Psychopathology in non-human primates has been studied since the mid 20th century. Over 20 behavioral patterns in captive chimpanzees have been documented as (statistically) abnormal for their frequency, severity or oddness - some of which have also been observed in the wild. Captive great apes show gross behavioral abnormalities such as stereotypy of movements, self-mutilation, disturbed emotional reactions (mainly fear or aggression) towards companions, lack of species-typical communications, and generalized learned helplessness. In some cases such behaviors are hypothesized to be equivalent to symptoms associated with psychiatric disorders in humans such as depression, anxiety disorders, eating disorders and post-traumatic stress disorder. Concepts of antisocial, borderline and schizoid personality disorders have also been applied to non-human great apes.

The risk of anthropomorphism is often raised with regard to such comparisons, and assessment of non-human animals cannot incorporate evidence from linguistic communication. However, available evidence may range from nonverbal behaviors - including physiological responses and homologous facial displays and acoustic utterances - to neurochemical studies. It is pointed out that human psychiatric classification is often based on statistical description and judgement of behaviors (especially when speech or language is impaired) and that the use of verbal self-report is itself problematic and unreliable.

Psychopathology has generally been traced, at least in captivity, to adverse rearing conditions such as early separation of infants from mothers; early sensory deprivation; and extended periods of social isolation. Studies have also indicated individual variation in temperament, such as sociability or impulsiveness. Particular causes of problems in captivity have included integration of strangers in to existing groups and a lack of individual space, in which context some pathological behaviors have also been seen as coping mechanisms. Remedial interventions have included careful individually-tailored re-socialization programs, behavior therapy, environment enrichment, and on rare occasions psychiatric drugs. Socialization has been found to work 90% of the time in disturbed chimpanzees, although restoration of functional sexuality and care-giving is often not achieved
Laboratory researchers sometimes try to induce symptoms in animals through genetic, neurological or behavioral manipulation, although this has been criticized on empirical grounds and opposed on animal rights grounds. The modern city, in connection with the psychological disorders of its residents, has been described as a human zoo.

Employment discrimination is reported to play a significant part in the high rate of unemployment among those with a diagnosis of mental illness. Schemes to combat stigma have been prioritized by global and national psychiatric organizations, but their methods and outcomes have been criticized as counterproductive

People with mental disorders are often afraid of violence against them. Over a quarter of individuals accessing community mental health services in a US inner-city area are victims of at least one violent crime in a given year, a proportion eleven times higher than the inner-city average. The proportion is many times greater in every category of crime, including rape/sexual assault, other violent assaults, and personal and property theft. Findings consistently indicate that it is many times more likely that people diagnosed with a serious mental illness living in the community will be the victims rather than the perpetrators of violence.

However, fear of unpredictable violent acts by people with mental illness is also common. One US national survey indicated that a far higher percentage of Americans rated individuals described as displaying the characteristics of a mental disorder (for example Schizophrenia or Substance Use Disorder) as “likely to do something violent to others” compared to those described as being ‘troubled’. Research indicates, on balance, a higher than average number of violent acts by some individuals with certain diagnoses, notably antisocial or psychopathic personality disorders, but conflicting findings about specific symptoms (for example links between psychosis and violence in community settings) - but the mediating factors of such acts are most consistently found to be mainly socio-demographic and socio-economic factors such as being young, male, of lower socio-economic status and, in particular, substance abuse (including alcohol). For the most serious crimes, such as homicide, some diagnoses are over-represented in arrests/convictions; however, although high-profile cases have lead to fears that this has increased due to deinstitutionalization, this does not reflect the evidence.

Violence related to mental disorder typically occurs in the context of complex social interactions, often in a family setting rather than between straingers. It is also an issue in healthcare settings[78] and the wider community

The general public have been found to hold a strong stereotype of dangerousness and desire for social distance from individuals described as mentally ill

Media coverage of mental illness comprises predominantly negative depictions, for example, of incompetence, violence or criminality, with far less coverage of positive issues such as accomplishments or human rights issues.[ Such negative depictions, including in children’s cartoons, are thought to contribute to stigma and negative attitudes in the public and in those with mental health problems themselves, although more sensitive or serious cinematic portrayals have increased in prevalence. In the United States, The Carter Center has created fellowships for journalists in South Africa, the U.S., and Romania, to enable reporters to research and write stories on mental health topics. Former U.S. First Lady Rosalynn Carter began the fellowships not only to train reporters in how to sensitively and accurately discuss mental health and mental illness, but also to increase the number of stories on these topics in the news media

Three quarters of countries around the world have mental health legislation. Compulsory admission to mental health facilities (also known as Involuntary commitment or sectioning), is a controversial topic. From some points of view it can impinge on personal liberty and the right to choose, and carry the risk of abuse for political, social and other reasons; from other points of view, it can potentially prevent harm to self and others, and assist some people in attaining their right to healthcare when unable to decide in their own interests.

All human-rights oriented mental health laws require proof of the presence of a mental disorder as defined by internationally accepted standards, but the type and severity of disorder that counts can vary in different jurisdictions. The two most often utilized grounds for involuntary admission are said to be serious likelihood of immediate or imminent danger to self or others, and the need for treatment. Applications for someone to be involuntarily admitted may usually come from a mental health practitioner, a family member, a close relative, or a guardian. Human-rights-oriented laws usually stipulate that independent medical practitioners or other accredited mental health practitioners must examine the patient separately and that there should be regular, time-bound review by an independent review body. An individual must be shown to lack the capacity to give or withhold informed consent (i.e. to understand treatment information and its implications). Proxy consent (also known as substituted decision-making) may be given to a personal representative, a family member or a legally appointed guardian, or patients may have been able to enact an advance directive as to how they wish to be treated. The right to supported decision-making may also be included in legislation. Involuntary treatment laws are increasingly extended to those living in the community, for example outpatient commitment laws (known by different names) are used in New Zealand, Australia, United Kingdom and most of the United States.

The World Health Organization reports that in many instances national mental health legislation takes away the rights of persons with mental disorders rather than protecting rights, and is often outdated. In 1991, the United Nations adopted the Principles for the Protection of Persons with Mental Illness and the Improvement of Mental Health Care, which established minimum human rights standards of practice in the mental health field. In 2006 the UN formally agreed the Convention on the Rights of Persons with Disabilities to protect and enhance the rights and opportunities of disabled people, including those with psychosocial disabilities

The term insanity, sometimes used colloquially as a synonym for mental illness, is often used technically as a legal term.

The Consumer/Survivor Movement (also known as user/survivor movement) is made up of individuals (and organizations representing them) who are clients of mental health services or who consider themselves “survivors” of mental health services. The movement campaigns for improved mental health services and for more involvement and empowerment within mental health services, policies and wider society. Patient advocacy organizations have expanded with increasing deinstitutionalization in developed countries, working to challenge the stereotypes, stigma and exclusion associated with psychiatric conditions. An antipsychiatry movement fundamentally challenges mainstream psychiatric theory and practice, including the reality or utility of psychiatric diagnoses of mental illnesses

A large proportion of individuals who suffer from the symptoms of a mental illness will avoid seeking treatment for their symptoms because of the social stigmaassociated with having a mental illness. The US Surgeon General acknowledged this in 1999:

Powerful and pervasive, stigma prevents people from acknowledging their own mental health problems, much less disclosing them to others.

As a result many people feel the need to keep their mental illness a secret, and will deny the symptoms that they are experiencing. Two thirds of the people who would benefit from treatment for a mental illness do not receive treatment. As with many physical illnesses, the prognoses of a mental illness can worsen the longer that a mental illness remains untreated. The added anxiety of fearing a mental illness diagnoses can also be detrimental to an individual’s mental health, this effect can greatly exacerbate an anxiety disorder or mood disorder. Efforts are being undertaken worldwide to eliminate the stigma of mental illness

A number of professions have developed that specialise in the treatment of mental disorders, including the medical speciality of psychiatry (including psychiatric nursing), the division of psychology known as clinical psychology,[Social Work, as well as Mental Health Counselors, Marriage and Family Therapists, Psychotherapists, Counselors and Public Health professionals. Those with personal experience of using mental health services are also increasingly involved in researching and delivering mental health services and working as mental health professionals. The different clinical and scientific perspectives draw on diverse fields of research and theory, and different disciplines may favor differing models, explanations and goals

Mental disorders have been found to be relatively common, with more than one in three people in most countries reporting sufficient criteria for at least one diagnosis at some point in their life up to the time they were assessed A new WHO global survey currently underway indicates that anxiety disorders are the most common in all but 1 country, followed by mood disorders in all but 2 countries, while substance disorders and impulse-control disorders were consistently less prevalent. Rates varied by region. Such statistics are widely believed to be underestimates, due to poor diagnosis (especially in countries without affordable access to mental health services) and low reporting rates, in part because of the predominant use of self-report data rather than semi-structured instruments.[citation needed] Actual lifetime prevalence rates for mental disorders are estimated to be between 65% and 85%.[citation needed]

A review of anxiety disorder surveys in different countries found average lifetime prevalence estimates of 16.6%, with women having higher rates on average.[ A review of mood disorder surveys in different countries found lifetime rates of 6.7% for major depressive disorder (higher in some studies, and in women) and 0.8% for bipolar 1 disorder.

The updated US National Comorbidity Survey (NCS) reported that nearly half of Americans (46.4%) meet criteria at some point in their life for either an anxiety disorder (28.8%), mood disorder (20.8%), im

A 2004 cross-Europe study found that approximately one in four people reported meeting criteria at some point in their life for at least one of the DSM-IV disorders assessed, which included mood disorders (13.9%), anxiety disorders (13.6%) or alcohol disorder (5.2%). Approximately one in ten met criteria within a 12-month period. Women and younger people of either gender showed more cases of disorder. A 2005 review of surveys in 16 European countries found that 27% of adult Europeans are affected by at least one mental disorder in a 12 month period

An international review of studies on the prevalence of schizophrenia found an average (median) figure of 0.4% for lifetime prevalence; it was consistently lower in poorer countries.

Studies of the prevalence of personality disorders (PDs) have been fewer and smaller-scale, but one broad Norwegian survey found a five-year prevalence of almost 1 in 7 (13.4%). Rates for specific disorders ranged from 0.8% to 2.8%, differing across countries, and by gender, educational level and other factors. A US survey that incidentally screened for personality disorder found a rate of 14.79%.
Approximately 7% of a preschool pediatric sample were given a psychiatric diagnosis in one clinical study, and approximately 10% of 1- and 2-year-olds receiving developmental screening have been assessed as having significant emotional/behavioral problems based on parent and pediatrician reports.

There is substantial variation over time between disorders, and between individuals. Functional ability may also vary across different domains. There may be remission of symptoms, but also relapse. Rates of recovery vary. A number of individual and social factors have been linked to prognosis.

Despite often being characterized in purely negative terms, mental disorders can involve above-average creativity, non-conformity, goal-striving, meticulousness, or empathy. The public perception of the level of disability associated with mental disorders can change

Electroconvulsive therapy (ECT) is sometimes used in severe cases when other interventions for severe intractable depression have failed. Psychosurgery is considered experimental but is used by certain neurologists in certain rare cases.[22][23]

Psychoeducation may be used to provide people with the information to understand and manage their problems. Creative therapies are sometimes used, including music therapy, art therapy or drama therapy. Lifestyle adjustments and supportive measures are often used, including peer support, self-help groups for mental health and supported housing or supported employment (including social firms). Some advocate dietary supplements. Many things have been found to help at least some people. A placebo effect may play a role in any intervention.

A major option for many mental disorders is psychiatric medication. There are several main groups. Antidepressants are used for the treatment of clinical depression as well as often for anxiety and other disorders. There are a number of antidepressants beginning with the tricylics, moving through a wide variety of drugs that modify various facets of the brain chemistry dealing with intercellular communication. Beta-blockers, developed as a heart medication, is also used as an antidepressant. Anxiolytics are used for anxiety disorders and related problems such as insomnia. Mood stabilizers are used primarily in bipolar disorder. Lithium A (a metal) and Lamictal (an epileptic drug) are notable for treating both mania and depression. The others, mainly targeting mania rather than depression, are a wide variety of epilepsy medications and antipsychotics. Antipsychotics are used for psychotic disorders, notably for positive symptoms in schizophrenia. Stimulants are commonly used, notably for ADHD. Despite the different conventional names of the drug groups, there can be considerable overlap in the kinds of disorders for which they are actually indicated. There may also be off-label use. There can be problems with adverse effects and adherence.

A major option for many mental disorders is psychotherapy. There are several main types. Cognitive behavioral therapy (CBT) is widely used and is based on modifying the patterns of thought and behavior associated with a particular disorder. Psychoanalysis, addressing underlying psychic conflicts and defenses, has been a dominant school of psychotherapy and is still in use. Systemic therapy or family therapy is sometimes used, addressing a network of significant others as well as an individual. Some psychotherapies are based on a humanistic approach. There are a number of specific therapies used for particular disorders, which may be offshoots or hybrids of the above types. Mental health professionals often employ an eclectic or integrative approach. Much may depend on the therapeutic relationship, and there may be problems with trust, confidentiality and engagement.

Treatment and support may be provided in psychiatric hospitals, clinics or any of a diverse range of community mental health services. Often an individual may engage in different treatment modalities. Individuals may be treated against their will in some cases. Services in some countries are increasingly based on a Recovery model that supports an individual’s personal journey to regain a meaningful life