What Is Depression? - Symptoms, Treatment & Causes

Instructor: Ron Fritz
In this lesson you will learn the difference between the feeling of depression and Major Depressive Disorder, or Major Depression. You will also learn about the causes behind Major Depression and what the current treatments are for people suffering from the disorder.

Picture yourself sitting on a beach. As you look out over the ocean, you see a storm approaching. As it moves closer, the sky darkens, and everyone on the beach moves away, leaving you all alone. You begin to feel a chill, but you are unable to get out of the way of the oncoming storm. Finally, the rain comes and you are enveloped in a tempest gale with flashing lightening and roaring thunder. Now imagine it is all in your mind, and you will have an inkling of what someone with Major Depression feels when they go into a depressive episode.

Depression Comparisons

Major Depressive Disorder, commonly referred to as MDD or Major Depression, is different from the situational depression you feel from the loss of a loved one or being fired from your job. Although the feeling of depression that stems from those situations is very real, it is as similar to Major Depression as a headache is to a migraine. Unlike situational depression, Major Depression can cause an individual to feel depressed without any identifiable reason.

Major Depressive Disorder

According to the Diagnostic and Statistical Manual of Mental Disorders fourth edition (DSM-IV), Major Depressive Disorder is characterized by one or more Major Depressive Episodes that cannot otherwise be accounted for by Bipolar Disorder, Substance Abuse Disorder, Schizoaffective Disorder, Schizophrenia, Delusional Disorder, Psychotic Disorder, or a Mood Disorder resulting from a Generalized Medical Condition. Essentially, in order to be diagnosed with Major Depression, the depression symptoms cannot be better explained by something else.

Major Depressive Episode

The DSM-IV states that to have a depressive episode, an individual must have either a depressed mood or the loss of interest in pleasurable activities lasting for at least a two-week duration. Additionally, the person must have at least 4 of the following 7 symptoms during the same two-week period:

  1. Significant weight loss (when not dieting) or weight gain.
  2. Insomnia or hypersomnia nearly every day.
  3. Psychomotor agitation or retardation nearly every day.
  4. Fatigue or loss of energy nearly every day.
  5. Feelings of worthlessness or excessive guilt nearly every day.
  6. Diminished ability to think or concentrate, or indecisiveness, nearly every day.
  7. Recurrent thoughts of death (not fear of dying), recurrent suicidal ideation with or without a plan, or a previous suicide attempt.

Suicide as a Symptom

Major Depression is known to have a high mortality rate; up to 15% of individuals with Major Depressive Disorder will die by suicide. In the United States alone there are over 35,000 completed suicides every year, and a high percentage of them are believed to be by individuals suffering from MDD.

Causes of Major Depression


Major Depressive Disorder is known to be associated with low levels of the neurotransmitter Serotonin. Although researchers have proven that a genetic factor is involved, it is not known if this is the only cause of MDD. Major Depression is a disease; it has distinctive physiological traits and symptoms. Although no one knows if the disease is curable, it is considered to be 100% treatable. Sadly, it is estimated that less than half of the people afflicted with this disorder will ever seek treatment.


The two most common forms of treatment are anti-depressant medications and psychotherapy. Most depression experts agree that a client's chance for remission is greatly enhanced when a combination of these two therapies is used.

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