Final answer:
Depression is associated with biological factors such as high norepinephrine levels, abnormal serotonin levels, and a family history of the disorder. These factors influence neurotransmitter imbalance, contributing to the development of depressive symptoms.
Step-by-step explanation:
Biological Factors of Depression
The biological factors for depression include high levels of the neurotransmitter norepinephrine, abnormal levels of serotonin, and family history. Studies suggest that depression may be linked to genetic factors, as a family history of depression can significantly increase one's own risk. Furthermore, an imbalance in neurotransmitters, which are chemical messengers in the brain, has been implicated in depression. Specifically, serotonin, which is involved in mood regulation, can have reduced levels in those with depression. Medications known as antidepressants often aim to normalize serotonin levels. Another neurotransmitter, norepinephrine, is also associated with depression; however, the relationship is complex and not fully understood. The 'classic monoamine hypothesis' suggests that a decrease in both norepinephrine and serotonin transmission contributes to depression. This hypothesis is supported by the fact that many antidepressants increase these neurotransmitters' levels, although the onset of therapeutic effects takes weeks, indicating other mechanisms may be involved.
Biological factors for depression include high norepinephrine, abnormal serotonin, and family history. Depression is thought to be caused by a decrease in norepinephrine and serotonin neurotransmission. Medications called antidepressants help bring serotonin levels back to normal for many people with depression.