Simply put, when one of the following factors occurs, it changes our brain chemistry in some way. Of course, the factors themselves can vary in intensity; so a job change can vary from moving to a new cube, getting a new boss, being transferred to new department, being transferred to a new city, getting a demotion, getting fired, getting arrested for imbezzlement, etc. So when you say job change, that can mean many different things.
Add to that, the way we react to that change. For some people, getting a new boss is a huge deal, others, its no biggie. It doesnt meant the former person is weaker or inferior than the latter, it just means that the person reacted differently.
So, a job change occurs and our brain chemistry changes somewhat depending upon the type of change and our reaction to it. If multiple things happen our chemistry can change to the point where we are getting low in them which is a common cause of depression.
Let's look at some of these factors:
Genetics and biology.
Like other medical conditions, for example heart disease, cholesterol, and cancer, depression tends to run in families. People can be born with a certain predisposition to depression or have lower levels of chemical neurotransmitters to begin with.
Childhood trauma and other psychological factors.
As we discussed, changes in our psychology (reactions to trauma, personal loss, rejection) can also alter the biochemistry of the brain and nervous system - sometimes permanently. How we adjust to traumas, or how we are taught to adjust, can have a huge impact on the likelihood of develping clinical depression.
Environmental factors.
Poor nutrition, hormonal imbalances, toxins in the environment, brain injuries, stress, substance abuse, and can lead to depressive states. Good nutrition, decreasing stress, healthy lifestyles are keys to minimizing depressive symptoms. Alcohol depresses the nervous system, thus drinking too much, too often can lead to depressive states. Thus, moderation in drinking alcohol is essential.
Prescription medications
Many people do not realize that many common prescription drugs have side effects that can induce depression. These include cardiac drugs and hypertensives, sedatives, steroids, stimulants, antibiotics, antifungal drugs and analgesics.
Sociological factors.
Many changes in modern society, such as the breakdown of traditional communities (people don't stay in one spot for very long any more), the dissolution of extended families (with mobility in the world, often families are spread throughout the country or world), the widening gap between rich and poor, and our increased isolation due to technology (we text/email people instead of calling or visiting), may play a part in the rising rates of depression worldwide.
Spiritual crises.
People can suffer from an existential depression when life loses its meaning and purpose. Any significant transition, especially a change of roles in family or work, can trigger this crisis in meaning. Connection to a "Higher Power"has been shown to increase mood and levels of neurochemicals.
Next, we'll look at symptoms of clinical depression...
