Causes of mental disorders

Anxiety

Anxiety disorders are characterised by excessive fear and worry and related behavioural disturbances. Symptoms are severe enough to result in significant distress or significant impairment in functioning.Effective psychological treatment exists, and depending on the age and severity, medication may also be considered.

obsessive compulsive disorder (OCD)
Social Phobias
Generalised anxiety disorder
Panic attacks

Depression

During a depressive episode, the person experiences depressed mood (feeling sad, irritable, empty) or a loss of pleasure or interest in activities, for most of the day, nearly every day, for at least two weeks. People with depression are at an increased risk of suicide. Yet, effective psychological treatment exists, and depending on the age and severity, medication may also be considered.

Lowering of mood
Disassocieted
Reduced energy
Loss of interest and enjoyment

Eating disorder

Eating disorders, such as anorexia nervosa and bulimia nervosa, involve abnormal eating and preoccupation with food as well as prominent body weight and shape concerns. Individuals with bulimia nervosa are at a significantly increased risk for substance use, suicidality, and health complications. Effective treatment options exist, including family-based treatment and cognitive-based therapy. It can affect any age or gender. It can have psychological and physical consequences

Anorexia
Bulimia nervosa
Binge eating Disorder

Schizophrenia

Schizophrenia affects approximately 24 million people or 1 in 300 people worldwide.eople with schizophrenia may experience persistent difficulties with their cognitive functioning. Yet, a range of effective treatment options exist, including medication, psychoeducation, family interventions, and psychosocial rehabilitation.

Psychotic disorder
Disrupts the thinking and emotions
Distorted perception of reality
Hallucinations
Delusions
Thought disorder socail withdraw
Lack of motivation
Impaired thinking and memory

Panic attacks

This ongoing worry and tension may be accompanied by physical symptoms, such as restlessness, feeling on edge or easily fatigued, difficulty concentrating, muscle tension or problems sleeping. The core symptom of panic disorder is recurrent panic attacks, an overwhelming combination of physical and psychological distress. During an attack, several of these symptoms occur in combination.

Sweating
Chest pain
Fear of losing control
Feeling detached
Trembling or shaking
Lightheaded or faint
Rapid heart beat
Chills or hot flashes
Feeling shortness of breath

A mental disorder is an impairment of the mind disrupting normal thinking, feeling, mood, behavior, or social interactions, and accompanied by significant distress or dysfunction.^[1]^[2]^[3]^[4] The causes of mental disorders are very complex and vary depending on the particular disorder and the individual. Although the causes of most mental disorders are not fully understood, researchers have identified a variety of biological, psychological, and environmental factors that can contribute to the development or progression of mental disorders.^[5] Most mental disorders result in a combination of several different factors rather than just a single factor.^[6]

^ "Mental, behavioural or neurodevelopmental disorders". International Classification of Diseases for Mortality and Morbidity Statistics, 11th rev. (ICD-11 MMS). World Health Organization. April 2019. Retrieved 2019-10-30. Mental, behavioural and neurodevelopmental disorders are syndromes characterized by clinically significant disturbance in an individual's cognition, emotional regulation, or behaviour that reflects a dysfunction in the psychological, biological, or developmental processes that underlie mental and behavioural functioning. These disturbances are usually associated with distress or impairment in personal, family, social, educational, occupational, or other important areas of functioning.
^ Webster's Third New International Dictionary, (Springfield, MA: Merriam-Webster, 1961, rev. 2016), ("mental illness noun, variants: or mental disorder or less commonly mental disease, Definition of mental illness: any of a broad range of medical conditions (such as major depression, schizophrenia, obsessive compulsive disorder, or panic disorder) that are marked primarily by sufficient disorganization of personality, mind, or emotions to impair normal psychological functioning and cause marked distress or disability and that are typically associated with a disruption in typical thinking, feeling, mood, behavior, interpersonal interactions, or daily functioning").
^ American Heritage Dictionary of the English Language, 5th ed. (Boston: Houghton Mifflin Harcourt, 2011, rev. 2018), ("mental disorder, n. - Any of various disorders, such as schizophrenia, bipolar disorder, or autism spectrum disorder, characterized by a distressing or disabling impairment of an individual's cognitive, emotional, or social functioning.")
^ Oxford English Dictionary, 3rd ed. (Oxford, UK: Oxford University Press, September 2001), ("II. Senses relating to the mind in an unhealthy or abnormal state. 5. a. Designating a temporary or permanent impairment of the mind due to inherited defect, injury, illness, or environment, usually needing special care or rehabilitation. Esp. in mental breakdown, mental deficiency, mental disease, mental disorder, mental incapacity, mental retardation, etc.; see also mental illness n. at Compounds. ... mental illness n. a condition which causes serious abnormality in a person's thinking or behaviour, esp. one requiring special care or treatment; a psychiatric illness. Now somewhat dated, and sometimes avoided as being potentially offensive.").
^ Arango C, Díaz-Caneja CM, McGorry PD, Rapoport J, Sommer IE, Vorstman JA, et al. (July 2018). "Preventive strategies for mental health". The Lancet. Psychiatry. 5 (7): 591–604. doi:10.1016/S2215-0366(18)30057-9. hdl:11370/92f1a79c-f53d-47ae-be92-7a4c8d4b4e25. PMID 29773478. S2CID 21703364.
^ Clark LA, Cuthbert B, Lewis-Fernández R, Narrow WE, Reed GM (September 2017). "Three Approaches to Understanding and Classifying Mental Disorder: ICD-11, DSM-5, and the National Institute of Mental Health's Research Domain Criteria (RDoC)". Psychological Science in the Public Interest. 18 (2): 72–145. doi:10.1177/1529100617727266. PMID 29211974. S2CID 206743519. ... research has shown that psychopathology generally arises from multiple biological, behavioral, psychosocial, and cultural factors, all interacting in complex ways and filtered through an individual's lifetime of experience. Research also has shown that the outcomes of these factors and their interactions are not clearly definable, distinct diseases, but are instead complex and variable combinations of psychological problems.

[1] "Mental, behavioural or neurodevelopmental disorders". International Classification of Diseases for Mortality and Morbidity Statistics, 11th rev. (ICD-11 MMS). World Health Organization. April 2019. Retrieved 2019-10-30. Mental, behavioural and neurodevelopmental disorders are syndromes characterized by clinically significant disturbance in an individual's cognition, emotional regulation, or behaviour that reflects a dysfunction in the psychological, biological, or developmental processes that underlie mental and behavioural functioning. These disturbances are usually associated with distress or impairment in personal, family, social, educational, occupational, or other important areas of functioning.

[2] Webster's Third New International Dictionary, (Springfield, MA: Merriam-Webster, 1961, rev. 2016), ("mental illness noun, variants: or mental disorder or less commonly mental disease, Definition of mental illness: any of a broad range of medical conditions (such as major depression, schizophrenia, obsessive compulsive disorder, or panic disorder) that are marked primarily by sufficient disorganization of personality, mind, or emotions to impair normal psychological functioning and cause marked distress or disability and that are typically associated with a disruption in typical thinking, feeling, mood, behavior, interpersonal interactions, or daily functioning").

[3] American Heritage Dictionary of the English Language, 5th ed. (Boston: Houghton Mifflin Harcourt, 2011, rev. 2018), ("mental disorder, n. - Any of various disorders, such as schizophrenia, bipolar disorder, or autism spectrum disorder, characterized by a distressing or disabling impairment of an individual's cognitive, emotional, or social functioning.")

[4] Oxford English Dictionary, 3rd ed. (Oxford, UK: Oxford University Press, September 2001), ("II. Senses relating to the mind in an unhealthy or abnormal state. 5. a. Designating a temporary or permanent impairment of the mind due to inherited defect, injury, illness, or environment, usually needing special care or rehabilitation. Esp. in mental breakdown, mental deficiency, mental disease, mental disorder, mental incapacity, mental retardation, etc.; see also mental illness n. at Compounds. ... mental illness n. a condition which causes serious abnormality in a person's thinking or behaviour, esp. one requiring special care or treatment; a psychiatric illness. Now somewhat dated, and sometimes avoided as being potentially offensive.").

[5] Arango C, Díaz-Caneja CM, McGorry PD, Rapoport J, Sommer IE, Vorstman JA, et al. (July 2018). "Preventive strategies for mental health". The Lancet. Psychiatry. 5 (7): 591–604. doi:10.1016/S2215-0366(18)30057-9. hdl:11370/92f1a79c-f53d-47ae-be92-7a4c8d4b4e25. PMID 29773478. S2CID 21703364.

[pmid29211974-6] Clark LA, Cuthbert B, Lewis-Fernández R, Narrow WE, Reed GM (September 2017). "Three Approaches to Understanding and Classifying Mental Disorder: ICD-11, DSM-5, and the National Institute of Mental Health's Research Domain Criteria (RDoC)". Psychological Science in the Public Interest. 18 (2): 72–145. doi:10.1177/1529100617727266. PMID 29211974. S2CID 206743519. ... research has shown that psychopathology generally arises from multiple biological, behavioral, psychosocial, and cultural factors, all interacting in complex ways and filtered through an individual's lifetime of experience. Research also has shown that the outcomes of these factors and their interactions are not clearly definable, distinct diseases, but are instead complex and variable combinations of psychological problems.

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