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Depression and major depressive disorder
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Biological basis of depression
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Related terms:
aggression
delusion
depersonalization
emotion
encopresis
enuresis
mental fatigue
malingering
behavioral abnormality
Mental or Behavioral Dysfunction
depression Audio
de·pres·sion [ dih-presh-uhn ]
Subclass of:
Behavioral Symptoms; Emotions
Also called:
Clinical depression; Dysthymic disorder; Major depressive disorder; Unipolar depression
Definitions related to mental depression:
  • (depression) A condition marked by ongoing feelings of sadness, despair, loss of energy, diminished interest/pleasure and difficulty dealing with normal daily life.
    U.S. FDA Glossary
    U.S. Food & Drug Administration, 2021
  • (depression) A melancholy feeling of sadness and despair.
    NCI Thesaurus
    U.S. National Cancer Institute, 2021
  • (depression) A mental condition marked by ongoing feelings of sadness, despair, loss of energy, and difficulty dealing with normal daily life. Other symptoms of depression include feelings of worthlessness and hopelessness, loss of pleasure in activities, changes in eating or sleeping habits, and thoughts of death or suicide. Depression can affect anyone, and can be successfully treated. Depression affects 15-25% of cancer patients.
    NCI Dictionary of Cancer Terms
    U.S. National Cancer Institute, 2021
  • (depression) Depression is a serious medical illness. It's more than just a feeling of being sad or "blue" for a few days. If you are one of the more than 19 million teens and adults in the United States who have depression, the feelings do not go away. They persist and interfere with your everyday life. Symptoms can include Feeling sad or "empty"; Loss of interest in favorite activities; Overeating, or not wanting to eat at all; Not being able to sleep, or sleeping too much; Feeling very tired; Feeling hopeless, irritable, anxious, or guilty; Aches or pains, headaches, cramps, or digestive problems; Thoughts of death or suicide. Depression is a disorder of the brain. There are a variety of causes, including genetic, biological, environmental, and psychological factors. Depression can happen at any age, but it often begins in teens and young adults. It is much more common in women. Women can also get postpartum depression after the birth of a baby. Some people get seasonal affective disorder in the winter. Depression is one part of bipolar disorder. There are effective treatments for depression, including antidepressants, talk therapy, or both. NIH: National Institute of Mental Health
    MedlinePlus
    U.S. National Library of Medicine, 2021
  • (depression) Depressive states usually of moderate intensity in contrast with MAJOR DEPRESSIVE DISORDER present in neurotic and psychotic disorders.
    NLM Medical Subject Headings
    U.S. National Library of Medicine, 2021
  • (depression) Mental state characterized by feelings of sadness, loneliness, despair, low self-esteem and self-reproach; accompanying signs include psychomotor retardation or at times, agitation, withdrawal from interpersonal contact, and vegetative symptoms, such as insomnia and anorexia. The term refers to a mood that is so characterized or a mood disorder.
    Sadock's Comprehensive Glossary of Psychiatry and Psychology
    BJ Sadock Titles Press, 2012
  • (depression) Unpleasant, but not necessarily irrational or pathological, mood state characterized by sadness, despair, or discouragement; "the blues"; may also involve low self-esteem, social withdrawal, and somatic symptoms such as eating and sleep disturbance.
    CRISP Thesaurus
    National Institutes of Health, 2006
  • Depression (also known as major depression or major depressive disorder) is a psychiatric disorder that affects mood, behavior, and overall health. It causes prolonged feelings of sadness, emptiness, or hopelessness, and a loss of interest in activities that were once enjoyed. People with depression may also have changes in appetite (leading to overeating or not eating enough), changes in sleeping patterns (sleeping too much or not being able to sleep), loss of energy, and difficulty concentrating. Although depression is considered primarily a mental health disorder, it can also have physical features including headaches, other unexplained aches and pains, unusually slow or fast movements, and digestive problems. To be diagnosed with depression, an individual must have signs and symptoms nearly every day for at least 2 weeks. However, the features of this condition vary widely. Depression most commonly begins in late adolescence or early adulthood, although it can appear at any age. If untreated, episodes of depression can last for weeks, months, or years, and can go away and come back (recur). Affected individuals may have difficulty functioning in their daily lives, including at school or work. People with depression have a higher risk of substance abuse problems and dying by suicide than the general population. Several health conditions are closely related to depression or have depression as a characteristic feature. These include dysthymia (which has...
    MedlinePlus Genetics
    U.S. National Library of Medicine, 2021
  • (depression) A disorder characterized by melancholic feelings of grief or unhappiness.
    Common Terminology Criteria for Adverse Events
    U.S. National Institutes of Health, 2021
  • Depression is a feeling of sadness and/or a decreased interest or pleasure in activities that becomes a disorder when it is intense enough to interfere with functioning. It may follow a recent loss or other sad event but is out of proportion to that event and lasts beyond an appropriate length of time.
    Merck Manuals
    Merck & Co., Inc., 2020
  • Major depressive disorder has significant potential morbidity and mortality, contributing to suicide (see the image below), incidence and adverse outcomes of medical illness, disruption in interpersonal relationships, substance abuse, and lost work time. With appropriate treatment, 70-80% of individuals with major depressive disorder can...
    Medscape
    WebMD, 2019
  • Depression is a mood disorder that causes a persistent feeling of sadness and loss of interest. Also called major depressive disorder or clinical depression, it affects how you feel, think and behave and can lead to a variety of emotional and physical problems. You may have trouble doing normal day-to-day activities, and sometimes you...
    Mayo Clinic
    Mayo Foundation for Medical Education and Research
  • Depressive disorders are typically characterized by persistent low mood, loss of interest and enjoyment, neurovegetative disturbance, and reduced energy, causing varying levels of social and occupational dysfunction. Depressive symptoms include depressed mood, anhedonia, weight changes, libido changes, sleep disturbance, psychomotor...
    Epocrates
    Athenahealth, Inc., 2019
  • Depression, in psychology, a mood or emotional state that is marked by feelings of low self-worth or guilt and a reduced ability to enjoy life. A person who is depressed usually experiences several of the following symptoms: feelings of sadness, hopelessness, or pessimism; lowered self-esteem and...
    Encyclopedia Britannica
    Encyclopedia Britannica, Inc., 2020
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