- Symptoms of ailments may be exaggerated as they correspond to a user's misunderstanding of the nature of an illness.

- Grave situations and increasingly critical prognoses are interspersed with "miraculous" recoveries.

- A user's posts eventually reveal contradictory information or claims that are implausible: for example, other users of a forum may find that a user has been divulging contradictory information about occurrence or length of hospital visits.

- When attention and sympathy decreases to focus on other members of the group, a user may announce that other dire events have transpired, including the illness or death of a close family member.

- When faced with insufficient expressions of attention or sympathy, a forum member claims this as a cause that symptoms worsen or do not improve.

- A user resists contact beyond the Internet, such as by telephone or personal visit, often claiming bizarre reasons for not being able to accept such contact.

- Further emergencies are described with inappropriate happiness, designed to garner immediate reactions.

- The posts of other forum members exhibit identical writing styles, spelling errors, and language idiosyncrasies, suggesting that the user has created fictitious identities to move the conversation in their direction.

The term "Munchausen by Internet" was first used in an article published in the "Southern Medical Journal" written by Marc Feldman in 2000. Feldman, a clinical professor of psychiatry at the University of Alabama at Birmingham, gave a name to the phenomenon in 2000, but he co-authored an article on the topic two years earlier in the "Western Journal of Medicine", using the description "virtual factitious disorder". Factitious disorders are described in the "Diagnostic and Statistical Manual of Mental Disorders: DSM-IV-TR" (DSM) as psychological disorders involving the production of non-existent physical or psychological ailments to earn sympathy. These illnesses are feigned not for monetary gain or to avoid inconvenient situations, but to attract compassion or to control others. Chronic manifestation of factitious disorder is often called Munchausen syndrome, after a book about the exaggerated accounts of the adventures of Baron Munchausen, a German cavalry officer in the Russian Army, that was written by Rudolf Erich Raspe. When the symptoms of another person, such as a child or an elderly parent, are purposely induced by the caregiver, it is called factitious disorder imposed on another, or Munchausen syndrome by proxy.

Feldman noted that the advent of online support groups, combined with access to vast stores of medical information, enabled individuals seeking to gain sympathy by relating a series of harrowing medical or psychological problems that defy comprehension to misuse the groups. Communication forums specializing in medical or psychological recovery were established to give lay users support in navigating often confusing and frustrating medical processes and bureaucracy. Communities often formed on those forums, with the goal of sharing information to help other members. Medical websites also became common, giving lay users access to literature in a way that was accessible to those without specific medical training. As Internet communication grew in popularity, users began to forgo the doctors and hospitals often consulted for medical advice. Frequenting virtual communities that have experience with a medical problem, Feldman notes, is easier than going through the physical pain or illness that would be necessary before visiting a doctor to get the attention sought. By pretending to be gravely ill, Internet users can gain sympathy from a group whose sole reason for existence is support. Health care professionals, with their limited time, greater medical knowledge, and tendency to be more skeptical in their diagnoses, may be less likely to provide that support.

Factitious disorder imposed on another, also known as Munchausen syndrome by proxy (MSbP), is a condition where a caregiver or spouse fabricates, exaggerates, or induces mental or physical health problems in those who are in their care, with the primary motive of gaining attention or sympathy from others. The name is derived from the term Munchausen syndrome, a psychiatric factitious disorder wherein those affected feign disease, illness, or psychological trauma to draw attention, sympathy, or reassurance to themselves. However, unlike Munchausen syndrome, in MSbP, the deception involves not themselves, but rather someone under the person's care. MSbP is primarily distinguished from other forms of abuse or neglect by the motives of the perpetrator. Some experts consider it to be an elusive, potentially lethal, and frequently misunderstood form of child abuse or medical neglect. However, others consider the concept to be problematic, since it is based largely on supposition regarding a person's motives, which can be open to radically different interpretations.

Factitious disorder imposed on another has also spawned much heated controversy within the legal and social services communities. In a handful of high-profile cases, mothers who have had several children die from sudden infant death syndrome have been declared to have MSbP. Based on MSbP testimony of an expert witness, they were tried for murder, convicted, and imprisoned for several years. In some cases, that testimony was later impeached, resulting in exoneration of those defendants.

Otherkin largely identify as mythical creatures, with others identifying as creatures from fantasy or popular culture. Examples include: angels, demons, dragons, goats, elves, fairies, sprites, aliens, and cartoon characters. Many otherkin believe in the existence of a multitude of parallel universes, and their belief in the existence of supernatural or sapient non-human beings is grounded in that idea.

With regards to their online communities, otherkin largely function without formal authority structures, and mostly focus on support and information gathering, often dividing into more specific groups based on kintype. There are occasional offline gatherings, but the otherkin network is mostly an online phenomenon.

Some otherkin (such as elvenkin) state they are allergic to iron (and products of modern technology), while others (such as dragonkin) state that having no allergies is a sign of otherkin condition. Some otherkin also claim to be especially empathic and attuned to nature. Some state to be able to shapeshift mentally or astrally, meaning that they experience the sense of being in their particular form while not actually changing physically.

The therian and vampire subcultures are related to the otherkin community, and are considered part of it by most otherkin, but are culturally and historically distinct movements of their own, despite some overlap in membership.

Video game addiction (VGA) is a hypothetical behavioral addiction characterized by excessive or compulsive use of computer games or video games, which interferes with a person's everyday life. Video game addiction may present itself as compulsive gaming, social isolation, mood swings, diminished imagination, and hyper-focus on in-game achievements, to the exclusion of other events in life.

In May 2013, the American Psychiatric Association (APA) proposed criteria for video game addiction in the 5th edition of the "Diagnostic and Statistical Manual of Mental Disorders", concluding that there was insufficient evidence to include it as an official mental disorder. However, proposed criteria for "Internet Gaming Disorder" were included in a section called "Conditions for Further Study".

While Internet gaming disorder is proposed as a disorder, it is still discussed how much this disorder is caused by the gaming activity itself, or whether it is to some extent an effect of other disorders. Contradictions in research examining video game addictiveness may reflect more general inconsistencies in video game research. For example, while some research has linked violent video games with increased aggressive behavior other research has failed to find evidence for such links.

Otherkin are a subculture who socially and spiritually identify as partially or entirely non-human. Some of them surmise that they are, either spiritually or genetically, not human; however, this claim is unsubstantiated. This is explained by some members of the otherkin community as possible through reincarnation, having a non-human soul, ancestry, or symbolic metaphor. Some scholars categorize this identity claim as "religious", because it is largely based on supernatural beliefs. Adherents more typically deny the religiosity of otherkinism, referring to it instead as simply a congenital condition, or a metaphysical state of being.

A disability pretender is subculture term meaning a person who behaves as if he or she were disabled. It may be classified as a type of factitious disorder or as a medical fetishism.

One theory is that pretenders may be the "missing link" between devotees and wannabes, demonstrating an assumed continuum between those merely attracted to people with disabilities and those who actively wish to become disabled. Many wannabes use pretending as a way to appease the intense emotional pain related to having body integrity identity disorder.

Pretending takes a variety of forms. Some chatroom users on internet sites catering to devotees have complained that chat counterparts they assumed were female were revealed as male devotees. This form of pretending (where a devotee derives pleasure by pretending to be a disabled woman) may indicate a very broad predisposition to pretending among devotees.

Pretending includes dressing and acting in ways typical of disabled people, including making use of aids (Walking sticks, crutches, wheelchairs, mobility scooters, white canes, etc. Pretending may also take the form of a devotee persuading his or her sexual partner to play the role of a disabled person. Pretending may be practiced in private, in intimacy, or in public, and may occupy surprisingly long periods. In the latter case, some pretenders hope that the disability may become permanent, such as through tissue necrosis caused by constricted blood supply.

Cyberchondria, otherwise known as 'compucondria', is the unfounded escalation of concerns about common symptomology based on review of search results and literature online. Articles in popular media position cyberchondria anywhere from temporary neurotic excess to adjunct hypochondria. Cyberchondria is a growing concern among many healthcare practitioners as patients can now research any and all symptoms of a rare disease, illness or condition, and manifest a state of medical anxiety.

Attraction to disability or devotism is a sexualised interest in the appearance, sensation and experience of disability. It may extend from normal human sexuality into a type of sexual fetishism. Sexologically, the pathological end of the attraction tends to be classified as a paraphilia. (Note, however, that the very concept "paraphilia" continues to elude satisfactory definition and remains a subject of ongoing debate in both professional and lay communities) Other researchers have approached it as a form of identity disorder. The most common interests are towards amputations, prosthesis, and crutches.

Some theorists focus on presumed built-in reward systems of the games to explain their potentially addictive nature. Many video games, particularly massively multiplayer online role-playing games and social network and mobile games, rely on a "compulsion loop" or "core loop", a cycle of activities that involve rewarding the player and driving them to continue through another cycle, retaining them in the game. The anticipation of such rewards can create a neurological reaction that releases dopamine into the body, so that once the reward is obtained, the person will remember it as a pleasurable feeling. This has been found similar to the same neurological reaction believed to be associated with gambling addiction. In reference to gamers such as one suicide in China, the head of one software association was quoted, "In the hypothetical world created by such games, they become confident and gain satisfaction, which they cannot get in the real world."

Griffiths has also proposed that another reason why online video games are potentially addictive is because they "can be played all day every day". The fact that there is no end to the game can feel rewarding for some, and hence players are further engaged in the game.

A high prenatal testosterone load may be a risk factor for the development of video game addiction in adulthood.

Ferguson, Coulson and Barnett in a meta-analytic review of the research, concluded that the evidence suggests that video game addiction arises out of other mental health problems, rather than causing them. Thus it is unclear whether video game addiction should be considered a unique diagnosis.

Researchers at the University of Rochester and Immersyve, Inc. (a Celebration, Florida, computer gaming think-tank) investigated what motivates gamers to continue playing video games.

According to lead investigator Richard Ryan, they believe that players play for more reasons than fun alone.

Ryan, a motivational psychologist at Rochester, says that many video games satisfy basic psychological needs, and players often continue to play because of rewards, freedom, and a connection to other players.

Michael Brody, M.D., head of the TV and Media Committee of the American Academy of Child and Adolescent Psychiatry, stated in a 2007 press release that "... there is not enough research on whether or not video games are addictive". However, Brody also cautioned that for some children and adolescents, "... it displaces physical activity and time spent on studies, with friends, and even with family".

Karen Pierce, a psychiatrist at Chicago's Children's Memorial Hospital, sees no need for a specific gaming addiction diagnosis. Two or more children see her each week because of excessive computer and video game play, and she treats their problems as she would any addiction. She said one of her excessive-gaming patients "...hasn't been to bed, hasn't showered...He is really a mess".

In factitious disorder imposed on self, the affected person exaggerates or creates symptoms of illnesses in themselves to gain examination, treatment, attention, sympathy, and/or comfort from medical personnel. In some extreme cases, people suffering from Munchausen syndrome are highly knowledgeable about the practice of medicine and are able to produce symptoms that result in lengthy and costly medical analysis, prolonged hospital stays, and unnecessary operations. The role of "patient" is a familiar and comforting one, and it fills a psychological need in people with this syndrome. This disorder is distinct from hypochondriasis and other somatoform disorders in that those with the latter do not intentionally produce their somatic symptoms. Munchausen syndrome is distinct from other psychiatric disorders such as malingering in that Munchausen does not fabricate symptoms for material gain such as financial compensation, absence from work, or access to drugs.

Risk factors for developing factitious disorder include childhood traumas, growing up with parents/caretakers who were emotionally unavailable due to illness or emotional problems, a serious illness as a child, failed aspirations to work in the medical field, personality disorders, and low self-esteem. Factitious disorder is more common in men and is seen in young or middle-aged adults. Those with a history of working in healthcare are also at greater risk of developing it.

Arrhythmogenic Munchausen syndrome describes individuals who simulate or stimulate cardiac arrhythmias to gain medical attention.

A similar behavior called factitious disorder imposed on another has been documented in the parent or guardian of a child. The adult ensures that his or her child will experience some medical affliction, therefore compelling the child to suffer through treatments and spend a significant portion of their youth in hospitals. Furthermore, a disease may actually be initiated in the child by the parent or guardian. This condition is considered distinct from Munchausen syndrome. There is growing consensus in the pediatric community that this disorder should be renamed "medical abuse" to highlight the harm caused by the deception and to make it less likely that a perpetrator can use a psychiatric defense when harm is done.

Until the 1990s, it tended to be described mostly as acrotomophilia, at the expense of other disabilities, or of the wish by some to pretend or acquire disability. Bruno (1997) systematised the attraction as factitious disability disorder. A decade on, others argue that erotic target location error is at play, classifying the attraction as an identity disorder. In the standard psychiatric reference "Diagnostic and Statistical Manual of Mental Disorders", text revision (DSM-IV-tr), the fetish falls under the general category of "Sexual and Gender Identity Disorders" and the more specific category of paraphilia, or sexual fetishes; this classification is preserved in DSM-5.

Apotemnophilia has been studied for a number of years to determine whether this disorder is actually neurological or psychological. However, in-depth research related to apotemnophilia and its correlation to the mind and body are still not clear. Recent research has shown small breakthroughs such that apotemnophiles are three times more likely to want removal of a left limb than right, in accordance with damage to the right parietal lobe, and also in concordance with sufferers of somatoparaphrenia; in addition, skin conductance response is significantly different above and below the line of desired amputation, and the line of desired amputation remains stable over time, with the desire often beginning in early childhood. Among a convenience sample of 52 apotemnophiles recruited from internet groups, the great majority wanted a single leg removed, cut above the knee. There are parallels between apotemnophilia as a motivation for body integrity identity disorder and autogynephilia as a motivation for some cases of male-to-female gender dysphoria.

A 2014 review concluded that

Exhibitionism is the act of exposing in a public or semi-public context those parts of one's body that are not normally exposed – for example, the breasts, genitals or buttocks. The practice may arise from a desire or compulsion to expose themselves in such a manner to groups of friends or acquaintances, or to strangers for their amusement or sexual satisfaction or to shock the bystander. Exposing oneself only to an intimate partner is normally not regarded as exhibitionism. In law, the act of exhibitionism may be called indecent exposure, "exposing one's person", or other expressions.

Kimberly Young indicates that previous research links internet/computer addiction with existing mental health issues, most notably depression. She states that computer addiction has significant effects socially such as low self-esteem, psychologically and occupationally which led many subjects to academic failure.

According to a Korean study on internet/computer addiction, pathological use of the internet results in negative life impacts such as job loss, marriage breakdown, financial debt, and academic failure. 70% of internet users in Korea are reported to play online games, 18% of which are diagnosed as game addicts which relates to internet/computer addiction. The authors of the article conducted a study using Kimberly Young's questionnaire. The study showed that the majority of those who met the requirements of internet/computer addiction suffered from interpersonal difficulties and stress and that those addicted to online games specifically responded that they hoped to avoid reality.

Because there is uncertainty in treating suspected factitious disorder imposed on self, some advocate that health care providers first explicitly rule out the possibility that the person has another early-stage disease. Then they may take a careful history and seek medical records to look for early deprivation, childhood abuse, or mental illness. If a person is at risk to themself, psychiatric hospitalization may be initiated.

Healthcare providers may consider working with mental health specialists to help treat the underlying mood or disorder as well as to avoid countertransference. Therapeutic and medical treatment may center on the underlying psychiatric disorder: a mood disorder, an anxiety disorder, or borderline personality disorder. The patient's prognosis depends upon the category under which the underlying disorder falls; depression and anxiety, for example, generally respond well to medication and/or cognitive behavioral therapy, whereas borderline personality disorder, like all personality disorders, is presumed to be pervasive and more stable over time, and thus offers a worse prognosis.

People affected may have multiple scars on their abdomen due to repeated "emergency" operations.

Candaulism is a sexual practice or fantasy in which a man exposes his female partner, or images of her, to other people for their voyeuristic pleasure.

The term may also be applied to the practice of undressing or otherwise exposing a female partner to others, or urging or forcing her to engage in sexual relations with a third person, such as during a swinging activity. Similarly, the term may also be applied to the posting of personal images of a female partner on the internet or urging or forcing her to wear clothing which reveals her physical attractiveness to others, such as by wearing very brief clothing, such as a microskirt, tight-fitting or see-through clothing or a low-cut top.

There are many possible causes for this disorder. One such possibility is an underlying personality disorder. Individuals with FD may be trying to repeat a satisfying childhood relationship with a doctor. Perhaps also an individual has a desire to deceive or test authority figures. The underlying desire to resume the role of a patient and be cared for can also be considered an underlying personality disorder. Abuse, neglect, or abandonment during childhood are also probable causes.

These individuals may be trying to reenact unresolved issues with their parents. A history of frequent illnesses may also contribute to the development of this disorder. In some cases, individuals afflicted with FD are accustomed to actually being sick, and thus return to their previous state to recapture what they once considered the 'norm.' Another cause is a history of close contact with someone (a friend or family member) who had a severe or chronic condition. The patients found themselves subconsciously envious of the attention said relation received, and felt that they themselves faded into the background. Thus medical attention makes them feel glamorous and special.

Apotemnophia / Body Integrity Disorder (BIID) is a is a rare, infrequently studied and highly secretive condition in which there is a mismatch between the mental body image and the physical body. Apotemnomphilia is characterized by an intense desire for amputation of a limb. Currently BIID is not included in the International Statistical Classification of Diseases 11 or the Diagnostic and Statistical Manual of Mental Disorders IV. It is often not known to surgeons, neurologists and psychiatrists. BIID individuals typically avoid healthcare and often act out their desires by pretending they are disabled or perform actual self-amputation.

A 2012 study concluded, based on interviews with 54 individuals, that the main rationale for their desire for body modification (amputation) was to feel complete or to feel satisfied inside. Based on the results of the survey, researchers concluded that psychotherapy was often supportive, but did not help diminishing BIID symptoms. Individuals reported that antidepressants were helpful in reducing depressive symptoms related to BIID, but that antipsychotics were not. Actual amputation of the limb was effective in all 7 cases who had surgical treatment.

The term "klismaphilia" was coined in 1973 by Dr. Joanne Denko, an early investigator in this field, to describe the activities of some of her patients. A person with klismaphilia is a "klismaphile" or "klismaphiliac".

Computer addiction can be described as the excessive or compulsive use of the computer which persists despite serious negative consequences for personal, social, or occupational function. Another clear conceptualization is made by Block, who stated that "Conceptually, the diagnosis is a compulsive-impulsive spectrum disorder that involves online and/or offline computer usage and consists of at least three subtypes: excessive gaming, sexual preoccupations, and e-mail/text messaging". While it was expected that this new type of addiction would find a place under the compulsive disorders in the DSM-5, the current edition of the "Diagnostic and Statistical Manual of Mental Disorders", it is still counted as an unofficial disorder. The concept of computer addiction is broadly divided into two types, namely offline computer addiction and online computer addiction. The term offline computer addiction is normally used when speaking about excessive gaming behavior, which can be practiced both offline and online. Online computer addiction, also known as Internet addiction, gets more attention in general from scientific research than offline computer addiction, mainly because most cases of computer addiction are related to the excessive use of the Internet.

Although addiction is usually used to describe dependence on substances, addiction can also be used to describe pathological Internet use. Experts on Internet addiction have described this syndrome as an individual being intensely working on the Internet, prolonged use of the Internet, uncontrollable use of the Internet, unable to use the Internet with efficient time, not being interested in the outside world, not spending time with people from the outside world, and an increase in their loneliness and dejection. However, simply working long hours on the computer does not necessarily mean someone is addicted.

Bondage pornography is the depiction of sexual bondage or other BDSM activities using photographs, stories, movies or drawings. Though often described as pornography, the genre involves the presentation of bondage fetishism or BDSM scenarios and does not necessarily involve the commonly understood pornographic styles. In fact, the genre is primarily interested with the presentation of a bondage scene and less with depictions of sexuality, such as nudity or sex scenes, which may be viewed as a distraction from the aesthetics and eroticism of the bondage scenario itself.

Historically, most subjects of bondage imagery have been women, and the genre has been criticized for promoting misogynistic attitudes and violence against women.

Klismaphiles can gain satisfaction of enemas through fantasies, by actually receiving or giving one, or through the process of eliminating steps to being administered one (e.g., under the pretense of being constipated). Klismaphilia is practiced by men and women, although men are more likely to be klismaphiles, as with most paraphilias. Klismaphiles might gain pleasure from a large, water distended belly or the feeling of internal pressure. Often, klismaphiles report discovering these desires after a chance administration of an enema sometime in their childhood, but some do report discovering these feelings later on. Klismaphilia is practiced both heterosexually and homosexually. The paraphilia may be used as a substitute or as an auxiliary by its practitioners for genital sexual activity. Usually, klismaphiles carry out normal lives and successfully engage in this behavior secretly. If this is the case they will probably try to conceal the pleasure they receive from these administrations.

For administering enemas not intended for medical purposes there are specialty items, such as the aluminium nozzle shown to the right, that are commonly used in activities involving klismaphilia. Such items are available on the Internet and in sex shops in a great variety of sizes, styles, and materials.

Vorarephilia (often shortened to vore) is a paraphilia characterized by the erotic desire to be consumed by, or sometimes to personally consume, another person or creature, or an erotic attraction to the process of eating in general. Since vorarephilic fantasies cannot usually be acted out in reality, they are often expressed in stories or drawings shared on the Internet. The word "vorarephilia" is derived from the Latin "vorare" (to "swallow" or "devour"), and Ancient Greek φιλία ("philía", "love").

The fantasy usually involves the victim being swallowed whole, though occasionally the victims are chewed up, and digestion may or may not be included. Vore fantasies are separated from sexual cannibalism because the living victim is normally swallowed whole. Sometimes the consumers are human, but anthropormorphized animals, dragons, and enormous snakes also appear frequently in these fantasies. After consumption, the enlarged belly of the consumer is often described with great care. Vorarephiles sometimes prefer to differentiate between "soft vore" and "hard vore"; soft vore means the victim is swallowed whole and alive, and may possibly come back out in the case of a "non-fatal" scenario, while in hard vore the victim goes through a more gruesome, realistic digestion process, often getting chewed up beforehand.

Vore is most often enjoyed through pictures, stories, videos, and video games, and it can appear in mainstream media. In some cases, vorarephilia may be described as a variation of macrophilia and may combine with other paraphilias. Apart from macrophilia, vore fantasies often have themes of BDSM, microphilia, pregnancy fetishism, furry fetishism, "unbirthing" (a desire to be swallowed whole into the vagina and returned to the uterus), and sexual cannibalism.

One case study analysis connected the fantasy with sexual masochism, and suggested that it could be motivated by a desire to merge with a powerful other or permanently escape loneliness. With "no known treatment" for vorarephiles who feel ill at ease with their sexuality, psychologists at Toronto's Centre for Addiction and Mental Health have recommended trying to "adjust to, rather than change or suppress" the sexual interest. Medication for sex drive reduction could be used if deemed necessary.