Finding a therapist

This page is reference information compiled from the cited sources. It is not medical advice. For any decision about health, diagnosis or care, consult a qualified professional.

What it is

A mental disorder is a behavioral or mental pattern that causes significant distress or impairment of personal functioning. It is characterized by a clinically significant disturbance in an individual's cognition, emotional regulation, or behavior. Such disturbances may occur as single episodes, may be persistent, or may be relapsing–remitting. There are many different types of mental disorders, with signs and symptoms that vary widely between specific disorders. A mental disorder is one aspect of mental health. According to the DSM-5, it is a syndrome characterized by clinically significant disturbance in an individual's cognition, emotion regulation, or behavior that reflects a dysfunction in the psychological, biological, or developmental processes underlying mental functioning.

Key facts

Disorders are usually diagnosed or assessed by a mental health professional, such as a clinical psychologist, psychiatrist, psychiatric nurse, or clinical social worker. Common treatment options are psychotherapy or psychiatric medication, while lifestyle changes, social interventions, peer support, and self-help are also options. Services for mental disorders are usually based in psychiatric hospitals, outpatient clinics, or in the community. The causes of mental disorders are often unclear, and theories incorporate findings from a range of fields. Cultural and religious beliefs, as well as social norms, should be taken into account when making a diagnosis. The two widely established classification systems are the International Classification of Diseases (ICD) and the Diagnostic and Statistical Manual of Mental Disorders (DSM). Stigma and discrimination can add to the suffering and disability associated with mental disorders.

When to seek professional help

The source associates professional care with situations where there is a behavioral or mental pattern that causes significant distress or impairment of personal functioning. Professional assessment is indicated for a clinically significant disturbance in an individual's cognition, emotional regulation, or behavior. This includes disturbances associated with distress, disability, increased risk of death, or a significant loss of autonomy. The source notes that a mental health crisis, such as a nervous breakdown, manifests as severe, stress-induced depression, anxiety, paranoia, or dissociation to the extent that a previously functional individual is no longer able to function on a day-to-day basis. Professional diagnosis is relevant for specific conditions like major depression, dementia, bipolar disorder, schizophrenia, and neurodevelopmental disorders such as ADHD and autism.

Source: Mental disorder (CC BY-SA 4.0 (Wikipedia)), retrieved 2026-10-05.