Depression can take many forms, and it is attributed by the Mayo Clinic and others to a blend of social, genetic and environmental triggers. However, the biological components of depression are a major factor influencing the severity, extent and type of symptoms experienced by those suffering from depression. By understanding the biological components of depression, it is possible to develop a greater overall understanding of depression.
Neurotransmitters
A critical part of the manifestation of depression is tied to the levels of neurotransmitters in the brain and throughout the body. According to Healthy Place, the two main neurotransmitters linked to depression are serotonin and norepinephrine.
Serotonin is linked to sleeping problems, but it also contributes to mood control elements. When serotonin levels are at less than optimal levels, anxiety and irritability come to the forefront, creating some of the mood swing issues often present in depression.
Norepinephrine regulates arousal and alertness. When it is lacking in the body, the biological deficiency creates the exhibited listlessness and loss of interest in daily activities that are characteristic of depression. Chronic fatigue has also been linked to norepinephrine deficits.
Hormones
Another biological component of depression is a shift in hormonal production cycles. When a depressive state is present, hormone cycles function in different ways, sometimes peaking earlier in the day or not producing the regular amounts, according to InDepression.com.
A prime example of this is found with the hormone cortisol. Cortisol in depressed individuals is produced in lower amounts, and the cycle of production works differently. This prevents depressed individuals from maintaining appropriate responses to stressors in their lives and regulating their adrenal responses.
Another biological element tied to hormones manifests in women. Due to hormonal changes as a result of pregnancy, hormone levels shift dramatically. These shifts can trigger depressive incidents.
Response to Physical Trauma or Psychological Events
According to the Mayo Clinic, depression can also be a biological response to a physically traumatic event or a major psychological experience. Car accidents, workplace accidents, or other major physical events can generate a response stimulus that pushes the body into depression. Emotional loss or trauma, such as a death in the family, divorce, or loss of a close friend can also trigger response systems that push the body into a depressive state.
