The causes of depression are related to psychosocial and physiological factors. If negative emotions are experienced in life, or negative life events occur, this may be a trigger for depression. That is, anger, may trigger depression. However, depression often has a long-term personality basis as well as a physiological basis prior to the onset of the disorder. The personality basis is manifested by the patient’s pre-morbid introversion, reluctance to communicate with others, fewer interests, and reluctance to engage in group activities. This includes the patient’s habits of living, mostly alone, and the inability to express negative emotions. The physiological basis of the disease is a reduced concentration of pentraxin in the synaptic gap, and in some severe cases, a reduced concentration of norepinephrine. Therefore, a patient who is introverted and has a neurotransmitter deficit before the disease. Depression can be triggered by anger or other negative life events.