A mental health disorder characterized by persistently depressed mood or loss of interest in activities, causing significant impairment in daily life.

Possible causes include a combination of biological, psychological, and social sources of distress. Increasingly, research suggests these factors may cause changes in brain function, including altered activity of certain neural circuits in the brain.

The persistent feeling of sadness or loss of interest that characterizes major depression can lead to a range of behavioral and physical symptoms. These may include changes in sleep, appetite, energy level, concentration, daily behavior, or self-esteem. Depression can also be associated with thoughts of suicide.

The mainstay of treatment is usually medication, talk therapy, or a combination of the two. Increasingly, research suggests these treatments may normalize brain changes associated with depression.


Cluster Number:
Wiki Number: W058
Diagnoses: Depression
US Patients:
World Patients: 300Mil; 4.4%
Sex Ratio: M;W+
Age Onset:
Brain Area:
Symptoms: low mood and aversion to activity; loss of pleasure;
Effects: the leading cause of disability world-wide;
Causes: childhood adversity ,unequal treatment of siblings, abuse; adult work-or-family stress, medical diagnosis, unemployment
Medications: antidepressants should not be used with initial encounters; long-term depression can benefit from medical help
Therapies: exercise, fond memories; self-help books;


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