Any illness with a psychological origin, manifested either in symptoms of emotional distress or in abnormal behaviour. Most mental disorders can be broadly classified as either psychoses or neuroses (see neurosis; psychosis). Psychoses (e.g., schizophrenia and bipolar disorder) are major mental illnesses characterized by severe symptoms such as delusions, hallucinations, and an inability to evaluate reality in an objective manner. Neuroses are less severe and more treatable illnesses, including depression, anxiety, and paranoia as well as obsessive-compulsive disorders and post-traumatic stress disorders. Some mental disorders, such as Alzheimer disease, are clearly caused by organic disease of the brain, but the causes of most others are either unknown or not yet verified. Schizophrenia appears to be partly caused by inherited genetic factors. Some mood disorders, such as mania and depression, may be caused by imbalances of certain neurotransmitters in the brain; they are treatable by drugs that act to correct these imbalances (see psychopharmacology). Neuroses often appear to be caused by psychological factors such as emotional deprivation, frustration, or abuse during childhood, and they may be treated through psychotherapy. Certain neuroses, particularly the anxiety disorders known as phobias, may represent maladaptive responses built up into the human equivalent of conditioned reflexes.
Learn more about mental disorder with a free trial on Britannica.com.
Mental illness characterized by the alternation of manic and depressive states. Depression is the more common symptom, and many patients experience only a brief period of overoptimism and mild euphoria during the manic phase. The condition, which seems to be inheritable, probably arises from malregulation of the amines norepinephrine, dopamine, and 5-hydroxytryptamine. It is most commonly treated with lithium carbonate.
Learn more about bipolar disorder with a free trial on Britannica.com.
It is sometimes considered a synonym for disease. Others maintain that fine distinctions exist. Some have described illness as the subjective perception by a patient of an objectively defined disease.
The mode of being healthy includes, as defined by the World Health Organization, " [...] a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity". When these conditions are not fulfilled, then one can be considered to have an illness or be ill. Medication and the science of pharmacology is used to cure or reduce symptoms of an illness or medical conditions. Developmental disability is a term used to describe severe, life-long disabilities attributable to mental and/or physical impairments.
Social determinants of health are the social conditions in which people live which determine their health. Illnesses are generally related to social, economic, political, and environmental circumstances. Social determinants of health have been recognized by several health organizations such as the Public Health Agency of Canada and the World Health Organization to greatly influence collective and personal well-being.
Medical emergencies are injuries or illnesses that pose an immediate threat to a person's health or life which require help from a doctor or hospital. The doctor's specialization of emergency medicine includes techniques for effective handling of medical emergencies and resuscitation of patients. Emergency departments provides initial treatment to patients with a broad spectrum of illnesses and injuries, some of which may be life-threatening and requiring immediate attention.
A drug is any chemical substance other than a food or device that affects the function of living things. Drugs can be used to treat illness, or they can be used recreationally to alter behavior and perception. Medications are typically produced by pharmaceutical companies and are often patented. Those that are not patented are called generic drugs. Some drugs, if misused, can overwhelm the homeostasis of a living organism, causing severe illness or death. Essentially it is a type of poisoning. In the context of biology, poisons are substances that can cause illness.
Bedrest as a medical treatment refers to staying in bed day and night, as in a treatment for a hangover. Even though most patients in hospitals spend most of their time in the hospital beds, bedrest more often refers to an extended period of recumbence at home.
Human enhancement technologies (HET) are technologies that can be used not simply for treating illness and disability, but also for enhancing human capacities and characteristics. Medication is a licenced drug taken to cure or reduce symptoms of an illness or medical condition. A wheelchair is mobility device that takes the form of a chair on wheels, used by people for whom walking is difficult or impossible due to illness or disability.
Shock therapy is the deliberate and controlled induction of some form of physiological state of shock in an individual for the purpose of psychiatric treatment. Electrotherapy is the use of electrical energy in the treatment of impairments of health and a conditions of abnormal functioning.
Behavioral medicine is an interdisciplinary field of medicine concerned with the development and integration of psychosocial, behavioral and biomedical knowledge relevant to health and illness. Clinical Global Impression scale to assess treatment response in patients with mental disorders. It's " Improvement scale" requires the clinician to rate how much the patient's illness has improved or worsened relative to a baseline state. Mental confusion and decreased alertness may indicate that a chronic illness has gotten worse.
Korean Shamanism involves notions of "spirit sickness".
Folk medicine is collectively procedures traditionally used for treatment of illness and injury, aid to childbirth, and maintenance of wellness. It is a body of knowledge distinct from "scientific medicine" and may coexist in the same culture.